Migratory Bird Hunting; Approval of Tungsten-Iron-Copper-Nickel, Iron-Tungsten-Nickel Alloy, and Tungsten-Bronze (Additional Formulation), and Tungsten-Tin-Iron Shot Types as Nontoxic for Hunting Waterfowl and Coots; Availability of Environmental Assessments, 49541-49553 [05-16718]
Download as PDF
<![CDATA[
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
[FR Doc. 05–16813 Filed 8–23–05; 8:45 am]
BILLING CODE 6560–50–P
DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 20
RIN 1018–AU04; 1018–AU 09; 1018–AU13;
1018–AU28
Migratory Bird Hunting; Approval of
Tungsten-Iron-Copper-Nickel, IronTungsten-Nickel Alloy, and TungstenBronze (Additional Formulation), and
Tungsten-Tin-Iron Shot Types as
Nontoxic for Hunting Waterfowl and
Coots; Availability of Environmental
Assessments
AGENCY: Fish and Wildlife Service,
Interior.
ACTION: Proposed rule; notice of
availability.
SUMMARY: The U.S. Fish and Wildlife
Service (we, us, or USFWS) proposes to
approve four shot types or alloys for
hunting waterfowl and coots and to
change the listing of approved nontoxic
shot types in 50 CFR 20.21(j) to reflect
the cumulative approvals of nontoxic
shot types and alloys.
These four shot types or alloys were
submitted to us separately, and we
published advance notices of proposed
rulemakings for these shot types under
RINs 1018–AU04, 1018–AU09, 1018–
AU13, and 1018–AU28, respectively.
We now combine all these actions under
RIN 1018–AU04.
In addition, we propose to approve
alloys of several metals because we have
approved the metals individually at or
near 100% in nontoxic shot.
DATES: Send comments on this proposal
by September 23, 2005.
ADDRESSES: You may submit comments,
identified by RIN 1018–AU04, by any of
the following methods:
• Federal eRulemaking Portal: https://
www.regulations.gov. Follow the
instructions for submitting comments.
• Agency Web Site: https://
migratorybirds.fws.gov. Follow the links
to submit a comment.
• E-mail address for comments:
George_T_Allen@fws.gov. Include ‘‘RIN
1018–AU04’’ in the subject line of the
message. Please submit electronic
comments as text files; do not use file
compression or any special formatting.
• Fax: 703–358–2217.
• Mail: Chief, Division of Migratory
Bird Management, U.S. Fish and
Wildlife Service, 4401 North Fairfax
Drive, Mail Stop MBSP–4107,
Arlington, Virginia 22203–1610.
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
• Hand Delivery: Division of
Migratory Bird Management, U.S. Fish
and Wildlife Service, 4501 North Fairfax
Drive, Room 4091, Arlington, Virginia
22203–1610.
For specific instructions on
submitting or inspecting public
comments, inspecting the complete file
for this rule, or requesting a copy of the
draft environmental assessment, see
Public Comments in SUPPLEMENTARY
INFORMATION.
FOR FURTHER INFORMATION CONTACT: Dr.
George T. Allen, Division of Migratory
Bird Management, 703–358–1714.
SUPPLEMENTARY INFORMATION:
Background
The Migratory Bird Treaty Act of 1918
(Act) (16 U.S.C. 703–711) and the Fish
and Wildlife Improvement Act of 1978
(16 U.S.C. 712) implement migratory
bird treaties between the United States
and Great Britain for Canada (1916,
amended), Mexico (1936, amended),
Japan (1972, amended), and Russia
(then the Soviet Union, 1978). These
treaties protect certain migratory birds
from take, except as permitted under the
Acts. The Acts authorize the Secretary
of the Interior to regulate take of
migratory birds in the United States.
Under this authority, the U.S. Fish and
Wildlife Service controls the hunting of
migratory game birds through
regulations in 50 CFR part 20.
Deposition of toxic shot and release of
toxic shot components in waterfowl
hunting locations are potentially
harmful to many organisms. Research
has shown that ingested spent lead shot
causes significant mortality in migratory
birds. Since the mid-1970s, we have
sought to identify shot types that do not
pose significant toxicity hazards to
migratory birds or other wildlife. We
addressed the issue of lead poisoning in
waterfowl in an Environmental Impact
Statement in 1976, and again in a 1986
supplemental EIS. The 1986 document
provided the scientific justification for a
ban on the use of lead shot and the
subsequent approval of steel shot for
hunting waterfowl and coots that began
that year, with a complete ban of lead
for waterfowl and coot hunting in 1991.
We have continued to consider other
potential candidates for approval as
nontoxic shot. We are obligated to
review applications for approval of
alternative shot types as nontoxic for
hunting waterfowl and coots.
We have received applications for
approval of four shot types as nontoxic
for hunting waterfowl and coots. Those
shot types are:
1. Tungsten-Iron-Copper-Nickel
(TICN) shot, of 40–76 percent tungsten,
PO 00000
Frm 00034
Fmt 4702
Sfmt 4702
49541
10–37 percent iron, 9–16 percent
copper, and 5–7 percent nickel (70 FR
3180, January 21, 2005);
2. Iron-Tungsten-Nickel (ITN) alloys
composed of 20–70 percent tungsten,
10–40 percent nickel, and 10–70 percent
iron (70 FR 22625, May 2, 2005);
3. Tungsten-Bronze (TB) shot made of
60 percent tungsten, 35.1 percent
copper, 3.9 percent tin, and 1 percent
iron (70 FR 22624, May 2, 2005, Note:
This formulation differs from the
Tungsten-Bronze nontoxic shot
formulation approved in 2004.); and
4. Tungsten-Tin-Iron (TTI) shot
composed of 58 percent tungsten, 38
percent tin, and 4 percent iron.
The metals in these shot types have
already been approved in other nontoxic
shot types. In considering approval of
these shot types, we were particularly
concerned about the solubility and
bioavailability of the nickel and copper
in them. In addition, because tungsten,
tin, and iron have already been
approved at very high proportions of
other nontoxic shot types with no
known negative effects of the metals, we
will propose approval of all alloys of
these four metals.
The data provided to us indicate that
the shot types are nontoxic when
ingested by waterfowl and should not
pose a significant danger to migratory
birds, other wildlife, or their habitats.
We conclude that they raise no
particular concerns about deposition in
the environment or about ingestion by
waterfowl or predators.
The process for submission and
evaluation of new shot types for
approval as nontoxic is given at 50 CFR
20.134. The list of shot types approved
as nontoxic for use in hunting migratory
birds is provided in the table at 50 CFR
20.21(j). With this proposed rule, we
also propose to revise the listing of
approved nontoxic shot types in
§ 20.21(j) to include the cumulative
approvals of the shot types considered
in this proposed rule with the other
nontoxic shot types already in the table.
Many hunters believe that some
nontoxic shot types do not compare
favorably to lead and that they may
damage some shotgun barrels, and a
small percentage of hunters have not
complied with nontoxic shot
regulations. Allowing use of additional
nontoxic shot types may encourage
greater hunter compliance and
participation with nontoxic shot
requirements and discourage the use of
lead shot. The use of nontoxic shot for
waterfowl hunting has increased in
recent years (Anderson et al. 2000), but
we believe that compliance will
continue to increase with the
availability and approval of other
E:\FR\FM\24AUP1.SGM
24AUP1
49542
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
nontoxic shot types. Increased use of
nontoxic shot will enhance protection of
migratory waterfowl and their habitats.
More important, however, is that the
Fish and Wildlife Service is obligated to
consider all complete nontoxic shot
submissions.
We also propose to add a column to
the table of approved shot types that
lists the field testing device suitable for
each shot type. The information in this
column is strictly informational, not
regulatory. Because these regulations are
used by both waterfowl hunters and law
enforcement officers, we believe that
information on suitable testing devices
is a useful addition to the table.
Affected Environment
Waterfowl Populations
The taxonomic family Anatidae,
principally subfamily Anatinae (ducks)
and their habitats, comprise the affected
environment. Waterfowl habitats and
populations in North America in 2004
were described by the U.S. Fish and
Wildlife Service (Garrettson et al. 2004).
In the Breeding Population and Habitat
Survey traditional survey area (strata 1–
18, 20–50, and 75–77), the total-duck
population estimate was 32.2 ± 0.6 (± 1
standard error) million birds, 11 percent
below the 2003 estimate of 36.2 ± 0.7
million birds, and 3 percent below the
1955–2003 long-term average. Mallards
(Anas platyrhynchos) were estimated at
7.4 ± 0.3 million, similar to last year’s
estimate of 7.9 ± 0.3 million birds and
to the long-term average. Blue-winged
teal (A. discors) numbered 4.1 ± 0.2
million, 26 percent below last year’s
estimate of 5.5 ± 0.3 million and 10
percent below the long-term average.
Among other duck species, only
northern shovelers (A. clypeata, 2.8 ±
0.2 million) and American wigeon (A.
americana, 2.0 ± 0.1 million) were both
goldeneyes (Bucephala clangula and B.
islandica, 0.4 ± 0.1 million), which were
61 percent and 42 percent below their
1996–2003 averages, respectively, and
ring-necked ducks (Aythya collaris, 0.7
± 0.2 million), which increased by 67
percent relative to the 2003 estimate of
their numbers.
22 percent below their 2003 estimates.
As in 2003, gadwall (A. strepera, 2.6 ±
0.2 million, +56 percent), green-winged
teal (A. crecca, 2.5 ± 0.1 million, +33
percent), and northern shovelers (+32
percent) were above their long-term
averages. Northern pintails (A. acuta,
2.2 ± 0.2 million, ·48 percent), scaup
(Aythya affinis and A. marila, 3.8 ± 0.2
million, ·27 percent), and American
wigeon (·25 percent) were well below
their long-term averages in 2004.
Characterization of the Four Shot Types
TICN Alloys
Spherical Precision, Inc. of Tustin,
CA, submitted Tungsten-Iron-CopperNickel (TICN) shot for approval. The
advance notice of proposed rulemaking
for this group of alloys was published in
the Federal Register on January 21,
2005, under RIN 1018–AU04 (70 FR
3180). This is an array of layered alloys
or metals of 40–76 percent tungsten, 10–
37 percent iron, 9–16 percent copper,
and 5–7 percent nickel. TICN shot has
a density ranging from 10.0 to 14.0
grams per cubic centimeter (g/cm3), is
noncorrosive, and is magnetic.
Spherical Precision estimates that the
volume of TICN shot for use in hunting
migratory birds in the United States will
be approximately 50,000 pounds (lb)
(22,700 kilograms (kg)) during the first
year of sale, and perhaps 100,000 lb
(45,400 kg) per year thereafter.
Habitats
Waterfowl hunting occurs in habitats
used by many taxa of migratory birds, as
well as by aquatic invertebrates,
amphibians and some mammals. Fish
also may be found in many hunting
locations. In 2004, total May ponds in
Prairie Canada, and the north-central
United States combined were estimated
at 3.9 ± 0.2 million, which was 24
percent lower than the figure for 2003
and 19 percent below the long-term
average. Pond numbers in both Canada
(2.5 ± 0.1 million) and the U. S. (1.4 ±
0.1 million) were below 2003 estimates
(·29 percent in Canada, and ·16
percent in the United States), and pond
numbers in Canada were 25 percent
below the long-term average for the
region.
ITN Alloys
Fall Flight Forecasts
The projected mallard fall flight index
was 9.4 ± 0.1 million birds, similar to
the 2003 estimate of 10.3 ± 0.1 million.
The 2004 total duck population estimate
for the eastern survey area (strata 51–56
and 62–69) was 3.9 ± 0.3 million birds.
This estimate was similar to the 2003
estimate of 3.6 ± 0.3 million birds, and
to the 1996–2003 average. Individual
species estimates for this area were
similar to 2003 estimates and to 1996–
2003 averages, with the exception of
American wigeon (0.1 ± 0.1 million) and
ENVIRON-Metal of Sweet Home, OR,
submitted Iron-Tungsten-Nickel (ITN)
alloys, which are cast alloys containing
10–70 percent iron, 20–70 percent
tungsten, and 10–40 percent nickel. The
advance notice of proposed rulemaking
for this group of alloys published in the
Federal Register on May 2, 2005, under
RIN 1018–AU09 (70 FR 22625). The
proposed shot types have densities
ranging from about 8.5 to about 13.5 g/
cm3. The compositions of the alloys are
shown in table 1.
TABLE 1.—COMPOSITION OF ITN SHOT ALLOYS
Iron
Alloy
1
2
3
4
5
6
.......................................
.......................................
.......................................
.......................................
.......................................
.......................................
Density
(g/cm3) 1
Shot weight
(mg) 2
8.8
9.0
9.8
11.3
13.3
13.55
Percent
165.89
169.65
184.73
213.00
250.71
255.42
70
40
44
10
20
10
Tungsten
Weight
(mg)
Weight
(mg)
Percent
116.12
67.86
81.28
21.30
50.14
25.54
Nickel
20
20
33
50
70
70
33.18
67.86
60.96
106.50
175.49
178.79
Percent
10
40
23
40
10
20
Weight
(mg)
16.59
33.93
42.49
85.20
25.07
51.08
Note.—Weights are based on one number 4 shot.
ENVIRON-Metal estimated that the
yearly volume of ITN shot types with
densities between those of steel (7.86 g/
cm3) and lead (11.3 g/cm3) expected for
use in hunting migratory birds in the
VerDate jul<14>2003
15:01 Aug 23, 2005
Jkt 205001
United States is approximately 200,000
lb (113,500 kg) during the first year of
sale. In the second year and beyond,
sales upwards of 500,000 lb (227,000 kg)
per year are anticipated. ITN shot types
PO 00000
Frm 00035
Fmt 4702
Sfmt 4702
with densities greater than that of lead
may ultimately attain sales levels of
1,000,000 lb (454,000 kg) per year.
E:\FR\FM\24AUP1.SGM
24AUP1
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
TB Shot
The Olin Corporation of East Alton,
IL, submitted Tungsten-Bronze (TB)
shot for approval. The advance notice of
proposed rulemaking for this shot type
was published in the Federal Register
on May 2, 2005, under RIN 1018–AU13
(70 FR 22624). This is a sintered
composite with an average composition
of 60 percent tungsten, 35.1 percent
copper, 3.9 percent tin, and 1 percent
iron. The copper and tin make up 39
percent of the shot as a 90:10 ratio,
respectively, in the form of a bronze
alloy. The shot has a density of 12.0 g/
cm3, compared to 11.1–11.3 g/cm3 for
lead, and 7.9 g/cm3 for steel. Olin
estimated that the yearly volume of the
TB shot in hunting migratory birds in
North America will be approximately
300,000 lb (136,200 kg).
TTI Shot
Tungsten-Tin-Iron (TTI) shot,
submitted by Nice Shot, Inc., of Albion,
PA, is a cast alloy composed of 58
percent tungsten, 38 percent tin, and 4
percent iron. This shot type has a
density of 11.0 g/cm3. Nice Shot, Inc.
estimated that approximately 5,000 lb
(2,270 kg) of TTI shot are expected to be
sold for use in hunting migratory birds
in the United States during the first year
of sale. TTI shot contains less than 1
percent lead, and will not be coated.
Each of the four shot types has a
residual lead level of less than 1
percent. To inhibit corrosion, TICN shot
may be coated with tin, and ITN shot
may be surface-coated with thin
petroleum-based films. Neither TB nor
TTI shot will be coated.
Environmental Fate of the Metals in the
Four Shot Types
All of the metals in these shot types
have been approved in other nontoxic
shot types, and the submitters asserted
that the four shot types pose no adverse
toxicological risks to waterfowl or other
forms of terrestrial or aquatic life. Our
particular concern in considering
approval of these shot types is the
solubility and bioavailability of the
nickel and copper in them.
The metals in the four shot types are
insoluble under hot and cold (Weast
1986). Neither manufacturing the shot
nor firing shotshells containing the shot
will alter the metals or change how they
dissolve in the environment. The shot
types are not chemically or physically
altered by firing from a shotgun.
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
Iron is naturally widespread. It
comprises approximately 2 percent of
the composition of soils and sediments
in the United States. The iron in the
shot types is not soluble.
Elemental tungsten and iron are
virtually insoluble in water, and
therefore do not weather and degrade in
the environment. Tungsten is stable in
acids and does not easily form
compounds with other substances.
Preferential uptake by plants in acidic
soil suggests uptake of tungsten when it
has formed compounds with other
substances rather than when it is in its
elemental form (Kabata-Pendias and
Pendias 1984).
Elemental copper can be oxidized by
organic and mineral acids that contain
an oxidizing agent. Elemental copper is
not oxidized in water (Aaseth and
Norseth 1986).
Nickel is common in fresh waters,
though usually at concentrations of less
than 1 part per billion (p/b) in locations
unaffected by human activities. Pure
nickel is not soluble in water, and
resists corrosion at temperatures
between ·20 °C and 30 °C (Chau and
Kulikovsky-Cordeiro 1995). Free nickel
may be part of chemical reactions, such
as sorption, precipitation, and
complexation. ‘‘Under anaerobic
conditions, typical of deep groundwater,
precipitation of nickel sulfide keeps
nickel concentrations low’’ (Eisler
1998). Reactions of nickel with anions
are unlikely. Complexation with organic
agents is poorly understood (U.S.
Environmental Protection Agency [EPA]
1986). Water hardness is the dominant
factor governing nickel effects on biota
(Stokes 1988).
Tin is only very slightly soluble at pH
values from 4 to 11, as found in natural
settings. Tin occurs naturally in soils at
2 to 200 mg/g (parts per thousand or
ppt) with areas of enrichment at
concentrations up to 1,000 mg/g (WHO
1980). In general, however, soil
concentrations in the United States are
between 1 and 5 parts per million (p/m)
(Kabata-Pendias and Pendias 1984).
Possible Environmental Concentrations
for Metals in the Four Shot Types in
Terrestrial Systems
Calculation of the estimated
environmental concentration (EEC) of a
candidate shot in a terrestrial ecosystem
is based on 69,000 shot per hectare (50
CFR 20.134). These calculations assume
PO 00000
Frm 00036
Fmt 4702
Sfmt 4702
49543
that the shot dissolves promptly and
completely after deposition.
TICN Alloys
The maximum EEC for TICN shot for
tungsten in soil is 21.3 p/m. This is
below the EEC for several other
tungsten-based shot types that we have
previously approved. We are not aware
of any problems associated with those
shot types. The U.S. EPA does not have
a biosolids application limit for
tungsten.
For TICN shot, if the shot are
completely dissolved in dry, porous
soil, the maximum EEC for iron is 7.40
p/m. Iron is naturally widespread,
comprising approximately 2 percent of
the composition of soils and sediments
in the United States. The EEC for iron
from TICN shot is much lower than that
level.
For copper in TICN shot, the
maximum EEC in soils is 3.36 p/m. In
comparison, the ceiling concentration
limit for biosolids application for
copper is 4,300 p/m (EPA 2000).
The maximum EEC for nickel in TICN
shot in soils is 1.62 p/m. This
concentration is a small fraction of the
EPA biosolids application limit of 420
p/m (EPA 2000).
If TICN shot is coated with tin, the
EEC for tin in dry soils is 1.31 p/m.
There is no EPA biosolids application
limit for tin, but it occurs naturally in
soils at 2 to 200 p/m, with areas of
enrichment at concentrations up to
1,000 p/m (WHO 1980). In general, soil
concentrations in the United States are
between 1 and 5 p/m; the suggested
maximum concentration in surface soil
tolerated by plants is 50 p/m dry weight
(Kabata-Pendias and Pendias 1984).
ITN Alloys
The terrestrial EECs for the iron and
tungsten from any ITN alloy (table 2) are
below those from approved shot types,
and we do not believe they are a
problem in soils. Though data on iron
concentrations in biosolids are
unavailable, natural soil background
concentrations range from 5,000 to
50,000 p/m. This is equivalent to 32,500
to 325,000 kg per hectare (kg/h). We do
not believe that the worst-case
additional 8.01 kg of iron per hectare
(about 0.025 percent of natural
background concentrations) would have
any effect on plants or animals,
especially since the iron in the shot is
not in a soluble form.
E:\FR\FM\24AUP1.SGM
24AUP1
49544
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
TABLE 2.—EXPECTED TERRESTRIAL ENVIRONMENTAL CONCENTRATIONS OF THE METALS IN ITN ALLOYS
Alloy
(% I/T/N)
1
2
3
4
5
6
(70/20/10)
(40/20/40)
(44/33/23)
(10/50/40)
(20/70/10)
(10/70/20)
Shot weight
(kg)
..............................................
..............................................
..............................................
..............................................
..............................................
..............................................
11.446
11.706
12.746
14.700
17.299
17.624
Data from biosolid studies indicate
that tungsten generally is present at 40
to 180 p/m, about four times the worst
EEC for tungsten from ITN shot.
Therefore, it is unlikely that tungsten
from the shot would exceed
concentrations obtained from biosolid
applications.
The estimated soil concentration (p/m
soil) of nickel for ITN alloy 4 (the
highest in nickel) is a very small
fraction of the 420 p/m maximum
concentration allowed for terrestrial
application of biosolids and is two
orders of magnitude less than the
maximum cumulative loading rate for
nickel of 420 kg/h per year (https://
www.epa.gov/cgi-bin/claritgw). We do
not believe that nickel from ITN shot
would pose an environmental problem
in soils.
TB Shot
Based on the maximum concentration
of each metal in any formulation of TB
shot, the increased concentrations in
soils for the metals are 14.4 p/m for
tungsten, 8.43 p/m for copper, 0.94
p/m for tin, and 0.24 p/m for iron. The
EEC for tungsten is lower than the value
for ITN shot, and considerably lower
than the values for previously approved
shot types. As noted earlier, the ceiling
concentration limit for biosolids
application for copper is 4,300 p/m
(EPA 2000). The EEC for iron from TB
shot is extremely small.
TTI Shot
The EEC for tungsten in TTI shot in
soil (the increase in soil concentration)
is 12.77 mg/kg or p/m. This is below the
EEC for several other tungsten-based
shot types that we have previously
approved. We are not aware of any
problems associated with those shot
types. The EPA does not have a
biosolids application limit for tungsten.
Data from biosolid studies indicate that
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
Deposition (kg)
Iron
Tungsten
8.01
4.68
5.61
1.47
3.46
1.76
Terrestrial EEC (p/m)
Nickel
2.29
2.34
4.21
7.35
12.11
12.34
tungsten generally is present at 40 to
180 p/m, about four times the worst EEC
for tungsten from ITN shot. Therefore, it
is unlikely that tungsten from the shot
would exceed concentrations obtained
from biosolid applications.
The EEC for tin in dry soils is 8.37
p/m. In general, soil concentrations in
the United States are between 1 and 5
p/m; the suggested maximum
concentration in surface soil tolerated
by plants is 50 p/m dry weight (KabataPendias and Pendias 1984), about six
times the worst-case concentration to be
expected from TTI shot.
If the shot are completely dissolved in
dry, porous soil, the maximum EEC for
iron is 0.88 p/m. Iron is naturally
widespread, comprising approximately
2 percent of the composition of soils
and sediments in the United States. The
EEC for iron from TTI shot is much
lower than that level.
Though data on iron concentrations in
biosolids are unavailable, natural soil
background concentrations range from
5,000 to 50,000 p/m. This is equivalent
to 32,500 to 325,000 kg per hectare. We
do not believe that the extremely small
addition of the insoluble iron from TTI
shot would have any effect on plants or
animals, especially because the iron in
the shot is not in a soluble form.
Possible Environmental Concentrations
for Metals in the Four Shot Types in
Aquatic Systems
The EEC for water assumes that
69,000 number 4 shot are completely
dissolved in 1 hectare of water 1 foot (ft)
(30.48 cm) deep. The submitter then
calculates the concentration of each
metal in the shot if the shot pellets
dissolve completely. For our analyses,
we assume complete dissolution of the
shot type containing the highest
proportion of each metal in the range of
alloys submitted.
PO 00000
Frm 00037
Fmt 4702
Sfmt 4702
Iron
1.15
4.68
2.93
5.88
1.73
3.52
12.33
7.20
8.63
2.26
5.32
2.71
Tungsten
3.52
3.60
6.47
11.31
18.63
18.98
Nickel
1.76
7.20
4.51
9.05
2.66
5.42
TICN Alloys
For TICN shot, the EEC for tungsten
is 4.541 milligrams per liter (mg/l). The
EPA has set no acute or chronic criteria
for tungsten in aquatic systems.
The EEC for iron from TICN shot in
water is 1.579 mg/l. The chronic water
quality criterion for iron in fresh water
is 1 mg/l (EPA 1986). EPA has no
criterion for salt water.
For copper, the aquatic EEC is 0.717
mg/l. This value is above both the acute
and chronic criteria for freshwater and
saltwater. This issue is discussed in the
‘‘In Vitro Solubility Evaluation of TICN
Shot’’ section.
The aquatic EEC for nickel from TICN
shot is 0.346 mg/l. The EPA (1986) acute
criterion for nickel in fresh water is
1,400 micrograms per liter (µg/l); the
chronic criterion is 160 µg/l. The acute
and chronic criteria for salt water are 75
and 8.3 µg/l, respectively. Based on the
EEC, the maximum release of nickel
from TICN shot would be well below
the fresh water acute criterion for
protection of aquatic life.
For the tin in TICN shot, the aquatic
EEC is 0.280 mg/l. The lowest published
standard for tin in water is the 4 mg/l
water quality standard for the state of
Minnesota. Even in the worst case, the
tin concentration from dissolved TICN
shot would be well below this standard.
ITN Alloys
The aquatic EECs for the metals in
ITN shot are shown in table 3. The EEC
for nickel exceeds aquatic water quality
criteria (table 4). However, corrosion
studies demonstrated that corrosion
rates for all types of ITN shot are
relatively low in both fresh water and
seawater. This corrosion is discussed
under ‘‘In Vitro Solubility Evaluation of
ITN Shot.’’
E:\FR\FM\24AUP1.SGM
24AUP1
49545
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
TABLE 3.—EXPECTED AQUATIC ENVIRONMENTAL CONCENTRATIONS OF THE METALS IN ITN ALLOYS
Alloy
(% I/T/N)
1
2
3
4
5
6
(70/20/10)
(40/20/40)
(44/33/23)
(10/50/40)
(20/70/10)
(10/70/20)
Shot weight
(kg)
..............................................
..............................................
..............................................
..............................................
..............................................
..............................................
11.446
11.706
12.746
14.700
17.299
17.624
Deposition (kg)
Iron
Tungsten
8.01
4.68
5.61
1.47
3.46
1.76
Aquatic EEC (p/m)
Nickel
2.29
2.34
4.21
7.35
12.11
12.34
Iron
1.15
4.68
2.93
5.88
1.73
3.52
Tungsten
2,629
1,536
1,840
482
1,135
578
Nickel
751
768
1,380
2,411
3,973
4,048
376
1,536
962
1,929
568
1,156
TABLE 4.—AQUATIC LIFE CRITERIA AND WORST-CASE CONCENTRATIONS OF METALS IN ITN SHOT
Metal
Acute water quality criterion for aquatic
life
(µg/l)
Chronic water quality criterion for
aquatic life
(µg/l)
Iron .........................................................
Tungsten ................................................
Nickel (fresh water) ...............................
Nickel (salt water) ..................................
No Criterion ..........................................
No Criterion ..........................................
1,400 ....................................................
75 .........................................................
1,000 ....................................................
No Criterion ..........................................
160 .......................................................
8.3 ........................................................
TB Shot
copper is considerably above the criteria
for protection of fresh water and salt
water life. However, a solubility study
for this shot type demonstrated that
The aquatic EECs for metals in TB
shot are shown in table 5. The EEC for
Maximum EEC from
ITN alloys
2,629
4,048
1,929
1,929
(Alloy
(Alloy
(Alloy
(Alloy
1).
6).
4).
4).
corrosion of TB shot is low. This is
discussed under ‘‘In Vitro Solubility
Evaluation of TB Shot.’’
TABLE 5.—AQUATIC LIFE CRITERIA AND CONCENTRATIONS OF METALS IN TB SHOT
Metal
Acute water quality criterion for aquatic
life
(µg/l)
Chronic water quality criterion for aquatic
life
(µg/l)
Maximum EEC
from TB shot
Tungsten ..................................................
Copper (Fresh Water) .............................
Copper (Salt Water) ................................
Tin ............................................................
Iron ...........................................................
No Criterion .............................................
13.0 ..........................................................
4.8 ............................................................
4,0001 1 ...................................................
No Criterion .............................................
No Criterion .............................................
9.0 ............................................................
3.1 ............................................................
No Criterion .............................................
1,000 ........................................................
3,073
1,797
1,797
199.7
51.2
1 Minnesota
water quality standard, no federal standard for comparison.
TTI Shot
The EEC for tungsten is 2.72
milligrams per liter (mg/1). The EPA has
set no acute or chronic criteria for
tungsten in aquatic systems.
The aquatic EEC for tin is 1.78 mg/1.
The lowest published standard for tin in
water is the 4 mg/1 water quality
standard for the state of Minnesota. Tin
concentration from dissolved TTI shot
would be well below this standard.
The EEC for iron from TTI shot in
water is 0.19 mg/1. The chronic water
quality criterion for iron in fresh water
is 1 mg/1 (EPA 1986). EPA has no
criterion for salt water.
In Vitro Solubility Evaluation of TICN
Shot
When nontoxic shot is ingested by
waterfowl, both physical breakup of the
shot, and dissolution of the metals that
comprise the shot, may occur in the
highly acidic environment of the
gizzard. In addition to the standard Tier
1 application information, Spherical
VerDate jul<14>2003
15:01 Aug 23, 2005
Jkt 205001
Precision provided the results of an in
vitro gizzard simulation test conducted
to quantify the release of metals in
solution under the prevailing pH
conditions of the avian gizzard. The
metal concentrations released during
the simulation test were, in turn,
compared to known levels of metals that
cause toxicity in waterfowl. The
evaluation followed the methodology of
Kimball and Munir (1971) as closely as
possible. The average amount of copper
and nickel released from eight TICN
shot per day are 1.87 mg and 1.77 mg,
respectively.
The maximum tolerable level of
dietary copper during the long-term
growth of chickens (Gallus domesticus)
and turkeys (Meleagris species) has been
reported to be 300 p/b (Committee on
Mineral Toxicity in Animals (CMTA)
1980). At the maximum tolerable level
for chronic exposure of 300 ppb for
poultry, a 1.8 kg chicken consuming 100
g of food per day (Morck and Austic
1981) would consume 30 mg copper per
day (16.7 mg of copper per kg of body
PO 00000
Frm 00038
Fmt 4702
Sfmt 4702
weight per day). The average amount of
copper released from eight TICN shot is
1.87 mg per day, which is well below
concentrations that cause copper
toxicosis in waterfowl. A bird would
have to ingest 129 TICN shot to exceed
the maximum tolerable level.
No reproductive or other effects were
observed in mallards that consumed the
equivalent of 102 mg of nickel as nickel
sulfate each day for 90 days (Eastin and
O’Shea 1981). Therefore, the average
amount of nickel released from eight
TICN shot/day of 1.77 mg will pose no
risk of adverse effects to waterfowl.
Additionally, metallic nickel likely has
a lower absorption from the
gastrointestinal tract than does the
nickel sulfate used in the mallard
reproduction study, further decreasing
the absorbed dose of TICN shot
compared to the published toxicity
study described above.
We concluded that TICN shot is very
resistant to degradation, and that it
poses no risk to waterfowl if ingested in
the field. The slow breakdown rate of
E:\FR\FM\24AUP1.SGM
24AUP1
49546
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
1.53 mg per shot per day only permits
the release of 0.233 mg of copper and
0.221 mg of nickel per shot per day,
both of which are concentrations that
are orders of magnitude below toxic
levels of concern for copper and nickel
in waterfowl.
In Vitro Solubility Evaluation of ITN
Shot
Fresh water, seawater, and an
‘‘artificial gizzard’’ environment
(Kimball and Munir, 1971) were
evaluated to determine their corrosion
rates on each of the six alloys, plus steel
as a standard. The ‘‘artificial gizzard’’
test, although developed for lead alloy
evaluation, proved to reliably simulate
the mallard gizzard for both steel and
ITN alloys and constitutes a very
conservative approach for evaluation of
nontoxic shot. This test resulted in
corrosion/erosion rates up to twice
those measured in steel and TungstenNickel-Iron mallard in-vivo studies
(January 4, 2001, 66 FR 737).
The ITN alloys with relatively low
concentrations of tungsten and nickel
corrode in a manner similar to that of
steels. Corrosion rates of such steels are
roughly linear over a wide range of
exposure time. This corrosion is in
contrast with that of alloys such as
stainless steel, tungsten-nickel iron, or
‘‘high-alloy’’ varieties of ITN, which
readily form passivating oxide layers
that impede further corrosion.
Assuming that the short-term rate of
shot weight loss would continue for one
month in a static aqueous environment
(a conservative assumption, because
natural fresh water and seawater
environments are dynamic, and because
corrosion products forming on metal
surfaces tend to progressively retard
corrosion rates), the actual EECs are
presented in table 6. These data show
that the nickel concentration from ITN
shot actually will be well below both
the acute and chronic criteria for nickel
in aquatic settings.
TABLE 6.—ENVIRONMENTAL CONCENTRATIONS OF METALS IN ITN SHOT BASED ON SOLUBILITY TESTING
Fresh Water EEC (µg/l)
Alloy
(% I/T/N)
1
2
3
4
5
6
(70/20/10)
(40/20/40)
(44/33/23)
(10/50/40)
(20/70/10)
(10/70/20)
Iron
..............................................................................................
..............................................................................................
..............................................................................................
..............................................................................................
..............................................................................................
..............................................................................................
ENVIRON-Metal also provided the
results of an in-vitro gizzard simulation
test conducted to quantify the release of
Tungsten
27.16
1.95
12.61
1.45
6.79
0
Nickel
7.76
0.97
9.69
7.27
23.77
0
metals in solution under the prevailing
pH conditions of the avian gizzard (table
7). These data also demonstrate that the
Salt Water EEC (µg/l)
Iron
3.87
1.95
6.70
5.82
3.40
0
Tungsten
3.36
0
10.66
0
2.72
0
Nickel
0.97
0
7.99
0
20.37
0
0.23
0
2.60
0
2.90
0
hazards from these alloys to wildlife
would be very minimal.
TABLE 7.—METAL LOSS FROM ITN ALLOYS IN A SIMULATED GIZZARD OVER A 14-DAY PERIOD.
Initial weight
of 10
number 4
shot
(g)
Alloy
(% I/T/N)
1
2
3
4
5
6
(70/20/10)
(40/20/40)
(44/33/23)
(10/50/40)
(20/70/10)
(10/70/20)
.............................................................................................
.............................................................................................
.............................................................................................
.............................................................................................
.............................................................................................
.............................................................................................
In Vitro Solubility Evaluation of TB
Shot
The EEC for copper EEC was over 138
times the freshwater acute criterion of
13 g/l, and 200 times the freshwater
chronic criterion of 9.0 g/l. However,
Olin noted that the very conservative
assumptions used to calculate the
copper EEC are only an indication of the
likely effect of deposition of TB shot in
an aquatic setting. Therefore, as an
addendum to the application for TB
shot, Olin had an in-vitro dissolution
test in water conducted. The test was
conducted to quantify the release of
metals from TB shot at pH values of 5.6,
6.6, and 7.6 in synthetic buffered
waters. The highest EEC for copper from
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
1.994
2.687
2.766
3.479
3.462
3.418
Weight Loss (mg)
Iron
179.90
64.00
72.60
13.10
18.80
19.40
the dissolution evaluations was 0.15
µg/l at pH 5.6. The hardness-adjusted
chronic water quality criterion for
copper was 9.7 µg/l, approximately 65
times the worst-case EEC. Therefore,
detrimental effects in aquatic systems
from dissolution of TB shot would be
highly unlikely.
Olin provided the results of an invitro gizzard simulation test conducted
to quantify the release of metals in
solution under the prevailing pH
conditions of the avian gizzard. The
simulation test demonstrated that a
number 4 TB shot would release about
0.67 mg of the alloy per day. This, in
turn, would mean release of
approximately 0.24 mg of copper per
day.
PO 00000
Frm 00039
Fmt 4702
Sfmt 4702
Tungsten
51.40
32.00
54.45
65.50
65.80
135.80
Nickel
25.70
64.00
37.95
52.40
9.40
38.8
Percent
weight loss
12.9
5.9
5.9
3.7
2.7
5.7
Olin pointed out that the theoretical
availability of copper from this in-vitro
gizzard simulation test should be
considered maximal when compared to
the Irby et al. (1967) study results or the
CMTA (1980) guideline. Unlike the invivo gizzard, which resembles an open
corrosion system in which the products
of the corrosion process are constantly
being eliminated (Kimball and Munir
1971), the test design for this in-vitro
gizzard simulation was a closed
corrosion system. Therefore, fine pieces
of shot that would be released, and
normally discarded from the gizzard,
remained in the dissolution medium
and potentially yielded more copper.
Additionally, the analytical samples
were analyzed for total metals with no
E:\FR\FM\24AUP1.SGM
24AUP1
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
filtration or centrifugation prior to
analysis. As a result, the fine pieces of
shot that were not fully dissolved and
would normally be excreted were
included in the total copper
concentrations reported.
Summary: Solubility Evaluations
We have previously approved as
nontoxic other shot types that contain
tungsten, iron, and tin. Previous
assessments of nontoxic shot types
indicated that the potential release of
iron, tungsten, or tin from TICN, ITN, or
TB shot should not harm aquatic or
terrestrial systems and we believe the
small amount of tin in TB shot is not
likely to harm waterfowl. The solubility
testing further indicates that the release
of nickel from ITN shot and copper from
TICN or TB shot is not sufficient to
present a hazard to aquatic systems or
to biota. We propose to approve the four
shot types as nontoxic. Our approval is
based on the toxicological report, acute
toxicity studies, reproductive/chronic
toxicity studies, and other published
research. The available information
indicates that the four shot types are
nontoxic when ingested by waterfowl
and that they pose no significant danger
to migratory birds, other wildlife, or
their habitats.
Impacts of Approval of the Four Shot
Types
Effects of the Metals
Iron
Iron is an essential nutrient. Iron
toxicosis in mammals is primarily a
phenomenon of overdosing of livestock.
Maximum recommended dietary levels
of iron range from 500 p/m for sheep to
3000 p/m for pigs (National Research
Council [NRC] 1980). The amount of
iron in any of the four shot types would
not pose a hazard to mammals.
Chickens require at least 55 p/m iron
in the diet (Morck and Austic 1981).
There were no ill effects on chickens fed
1,600 p/m iron in an adequate diet
(McGhee et al. 1965), and chicks
tolerated 1,600 p/m iron in the diets that
included adequate copper, although
decreased weight gains and increased
mortality were observed in copperdeficient diets (McGhee et al. 1965). At
the maximum tolerable level for chronic
exposure of 1,000 p/m for poultry (NRC
1980), a 1.8 kg chicken consuming 100
grams of food per day (Morck and
Austic 1981) would consume 100 mg
iron per day (56 mg per kg of body
weight per day).
Deobald and Elvehjem (1935) reported
that 4,500 p/m iron in the diet produced
rickets in chicks. Adverse effects were
not observed when turkey poults were
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
fed diets amended with 440 p/m iron
(Woerpel and Balloun 1964).
Turkey poults fed 440 p/m in the diet
suffered no adverse effects. The tests, in
which eight number 4 tungsten-iron
shot were administered to each mallard
in a toxicity study indicated that the 45
percent iron content of the shot had no
adverse effects on the test animals
(Kelly et al. 1998).
We are not aware of acute toxicity
data for iron in waterfowl. Zinc-coated
iron shot appeared to have little or no
effect on ducks dosed with eight
number 6 shot; mortality and weight
loss for treated ducks were comparable
to those for control animals (Irby et al.
1967).
Game-farm mallards administered
eight number 4 pellets of tungsten-iron
shot, indicated no adverse effects from
either the tungsten or the iron (Kelly et
al. 1998). This shot formulation has a
much greater iron content (45 percent)
than do the shot types considered here.
Tungsten
Tungsten salts are toxic to mammals.
Lifetime exposure to 5 p/m tungsten as
sodium tungstate in drinking water
produced no discernible adverse effects
in rats (Rattus species) (Schroeder and
Mitchener 1975). However, with 100 p/
m tungsten as sodium tungstate in
drinking water, rats had decreased
enzyme activity after 21 days (Cohen et
al. 1973).
Tungsten may be substituted for
molybdenum in enzymes in mammals.
Ingested tungsten salts reduce growth,
and can cause diarrhea, coma, and death
in mammals (e.g. Bursian et al. 1996,
Cohen et al. 1973, Karantassis 1924,
Kinard and Van de Erve 1941, National
Research Council 1980, Pham-HuuChanh 1965), but elemental tungsten is
virtually insoluble and therefore
essentially nontoxic. Tungsten powder
added to the food of young rats at 2, 5,
and 10 percent by mass for 70 days did
not affect health or growth (Sax and
Lewis 1989). A dietary concentration of
94 p/m did not reduce weight gain in
growing rats (Wei et al. 1987). Exposure
to pure tungsten through oral,
inhalation, or dermal pathways is not
reported to cause any health effects
(Sittig 1991).
Acute tungsten toxicosis results in
death from respiratory paralysis, often
preceded by diarrhea and coma. Chronic
intoxication is most evident in reduced
growth rates. However, the most
sensitive sign is reduced xanthine
oxidase activity. Xanthine oxidase is an
enzyme that is dependent upon
molybdenum for proper functioning. It
is thought that tungsten readily
substitutes for molybdenum, with
PO 00000
Frm 00040
Fmt 4702
Sfmt 4702
49547
subsequent reduction in enzyme
activity; supplemental dietary
molybdenum will reverse the
symptoms. The National Research
Council Committee on Animal Nutrition
recommends a maximum tolerable dose
of 20 p/m tungsten in the diet for
effective rearing of livestock (NRC
1980).
The LD50 of tungsten as sodium
tungstate (Na2WO4) administered by
intraperitoneal injection is 112 p/b body
weight in male rats and 79 p/b body
weight in mice (Mus species) (PhamHuu-Chanh 1965). This would classify
tungsten as ‘‘very toxic’’ when
administered intraperitoneally as a
soluble salt. Kinard and Van de Erve
(1941) showed that Na2WO4 is the most
toxic tungsten salt, when compared
with tungsten oxide and ammonium
paratungstate.
Tungsten administered in the diet had
no effects on rats until reaching 150 p/
m diet when carcinoma incidence was
increased in female Sprague-Dawley rats
(Wei et al. 1987). Higgins et al. (1956a,
b) noted that dietary concentrations of
45 or 94 p/m tungsten produced no
adverse effects on weight gain in
growing rats. Other studies with rats
indicate that dietary exposure to 5,000
p/m tungsten oxide (WO3) or Na2WO4
results in 90 percent and 80 percent
mortality, respectively, by the 70th day
of exposure (NRC 1980). However,
lifetime exposure of rats to 5 p/m
tungsten as Na2WO4 in drinking water
resulted in no observable adverse effects
(Schroeder and Michener 1975). At 100
p/m tungsten as Na2WO4 in drinking
water, rats had decreased enzyme
activity after 21 days of exposure
(Cohen et al. 1973).
Goats (Capra hircus) appear to be less
tolerant of dietary tungsten. A 5-month
exposure to 22.5 p/m dietary tungsten as
Na2WO4 resulted in depressed liver
xanthine oxidase activity in growing
kids. Milk production in goats and cows
(Bos species) was unaffected by a single
oral exposure to 25.0 p/b body weight
of Na2WO4 (Owen and Proudfoot 1968).
Anke and Groppel (1985) established
that goats require at least 0.06 p/m
tungsten in their diets for optimal
reproduction.
Chickens given a complete diet
showed no adverse effects of 250 p/m
sodium tungstate administered for 10
days in the diet. However, 500 p/m in
the diet reduced xanthine oxidase
activity and reduced growth of day-old
chicks (Teekell and Watts 1959). Adult
hens had reduced egg production and
egg weight on a diet containing 1,000
p/m tungsten (Nell et al. 1981).
Ecological Planning and Toxicology
(1999) concluded that the No Observed
E:\FR\FM\24AUP1.SGM
24AUP1
49548
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
Adverse Effect Level for tungsten for
chickens should be 250 p/m in the diet;
the Lowest Observed Adverse Effect
Level should be 500 p/m. Kelly et al.
(1998) demonstrated no adverse effects
on mallards dosed with tungsten-iron or
tungsten-polymer shot according to
nontoxic shot test protocols.
Breeder hen exposure to 250 p/m
tungsten as sodium tungstate for 10 days
had no adverse effects, but increasing
the diet to 500 p/m tungsten for an
additional 20 days resulted in decreased
xanthine oxidase activity (Teekell and
Watts 1959). Similarly, day-old chicks
on a 500 p/m tungsten diet with
adequate molybdenum showed reduced
rate of gain (Selle 1942).
Nell et al. (1981) fed laying hens diets
containing 1,000 p/m tungsten
(unspecified salt) for five months;
control diets contained 0.4 p/m
tungsten. Hens were artificially
inseminated and eggs were collected
and set weekly. Three of 40 hens on the
high-tungsten diet died, and the
remaining 37 had reduced egg
production and egg weight. Egg fertility
and hatchability were not affected. Liver
tungsten was significantly elevated in
treated birds, although there was no
effect on body weight.
Day-old white leghorn chickens
placed on a molybdenum-deficient diet
for 35 days showed a decreased rate of
growth and increased mortality at 45
p/m tungsten as sodium tungstate
(Higgins et al. 1956a, b). However, this
is not an accurate reflection of tungsten
toxicity because low molybdenum
levels potentiate the effects of tungsten
(NRC 1980).
Ecological Planning and Toxicology
(1999) concluded that the No Observed
Adverse Effect Level (NOAEL) for
tungsten for chickens should be 250
p/m in the diet; the Lowest Observed
Adverse Effect Level should be 500
p/m. An adult chicken fed a diet of
1,000 p/m tungsten for 150 days would
ingest about 100 mg of tungsten per day,
or a total of 15 grams. In the USFWS
guidelines for a reproduction study for
shot, mallards would receive eight
number 4 shot on four dosing periods.
A total of 32 TICN shot during the
course of the study, each containing
0.2006 grams of tungsten, would result
in a total exposure of 6.42 grams of
tungsten, if the tungsten in the shot is
totally dissolved. This estimated
exposure of 6.42 grams of tungsten
during a TICN shot mallard
reproductive study is about 43 percent
of the 15 grams demonstrated to cause
reproductive effects in chickens.
The effects of ingestion of tungsten by
mallards as elemental metal in a shot
pellet were studied by Ringelman et al.
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
(1993). Birds were given pellets of 39
percent tungsten, 44.5 percent bismuth,
and 16.5 percent tin by weight, per bird.
No evidence of toxicity or other
histological changes were reported.
Tungsten was not detected in liver or
kidney tissue.
Dosing mallards with eight number 4
Iron-Tungsten shot (with 55 percent
tungsten) also produced no tungsten
toxicity in the ducks (Kelly et al. 1998).
In that study, birds received eight
number 4 pellets by oral gavage and
were observed for changes in serum
enzymes, organ weights, histology of
tissues and accumulation of metals in
bone. Tungsten was detected in femur,
liver, and kidneys of dosed ducks, but
no other significant changes were
measured. Iron-Tungsten shot eroded by
55 percent and Tungsten-Polymer shot
eroded by 80 percent over the course of
the study; however, tissue
concentrations were lower in the
Tungsten-Polymer birds than in the
Iron-Tungsten group. The shot were 55
percent tungsten for the Iron-Tungsten
formulation and 95.5 percent tungsten
for the polymerized shot. The amount of
tungsten in TICN shot (40–76 percent) is
similar to that in the Iron-Tungsten shot
(55 percent). Tungsten-Nickel-Iron shot
in the study by Ecotoxicology &
Biosystems Associates, Inc. (2000),
conducted with a proportion of tungsten
similar to that in TICN shot, was not
toxic.
Kraabel et al. (1996) surgically
embedded tungsten-bismuth-tin shot in
the pectoralis muscles of ducks to
simulate wounding by gunfire and to
test for toxic effects of the shot. The shot
produced no toxic effects nor induced
adverse systemic effects during the 8week study.
Copper
Copper is a dietary essential for all
living organisms. In most mammals,
ingestion of one TICN shot pellet would
result in release of 8 to 25 mg of copper,
not all of which would be absorbed. In
humans, ingestion of a pellet could
mobilize approximately 8 mg of copper.
These low levels of copper would not
pose any risk to mammals.
Copper requirements in birds may
vary depending on intake and storage of
other minerals (Underwood 1971). The
maximum tolerable level of dietary
copper during the long-term growth of
chickens and turkeys is 300 p/m (CMTA
1980). Eight-day-old ducklings were fed
a diet supplemented with 100 p/m
copper as copper sulfate for eight weeks.
They showed greater growth than
controls, but some thinning of the caecal
walls (King 1975). Studying day-old
chicks, Poupoulis and Jensen (1976)
PO 00000
Frm 00041
Fmt 4702
Sfmt 4702
reported that no gizzard lining erosion
could be detected in chicks fed 125
p/m of copper for four weeks, but they
detected slight gizzard erosion in chicks
fed 250 p/m copper. The authors found
that it required 500 to 1,000 p/m of
copper to depress growth and weight
gain of chicks. Jensen et al. (1991) found
that 169 p/m copper in the diet
produced maximal weight gain in
chickens.
Stevenson and Jackson (1979) studied
the influence of dietary copper addition
on the body mass and reproduction of
mature domestic chickens. Hens fed on
a diet containing 250 p/m copper for 48
days showed a similar rate of food
intake as control hens that had no
copper in their diet. Additionally, the
mean number of eggs laid daily did not
differ between hens fed 250 p/m copper
and the controls. After 4 months of
being fed at dietary copper levels in
excess of 500 p/m, negative effects on
the daily food intake, body mass loss,
and egg-laying rates were observed.
At the 300 p/m level for chronic
exposure for poultry, a 1.8 kg chicken
consuming 100 g of food per day (Morck
and Austic 1981) would consume 30 mg
of copper per day (16.7 mg of copper per
kg of body weight/day). One number 4
TICN shot contains a maximum of 31.7
mg of copper. However, at the 0.233 mg
of copper per shot per day release rate
from the solubility testing, a bird would
have to ingest at least 128 TICN shot to
exceed the maximum tolerable level.
Thus, the copper release from the TICN
shot appears to be well below the level
that could cause copper toxicosis in
waterfowl. The average amount of
copper released from 8 TB nontoxic shot
per day is 7.87 mg, so a bird would have
to ingest over 30 shot to exceed the
maximum tolerable level.
Day-old poults fed diets containing
500 p/m ration for 24 weeks showed
reduced growth and increased gizzard
histopathology (Kashani et al. 1986).
Growing domestic turkeys showed no
long-term effects when fed 300 p/m
copper in the daily diet, but 800 p/m of
copper in the diet for 3 weeks inhibited
growth with no adverse effects on
survival (Supplee 1964). No effect of
feeding 400 p/m of copper as copper
sulfate to turkey poults in the daily diet
for 21 weeks was reported, and it was
concluded that poults could tolerate 676
p/m of copper without deleterious
effects. Growth was reduced in poults
fed 800 p/m and 910 p/m of copper over
the same time (Vohra and Kratzer 1968).
Their conclusion was supported by
another study that found that copper in
the diet of domestic turkeys had to rise
to 500 to 750 p/m level before signs of
slight toxicity appeared, assuming that
E:\FR\FM\24AUP1.SGM
24AUP1
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
adequate methionine also was present
(Christmas and Harms 1979).
Henderson and Winterfield (1975)
reported acute copper toxicity in 3week-old Canada geese (Branta
canadensis) that had ingested water
contaminated with copper sulfate. The
authors calculated the copper intake to
be about 600 mg copper sulfate/kg body
weight, or 239 mg copper/kg. The
amount of copper released from eight
number 4 shot would be 42.26 mg,
which is much less that the 239 p/b
toxic level.
Irby et al. (1967) dosed 24 Mallard
ducks with 8 number 6 pure copper shot
to observe if they were toxic over a 60day exposure period. They calculated
that the total mass of copper in the
gizzard was 0.6 gram, and observed that
none of the ducks died from copper
toxicosis after 60 days. TB shot is 35.1
percent copper by weight, so eight shot
would contain 0.64 grams of copper.
International Nontoxic Composites,
Inc. (2003) reported that pure copper
control shot breaks down at the rate of
18.42 mg copper per gram of shot per
day, or 11.05 mg copper per day for 0.6
grams of copper shot, under in vitro
gizzard simulation test conditions.
However, TB shot releases only 4.35 mg
copper per gram of shot per day or 7.87
mg of copper per day for 1.81 grams of
shot under the same test conditions.
This indicates that TB shot should not
be a hazard for wildlife that consume it.
The EPA (2002) provided both acute
and chronic freshwater quality criteria
for copper, which are functions of water
hardness. The freshwater acute criterion
for a water body with hardness of 100
mg/l, for example, is 13 µg/l, and the
chronic criterion is 9.0 µg copper per
liter. The EPA acute and chronic
saltwater quality criteria are not affected
by hardness, and are 4.8 and 3.1 µg/l.
Nickel
Deficiencies have been reported in
diets ranging from 2 to 40 billion p/b
nickel (NRC 1980). The dietary
requirement for nickel has been set at 50
to 80 p/b for the rat and chick (Nielsen
and Sandstead 1974). Humans consume
up to 900 µg per day as a normal dietary
intake (Nieboer et al. 1988). Though it
is necessary for some enzymes, nickel
competes with zinc, calcium, and
magnesium for binding sites on most of
the metal-dependent enzymes, resulting
in various levels of inactivation,
although it is essential for functioning of
some enzymes, particularly urease
(Andrews et al. 1988, Nieboer et al.
1988). Water-soluble nickel salts are
poorly absorbed from the
gastrointestinal tract, averaging only 3
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
percent to 6 percent assimilation
efficiency in rats (Nieboer et al. 1988).
Rats fed nickel carbonate
concentrations up to 1,000 p/m for 3 to
4 months did not show treatmentrelated effects, nor was body weight of
pups affected (Phatak and Patwardhan
1950). Elevated nickel concentrations in
pups were observed in the 500 and
1,000 p/m treatment groups. Young rats
were fed nickel catalyst (finely divided
nickel suspended in vegetable oil and
supported on kieselguhr) at 250 p/m for
16 months with no effects (Phatak and
Patwardhan 1952).
Rats fed 1,000 p/m nickel sulfate for
2 years exhibited mild effects, such as
reduced body weight and liver weight,
but increased heart weight (Ambrose et
al. 1976). Also, there was an increase in
the number of stillborn pups and a
decrease in weanling weights through
three generations. Nickel chloride was
most toxic to rats. Young rats decreased
food consumption and lost body weight
within 13 days in diets containing 1,000
p/m nickel as nickel chloride (Schnegg
and Kirchgessner 1976).
Calves showed weight loss and
decreased feed intake, organ size, and
nitrogen retention when fed 1,000 p/m
nickel and nickel carbonate for 8 weeks
(O’Dell et al. 1970a, 1971). Calves fed
250 p/m nickel did not show effects.
Lactating dairy cows were not affected
by 50 or 250 p/m dietary nickel
(Archibald 1949, O’Dell et al. 1970b).
Soluble nickel salts are very toxic to
mammals, with an oral LD50 of 136 p/
b in mice, and 350 p/b in rats (Fairchild
et al. 1977). Nickel catalyst (finely
divided nickel in vegetable oil) fed to
young rats at 250 p/m for 16 months,
however, produced no detrimental
effects (Phatak and Patwardhan 1952).
Water-soluble nickel salts are poorly
absorbed if ingested by rats (Nieboer et
al. 1988). Nickel carbonate caused no
treatment effects in rats fed 1,000 p/m
for 3 to 4 months (Phatak and
Patwardhan 1952). Rats fed 1,000 p/m
nickel sulfate for 2 years showed
reduced body and liver weights, an
increase in the number of stillborn
pups, and decrease in weanling weights
through three generations (Ambrose et
al. 1976). Nickel chloride was even
more toxic; 1,000 p/m fed to young rats
caused weight loss in 13 days (Schnegg
and Kirchgestiner 1976).
In chicks from hatching to 4 weeks of
age, 300 p/m nickel as nickel carbonate
or nickel acetate in the diet produced no
observed adverse effects, but
concentrations of 500 p/m or more
reduced growth (Weber and Reid 1968).
A diet containing 200 p/m nickel as
nickel sulfate had no observed effects on
mallard ducklings from 1 to 90 days of
PO 00000
Frm 00042
Fmt 4702
Sfmt 4702
49549
age. Diets of 800 p/m or more caused
significant changes in physical
condition of the ducklings (Cain and
Pafford 1981).
Mallard ducklings fed 1,200 p/m
nickel as nickel sulfate from 1 to 90
days of age experienced reduced growth
rates, tremors, paresis, and death (71
percent within 60 days) (Cain and
Pafford 1981). Weights of ducklings
receiving 200 and 800 p/m nickel were
not significantly different than controls,
but the humerus weight/length ratio, a
measure of bone density, was
significantly lower than controls among
females in the 800 p/m group and all
birds in the 1,200 p/m group. There was
no mortality in the 200 and 800 p/m
groups.
Breeding pairs of mallards were fed
diets containing 0, 12.5, 50, 200, and
800 p/m nickel as nickel sulfate for 90
days (Eastin and O’Shea 1981). No
treatment-related effects were observed
on egg production, hatchability, or
survival of ducklings. At the end of the
90-day treatment period, there were no
significant differences in hematocrit,
concentrations of hemoglobin, plasma
triglycerides, cholesterol, or plasma
activities of ornithine carbamoyl
transferase and alanine
aminotransferase. The only treatmentrelated observation was a black, tarry
feces in the 800 p/m group. Assuming
a mean daily consumption of 128 grams
per bird (Heinz 1979), the 800 p/m
treatment group would have consumed
102 mg nickel each day and 9.2 grams
of nickel during the course of the 90-day
study. In the nontoxic shot Tier 2
approval process, birds could be given
eight number 4 shot. For ITN shot, each
shot would contain 0.02206 grams of
nickel, so each duck would receive
0.176 grams of nickel, assuming
complete solubilization of the nickel
from the shot during the study. This is
a very small fraction of the 9.2 grams of
total nickel exposure or 102 mg per day
experienced by the mallards in the
Eastin and O’Shea (1981) study.
Therefore, we expect no effect of the
nickel on birds ingesting the shot.
No reproductive or other effects were
observed in mallards consuming the
equivalent of 102 mg of nickel as nickel
sulfate each day for 90 days (Eastin and
O’Shea 1981). Therefore, the 15.3 mg of
nickel in each TICN shot, if completely
eroded and absorbed in 24 hours, would
not be expected to affect waterfowl.
Based on the 0.221 mg of nickel per shot
per day rate of release from the
solubility study, a mallard would have
to ingest in excess of 450 TICN shot to
exceed the 102 mg nickel amount.
Additionally, metallic nickel likely has
a lower absorption from the
E:\FR\FM\24AUP1.SGM
24AUP1
49550
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
gastrointestinal tract than does the
nickel sulfate used in the mallard
reproduction study, further decreasing
the absorbed dose of TICN shot
compared to the published toxicity
study described above.
Adult mallards dosed with eight
tungsten-nickel-iron number 4 pellets
were fed a whole kernel corn and grit
and observed for signs of toxicity for 30
days following dosing (January 4, 2001;
66 FR 737). No adverse effects were
observed on body weight, food
consumption or clinical chemistry,
hematology, and histopathology. The
tungsten-nickel-iron pellets lost an
average of 7.9 percent of their initial
weight during the study, releasing
nickel at a rate of 1.85 mg per day per
bird, for a total of 55.5 mg over the 30day study.
In a Tier 2 dosing study under the
regulations governing approval of
nontoxic shot, mallard ducks would
each be given eight number 4 TICN shot
(each containing 0.02206 grams of
nickel) during the study. A duck would
be exposed to 0.176 grams of nickel
during the study if the nickel were
completely dissolved. This is much less
than the nickel exposure experienced by
the mallards in the Eastin and O’Shea
(1981) study. We conclude that the
nickel in TICN shot will not be
significant to waterfowl that ingest the
shot.
Water hardness is the dominant factor
governing nickel effects on aquatic biota
(Stokes 1988). Toxicity of nickel to
aquatic organisms is dependent upon
water hardness, pH, and organic
content, as well as other minor
environmental parameters (Allen and
Hansen 1996). In soft water, as little as
7 p/b nickel may be acutely toxic to fish
fry, while in harder waters toxicity
thresholds may be an order of
magnitude higher (Stokes 1988).
The EPA (1986) acute water quality
criteria reflect this insensitivity of
aquatic organisms to nickel. For a water
body with hardness of 50 mg/l
(generally associated with highly
oligotrophic systems that would not
support large numbers of waterfowl),
the criterion is 1,400 µg/l. However,
early fish life stages are more sensitive
to nickel (Stokes 1988), which is
reflected in the order of magnitude
lower Freshwater Chronic Criterion of
160 µg/l at a hardness of 50 mg/l (EPA
1986).
The saltwater chronic criterion of 8.3
µg/l is much lower than the measured
mysid shrimp (Mysidopsis bahia)
chronic value, which is from the only
chronic saltwater study in the EPA
guidelines (EPA 1986).
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
30-day dosing study of game-farm
mallards dosed with eight number 4 size
tin shot, there were no overt signs of
toxicity or treatment-related effects on
body weight. Tin was not detected in
any tissues (Gallagher et al. 1999).
The 2 percent tin in bismuth-tin shot
produced no toxicological effects in
ducks during reproduction. It did not
affect the health of ducks, the
reproduction by male and female birds,
or the survival of ducklings over the
long term (Sanderson et al. 1997).
Chronic and acute studies
documenting the nontoxic properties of
99.9 percent tin shot were conducted for
the application for USFWS approval of
tin shot as a nontoxic alternative. A 150day chronic toxicity/reproductive study
conducted for tin shot revealed no
adverse effects in mallards dosed with
eight number 4 sized shot. Additionally,
there were no significant changes in egg
production, fertility, or hatchability of
birds dosed with tin when compared to
steel-dosed birds. A 30-day acute study
was also completed by the International
Tin Research Institute (Federal Register
64:17308, 1999). Treatment mallards
Tin
were dosed with eight number 4 tin shot
It is generally agreed that inorganic
and hematocrit and hemoglobin
tin and tin compounds are
concentrations, body weight and
comparatively harmless (Eisler 1989).
indications of toxicity were compared to
Inorganic tin and its salts are poorly
those of control (no shot) and steel shotabsorbed, their oxides are relatively
dosed birds. No adverse effects were
insoluble, and they are rapidly lost from seen in ducks dosed with tin.
tissues (see Eisler 1989 for reviews).
Hematocrit and hemoglobin
Reviews indicate that elemental tin is
concentrations did not differ from those
not toxic to birds (Cooney 1988,
of either negative control group, nor
Eisler1989). Tin shot designed for
were there treatment-related effects on
waterfowl hunting is used in several
body weight. Ducks dosed with tin
European countries. We are aware of no exhibited no sign of toxicity.
In a study by Kraabel et al. (1996),
reports that suggest that tin shot causes
shot pellets containing 39 percent
toxicity problems for wildlife.
tungsten, 44.5 percent bismuth, and
Tin (II) chloride was toxic to juvenile
eels at 6.0 mg/l and 1.2 mg/l, with death 16.5 percent tin were embedded into the
breast muscle of mallards. There were
coming at 2.8 and 50 hours,
respectively. This inorganic tin salt was no adverse systemic effects observed in
also toxic to daphnids, at concentrations the study and the localized
of 2.5 mg/l or more. Metelev et al. (1971) inflammatory reactions surrounding the
shot were reduced in the tin-containing
found that 1 g/l of Tin (II) chloride
shot when compared to the steel shot
dihydrate (530 mg of tin per liter) was
control group.
lethal to all fish species tested
Based on the toxicological report and
(Bandman 1993).
toxicity tests, we concluded that shot
Grandy et al. (1968) and the
that was 99.9 percent tin posed no
Huntingdon Research Centre (1987)
significant danger to migratory birds or
conducted 30-day and 28-day,
other wildlife and their habitats (65 FR
respectively, acute toxicity tests on
76886, December 7, 2000). Temporary
mallard ducks by placing tin pellets
approval was given because field
inside the digestive tract or tissues of
detection techniques had not been
ducks. They reported that all treated
approved, not due to any toxicity
ducks survived without deleterious
concerns. In support of the nontoxic
effects.
application, chronic and acute toxicity
Ringelmann et al. (1993) examined
tests demonstrated no adverse effects of
the effects of Tungsten-Bismuth-Tin
shot consumption in ducks. The authors tin shot on mallards. We do not believe
the tin in any of the proposed shot types
found no signs of toxicosis, and tin was
that contain it will pose toxicological
not detected in the liver or kidney (<6
risks due to wildlife.
p/m) during the 32-day test period. In a
Toxicity of nickel to aquatic
organisms is dependent upon water
hardness, pH, and organic content, as
well as other minor environmental
parameters (Allen and Hansen 1996). In
soft water, as few as 7 p/b may be
acutely toxic to fish fry, but in harder
waters toxicity thresholds may be an
order of magnitude higher. General
toxicity ranges for aquatic organisms are
as variable, with an acute toxicity of as
low as 82 µg/l for some oligochaetes to
138,000 µg/l for some gastropods;
chronic toxicity values range from fewer
than 100 µg/l for some green algae to
10,000 µg/l for filamentous algae (Stokes
1988).
The freshwater criterion maximum
concentration is dependent on hardness.
For a water body with hardness of 50
mg/l (generally associated with highly
oligotrophic systems that would not
support large numbers of waterfowl),
this results in a criterion of 1,400 µg/l.
However, because early fish life stages
are more sensitive to nickel, the
freshwater chronic criterion is 160 µg/l
at a hardness of 50 mg/l (EPA 1986).
PO 00000
Frm 00043
Fmt 4702
Sfmt 4702
E:\FR\FM\24AUP1.SGM
24AUP1
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
Cumulative Impacts
Impacts of Approval of Alloys of
Previously Approved Metals
We propose to extend the past
approvals of some nontoxic shot types
to broader alloys. We have, for example,
approved nontoxic shot of almost 100
percent tungsten, and steel shot is
essentially 100 percent iron. We are not
aware of any synergistic effects of these
metals, and approval of other shot types
containing them in different proportions
has indicated that negative effects on
wildlife, fish, or their habitats from
approval of alloys of these metals are
very unlikely. Therefore, we propose to
approve alloys containing any
proportion of tungsten and 1 percent or
more iron.
Similarly, as noted above, we gave
temporary approval to shot of 100
percent tin (65 FR 76885), though the
submitter did not seek final approval of
that shot type. We also propose to
approve shot alloys with any
proportions of tungsten and tin and at
least 1 percent iron.
Effects of the Approvals on Migratory
Waterfowl
Approving additional nontoxic shot
types will likely result in a minor
positive long-term impact on waterfowl
and wetland habitats. Approval of the
four shot types and additional alloys as
nontoxic would have a positive impact
on the waterfowl resource.
Effects on Endangered and Threatened
Species
The impact on endangered and
threatened species of approval of the
four shot types and the additional alloys
would be very small, but positive. The
metals in all four shot types and the
additional alloys have been approved in
other nontoxic shot types, and we see
no potential effects on threatened or
endangered species due to approval of
these shot types.
Effects on Ecosystems
Previously approved shot types have
been shown in test results to be
nontoxic to the migratory bird resource,
and we believe that they cause no
adverse impact on ecosystems. There is
concern, however, about noncompliance
and potential ecosystem effects. The use
of lead shot has a negative impact on
wetland ecosystems due to the erosion
of shot, causing sediment/soil and water
contamination and the direct ingestion
of shot by aquatic and predatory
animals. Though we believe
noncompliance is of concern, approval
of the four shot types and the additional
alloys will have little impact on the
resource.
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
We foresee no negative cumulative
impacts of approval of the four shot
types and the additional alloys for
waterfowl hunting. Their approval
should help to further reduce the
negative impacts of the use of lead shot
for hunting waterfowl and coots.
Literature Cited
For a complete list of the literature
cited in this proposed rule, contact the
person listed under FOR FURTHER
INFORMATION CONTACT.
Public Comments
In accordance with the
Administrative Procedures Act and our
nontoxic shot approval regulations, we
seek comments on this proposal. Of
particular relevance is information
regarding the potential impacts of these
shot types and the approval of alloys of
metals already approved in other
formulations on migratory birds, other
wildlife, and their habitats.
In addition, Executive Order 12866
requires each agency to write
regulations that are easy to understand.
We invite comments on how to make
this rule easier to understand, including
answers to questions such as the
following: (1) Are the requirements in
the rule clearly stated? (2) Does the rule
contain technical language or jargon that
interferes with its clarity? (3) Does the
format of the rule (grouping and order
of sections, use of headings,
paragraphing, etc.) aid or reduce its
clarity? (4) Would the rule be easier to
understand if it were divided into more
(but shorter) sections? (A ‘‘section’’
appears in bold type and is preceded by
the symbol ‘‘§ ’’ and a numbered
heading; for example, ‘‘§ 20.134
Approval of nontoxic shot types.’’) (5) Is
the description of the rule in the
SUPPLEMENTARY INFORMATION section of
the preamble helpful in understanding
the rule? What else could we do to make
the rule easier to understand?
You may submit written comments on
this proposal to the location identified
in the ADDRESSES section, or you may
submit electronic comments to the
internet address or the e-mail address
listed in the ADDRESSES section. We
must receive your comments before the
date listed in the DATES section. While
our normal practice is to open public
comment periods on our proposed rules
for 60 days, in this case we are opening
the comment period for only 30 days.
We believe a 30-day comment period
will be sufficient because we have
approved several other nontoxic shot
types through the rulemaking process
and have received very few comments
PO 00000
Frm 00044
Fmt 4702
Sfmt 4702
49551
on those rulemaking actions and
because the changes in this proposed
rule should not be controversial.
Following review and consideration of
comments, we will issue a final rule on
the proposed regulation changes.
When submitting electronic
comments, please include your name
and return address in your message,
identify it as comments on the nontoxic
shot proposed rule, and submit your
comments as an ASCII file, preferably as
part of the e-mail text. Include RIN
1018–AU04 in the subject line of your
message. Do not use special characters
or any encryption. Written comments on
this proposed rule must be on 81⁄2-inch
by 11-inch paper.
We make comments, including names
and home addresses of respondents,
available for public review during
regular business hours. Individual
respondents may request that we
withhold their home address from the
rulemaking record, which we will honor
to the extent allowable by law. In some
circumstances, we would withhold from
the rulemaking record a respondent’s
identity, as allowable by law. If you
wish us to withhold your name or
address, you must state this
prominently at the beginning of your
comment. We will not accept
anonymous comments. We will make all
submissions from organizations or
businesses, and from individuals
identifying themselves as
representatives or officials of
organizations or businesses, available
for public inspection in their entirety.
Comments will become part of the
Administrative Record for the review of
the application. You may inspect
comments at the mailing address in
ADDRESSES during normal business
hours.
The Draft Environmental Assessment
(DEA) for approval of the four shot types
is available from the Division of
Migratory Bird Management, U.S. Fish
and Wildlife Service, 4501 North Fairfax
Drive, Room 4091, Arlington, VA
22203–1610. You may call 703–358–
1825 to request a copy of the DEA.
The complete file for this rule is
available, by appointment, during
normal business hours at the same
address. You may make an appointment
at 703–358–1825 to review the files.
Required Determinations
NEPA Consideration
In compliance with the requirements
of section 102(2)(C) of the National
Environmental Policy Act of 1969 (42
U.S.C. 4332(C)), and the Council on
Environmental Quality’s regulations for
implementing NEPA (40 CFR 1500–
E:\FR\FM\24AUP1.SGM
24AUP1
49552
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
1508), though all of the metals in these
shot types have been approved in other
shot types and are not likely to pose
adverse toxicity effects on fish, wildlife,
their habitats, or the human
environment, we have prepared Draft
Environmental Assessments for this
action. We will finalize the
Environmental Assessments before we
publish a final rule on this action.
Endangered Species Act Considerations
Section 7 of the Endangered Species
Act (ESA) of 1972, as amended (16
U.S.C. 1531 et seq.), provides that
Federal agencies shall ‘‘insure that any
action authorized, funded or carried out
* * * is not likely to jeopardize the
continued existence of any endangered
species or threatened species or result in
the destruction or adverse modification
of (critical) habitat.’’ We have concluded
that because all of the metals in these
shot types have been approved in other
shot types and will not be available to
biota in significant amounts due to use
of any of the four shot types, this action
will not affect endangered or threatened
species.
Executive Order 12866
This rule is not a significant
regulatory action subject to Office of
Management and Budget (OMB) review
under Executive Order 12866. This rule
will not have an annual economic effect
of $100 million or more or adversely
affect an economic sector, productivity,
jobs, the environment, or other units of
government. Therefore, a cost-benefit
economic analysis is not required. This
action will not create inconsistencies
with other agencies’ actions or
otherwise interfere with an action taken
or planned by another agency. No other
Federal agency has any role in
regulating nontoxic shot for migratory
bird hunting. The action is consistent
with the policies and guidelines of other
Department of the Interior bureaus. This
action will not materially affect
entitlements, grants, user fees, loan
programs, or the rights and obligations
of their recipients because it has no
mechanism to do so. This action will
not raise novel legal or policy issues
because the Service has already
approved several other nontoxic shot
types.
Regulatory Flexibility Act
The Regulatory Flexibility Act of 1980
(5 U.S.C. 601 et seq.) requires the
preparation of flexibility analyses for
rules that will have a significant
economic impact on a substantial
number of small entities, which include
VerDate jul<14>2003
12:45 Aug 23, 2005
Jkt 205001
small businesses, organizations, or
governmental jurisdictions. This rule
proposes to approve four additional
types of nontoxic shot that may be sold
and used to hunt migratory birds. We
have determined, however, that this rule
will have no effect on small entities
since the approved shot merely will
supplement nontoxic shot types already
in commerce and available throughout
the retail and wholesale distribution
systems. We anticipate no dislocation or
other local effects, with regard to
hunters and others.
Small Business Regulatory Enforcement
Fairness Act
This proposed rule is not a major rule
under 5 U.S.C. 804(2), the Small
Business Regulatory Enforcement
Fairness Act. This rule will not have an
annual effect on the economy of $100
million or more; will not cause a major
increase in costs or prices for
consumers, individual industries,
Federal, State, or local government
agencies, or geographic regions; and
does not have significant adverse effects
on competition, employment,
investment, productivity, innovation, or
the ability of U.S.-based enterprises to
compete with foreign-based enterprises.
the applicable standards provided in
Sections 3(a) and 3(b)(2) of Executive
Order 12988.
Takings
In accordance with Executive Order
12630, this rule, authorized by the
Migratory Bird Treaty Act, does not
have significant takings implications
and does not affect any constitutionally
protected property rights. This rule will
not result in the physical occupancy of
property, the physical invasion of
property, or the regulatory taking of any
property. A takings assessment is not
required.
Federalism Effects
This rule does not have a substantial
direct effect on fiscal capacity, change
the roles or responsibilities of Federal or
State governments, or intrude on State
policy or administration. In accordance
with Executive Order 13132, this
regulation does not have significant
federalism effects, nor does it have
sufficient federalism implications to
warrant the preparation of a Federalism
Assessment.
Government-to-Government
Relationship With Tribes
Paperwork Reduction Act
An agency may not conduct or
sponsor, and a person is not required to
respond to, a collection of information
unless it displays a currently valid OMB
control number. We have examined this
regulation under the Paperwork
Reduction Act of 1995 (44 U.S.C. 3501)
and found it to contain no new
information collection requirements.
OMB has assigned control number
1018–0067 to the collection of
information that shot manufacturers are
required to provide to us for the
nontoxic shot approval process. This
approval expires December 31, 2006.
For further information, see 50 CFR
20.134.
In accordance with the President’s
memorandum of April 29, 1994,
‘‘Government-to-Government Relations
with Native American Tribal
Governments’’ (59 FR 22951) and 512
DM 2, we have determined that this rule
has no effects on Federally recognized
Indian tribes.
Unfunded Mandates Reform
We have determined and certify
pursuant to the Unfunded Mandates
Reform Act, 2 U.S.C. 1502 et seq., that
this rulemaking will not significantly or
uniquely affect small governments or
produce a Federal mandate of $100
million or more in any given year.
Therefore, this rule does not constitute
a significant regulatory action under the
Unfunded Mandates Reform Act.
PART 20—[AMENDED]
Civil Justice Reform—Executive Order
12988
In promulgating this rule, we have
determined that these regulations meet
PO 00000
Frm 00045
Fmt 4702
Sfmt 4702
List of Subjects in 50 CFR Part 20
Exports, Hunting, Imports, Reporting
and recordkeeping requirements,
Transportation, Wildlife.
For the reasons discussed in the
preamble, we propose to amend part 20,
subchapter B, chapter I of Title 50 of the
Code of Federal Regulations as follows:
1. The authority citation for part 20
continues to read as follows:
Authority: 16 U.S.C. 703–712; 16 U.S.C.
742a–j; Pub. L. 106–108.
2. Section 20.21 is proposed to be
amended by revising paragraph (j)(1) to
read as follows:
§ 20.21
What hunting methods are illegal?
*
*
*
*
*
(j)(1) While possessing loose shot for
muzzle loading or shotshells containing
other than the following approved shot
types.
E:\FR\FM\24AUP1.SGM
24AUP1
Federal Register / Vol. 70, No. 163 / Wednesday, August 24, 2005 / Proposed Rules
Approved shot type
Percent composition by weight
bismuth-tin ..........................................................
iron (steel) ..........................................................
iron-tungsten ......................................................
iron-tungsten-nickel. ...........................................
97 bismuth, 3 tin ..............................................
iron and carbon ................................................
any proportion of tungsten, ≥ 1 iron ................
≥ 1 iron, any proportion of tungsten, up to 40
nickel
51.1 tungsten, 44.4 copper, 3.9 tin, 0.6 iron
and 60 tungsten, 35.1 copper, 3.9 tin, 1
iron.
40–76 tungsten, 10–37 iron, 9–16 copper, 5–7
nickel
95.9 tungsten, 4.1 polymer ..............................
95.5 tungsten, 4.5 Nylon 6 or 11 .....................
any proportions of tungsten and tin, ≥ 1 iron.
49–71 tungsten, 29–51 tin; 0.5–6.5 bismuth,
0.8 iron.
65 tungsten, 21.8 tin, 10.4 iron, 2.8 nickel ......
tungsten-bronze .................................................
tungsten-iron-copper-nickel. ...............................
tungsten-matrix ..................................................
tungsten-polymer ...............................................
tungsten-tin-iron .................................................
tungsten-tin-bismuth ...........................................
tungsten-tin-iron-nickel .......................................
Field testing device
Hot Shot*.
Magnet or Hot Shot.
Magnet or Hot Shot.
Magnet or Hot Shot.
Rare Earth Magnet.
Hot Shot or Rare Earth Magnet.
Hot Shot.
Hot Shot.
Magnet or Hot Shot.
Rare Earth Magnet.
Magnet.
* The information in the ‘‘Field Testing Device’’ column is strictly informational, not regulatory.
** The ‘‘Hot Shot’’ field testing device is from Stream Systems of Concord, CA.
*
*
*
*
*
Dated: July 26, 2005.
Craig Manson,
Assistant Secretary for Fish and Wildlife and
Parks.
[FR Doc. 05–16718 Filed 8–23–05; 8:45 am]
BILLING CODE 4310–55–P
VerDate jul<14>2003
15:01 Aug 23, 2005
Jkt 205001
PO 00000
Frm 00046
Fmt 4702
Sfmt 4702
E:\FR\FM\24AUP1.SGM
24AUP1
49553
]]>Agencies
[Federal Register Volume 70, Number 163 (Wednesday, August 24, 2005)]
[Proposed Rules]
[Pages 49541-49553]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-16718]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 20
RIN 1018-AU04; 1018-AU 09; 1018-AU13; 1018-AU28
Migratory Bird Hunting; Approval of Tungsten-Iron-Copper-Nickel,
Iron-Tungsten-Nickel Alloy, and Tungsten-Bronze (Additional
Formulation), and Tungsten-Tin-Iron Shot Types as Nontoxic for Hunting
Waterfowl and Coots; Availability of Environmental Assessments
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Proposed rule; notice of availability.
-----------------------------------------------------------------------
SUMMARY: The U.S. Fish and Wildlife Service (we, us, or USFWS) proposes
to approve four shot types or alloys for hunting waterfowl and coots
and to change the listing of approved nontoxic shot types in 50 CFR
20.21(j) to reflect the cumulative approvals of nontoxic shot types and
alloys.
These four shot types or alloys were submitted to us separately,
and we published advance notices of proposed rulemakings for these shot
types under RINs 1018-AU04, 1018-AU09, 1018-AU13, and 1018-AU28,
respectively. We now combine all these actions under RIN 1018-AU04.
In addition, we propose to approve alloys of several metals because
we have approved the metals individually at or near 100% in nontoxic
shot.
DATES: Send comments on this proposal by September 23, 2005.
ADDRESSES: You may submit comments, identified by RIN 1018-AU04, by any
of the following methods:
Federal eRulemaking Portal: https://www.regulations.gov.
Follow the instructions for submitting comments.
Agency Web Site: https://migratorybirds.fws.gov. Follow the
links to submit a comment.
E-mail address for comments: George--T--Allen@fws.gov.
Include ``RIN 1018-AU04'' in the subject line of the message. Please
submit electronic comments as text files; do not use file compression
or any special formatting.
Fax: 703-358-2217.
Mail: Chief, Division of Migratory Bird Management, U.S.
Fish and Wildlife Service, 4401 North Fairfax Drive, Mail Stop MBSP-
4107, Arlington, Virginia 22203-1610.
Hand Delivery: Division of Migratory Bird Management, U.S.
Fish and Wildlife Service, 4501 North Fairfax Drive, Room 4091,
Arlington, Virginia 22203-1610.
For specific instructions on submitting or inspecting public
comments, inspecting the complete file for this rule, or requesting a
copy of the draft environmental assessment, see Public Comments in
SUPPLEMENTARY INFORMATION.
FOR FURTHER INFORMATION CONTACT: Dr. George T. Allen, Division of
Migratory Bird Management, 703-358-1714.
SUPPLEMENTARY INFORMATION:
Background
The Migratory Bird Treaty Act of 1918 (Act) (16 U.S.C. 703-711) and
the Fish and Wildlife Improvement Act of 1978 (16 U.S.C. 712) implement
migratory bird treaties between the United States and Great Britain for
Canada (1916, amended), Mexico (1936, amended), Japan (1972, amended),
and Russia (then the Soviet Union, 1978). These treaties protect
certain migratory birds from take, except as permitted under the Acts.
The Acts authorize the Secretary of the Interior to regulate take of
migratory birds in the United States. Under this authority, the U.S.
Fish and Wildlife Service controls the hunting of migratory game birds
through regulations in 50 CFR part 20.
Deposition of toxic shot and release of toxic shot components in
waterfowl hunting locations are potentially harmful to many organisms.
Research has shown that ingested spent lead shot causes significant
mortality in migratory birds. Since the mid-1970s, we have sought to
identify shot types that do not pose significant toxicity hazards to
migratory birds or other wildlife. We addressed the issue of lead
poisoning in waterfowl in an Environmental Impact Statement in 1976,
and again in a 1986 supplemental EIS. The 1986 document provided the
scientific justification for a ban on the use of lead shot and the
subsequent approval of steel shot for hunting waterfowl and coots that
began that year, with a complete ban of lead for waterfowl and coot
hunting in 1991. We have continued to consider other potential
candidates for approval as nontoxic shot. We are obligated to review
applications for approval of alternative shot types as nontoxic for
hunting waterfowl and coots.
We have received applications for approval of four shot types as
nontoxic for hunting waterfowl and coots. Those shot types are:
1. Tungsten-Iron-Copper-Nickel (TICN) shot, of 40-76 percent
tungsten, 10-37 percent iron, 9-16 percent copper, and 5-7 percent
nickel (70 FR 3180, January 21, 2005);
2. Iron-Tungsten-Nickel (ITN) alloys composed of 20-70 percent
tungsten, 10-40 percent nickel, and 10-70 percent iron (70 FR 22625,
May 2, 2005);
3. Tungsten-Bronze (TB) shot made of 60 percent tungsten, 35.1
percent copper, 3.9 percent tin, and 1 percent iron (70 FR 22624, May
2, 2005, Note: This formulation differs from the Tungsten-Bronze
nontoxic shot formulation approved in 2004.); and
4. Tungsten-Tin-Iron (TTI) shot composed of 58 percent tungsten, 38
percent tin, and 4 percent iron.
The metals in these shot types have already been approved in other
nontoxic shot types. In considering approval of these shot types, we
were particularly concerned about the solubility and bioavailability of
the nickel and copper in them. In addition, because tungsten, tin, and
iron have already been approved at very high proportions of other
nontoxic shot types with no known negative effects of the metals, we
will propose approval of all alloys of these four metals.
The data provided to us indicate that the shot types are nontoxic
when ingested by waterfowl and should not pose a significant danger to
migratory birds, other wildlife, or their habitats. We conclude that
they raise no particular concerns about deposition in the environment
or about ingestion by waterfowl or predators.
The process for submission and evaluation of new shot types for
approval as nontoxic is given at 50 CFR 20.134. The list of shot types
approved as nontoxic for use in hunting migratory birds is provided in
the table at 50 CFR 20.21(j). With this proposed rule, we also propose
to revise the listing of approved nontoxic shot types in Sec. 20.21(j)
to include the cumulative approvals of the shot types considered in
this proposed rule with the other nontoxic shot types already in the
table.
Many hunters believe that some nontoxic shot types do not compare
favorably to lead and that they may damage some shotgun barrels, and a
small percentage of hunters have not complied with nontoxic shot
regulations. Allowing use of additional nontoxic shot types may
encourage greater hunter compliance and participation with nontoxic
shot requirements and discourage the use of lead shot. The use of
nontoxic shot for waterfowl hunting has increased in recent years
(Anderson et al. 2000), but we believe that compliance will continue to
increase with the availability and approval of other
[[Page 49542]]
nontoxic shot types. Increased use of nontoxic shot will enhance
protection of migratory waterfowl and their habitats. More important,
however, is that the Fish and Wildlife Service is obligated to consider
all complete nontoxic shot submissions.
We also propose to add a column to the table of approved shot types
that lists the field testing device suitable for each shot type. The
information in this column is strictly informational, not regulatory.
Because these regulations are used by both waterfowl hunters and law
enforcement officers, we believe that information on suitable testing
devices is a useful addition to the table.
Affected Environment
Waterfowl Populations
The taxonomic family Anatidae, principally subfamily Anatinae
(ducks) and their habitats, comprise the affected environment.
Waterfowl habitats and populations in North America in 2004 were
described by the U.S. Fish and Wildlife Service (Garrettson et al.
2004). In the Breeding Population and Habitat Survey traditional survey
area (strata 1-18, 20-50, and 75-77), the total-duck population
estimate was 32.2 0.6 ( 1 standard error)
million birds, 11 percent below the 2003 estimate of 36.2
0.7 million birds, and 3 percent below the 1955-2003 long-term average.
Mallards (Anas platyrhynchos) were estimated at 7.4 0.3
million, similar to last year's estimate of 7.9 0.3
million birds and to the long-term average. Blue-winged teal (A.
discors) numbered 4.1 0.2 million, 26 percent below last
year's estimate of 5.5 0.3 million and 10 percent below
the long-term average. Among other duck species, only northern
shovelers (A. clypeata, 2.8 0.2 million) and American
wigeon (A. americana, 2.0 0.1 million) were both 22
percent below their 2003 estimates. As in 2003, gadwall (A. strepera,
2.6 0.2 million, +56 percent), green-winged teal (A.
crecca, 2.5 0.1 million, +33 percent), and northern
shovelers (+32 percent) were above their long-term averages. Northern
pintails (A. acuta, 2.2 0.2 million, -48 percent), scaup
(Aythya affinis and A. marila, 3.8 0.2 million, -27
percent), and American wigeon (-25 percent) were well below their long-
term averages in 2004.
Habitats
Waterfowl hunting occurs in habitats used by many taxa of migratory
birds, as well as by aquatic invertebrates, amphibians and some
mammals. Fish also may be found in many hunting locations. In 2004,
total May ponds in Prairie Canada, and the north-central United States
combined were estimated at 3.9 0.2 million, which was 24
percent lower than the figure for 2003 and 19 percent below the long-
term average. Pond numbers in both Canada (2.5 0.1
million) and the U. S. (1.4 0.1 million) were below 2003
estimates (-29 percent in Canada, and -16 percent in the United
States), and pond numbers in Canada were 25 percent below the long-term
average for the region.
Fall Flight Forecasts
The projected mallard fall flight index was 9.4 0.1
million birds, similar to the 2003 estimate of 10.3 0.1
million. The 2004 total duck population estimate for the eastern survey
area (strata 51-56 and 62-69) was 3.9 0.3 million birds.
This estimate was similar to the 2003 estimate of 3.6 0.3
million birds, and to the 1996-2003 average. Individual species
estimates for this area were similar to 2003 estimates and to 1996-2003
averages, with the exception of American wigeon (0.1 0.1
million) and goldeneyes (Bucephala clangula and B. islandica, 0.4
0.1 million), which were 61 percent and 42 percent below
their 1996-2003 averages, respectively, and ring-necked ducks (Aythya
collaris, 0.7 0.2 million), which increased by 67 percent
relative to the 2003 estimate of their numbers.
Characterization of the Four Shot Types
TICN Alloys
Spherical Precision, Inc. of Tustin, CA, submitted Tungsten-Iron-
Copper-Nickel (TICN) shot for approval. The advance notice of proposed
rulemaking for this group of alloys was published in the Federal
Register on January 21, 2005, under RIN 1018-AU04 (70 FR 3180). This is
an array of layered alloys or metals of 40-76 percent tungsten, 10-37
percent iron, 9-16 percent copper, and 5-7 percent nickel. TICN shot
has a density ranging from 10.0 to 14.0 grams per cubic centimeter (g/
cm3), is noncorrosive, and is magnetic. Spherical Precision
estimates that the volume of TICN shot for use in hunting migratory
birds in the United States will be approximately 50,000 pounds (lb)
(22,700 kilograms (kg)) during the first year of sale, and perhaps
100,000 lb (45,400 kg) per year thereafter.
ITN Alloys
ENVIRON-Metal of Sweet Home, OR, submitted Iron-Tungsten-Nickel
(ITN) alloys, which are cast alloys containing 10-70 percent iron, 20-
70 percent tungsten, and 10-40 percent nickel. The advance notice of
proposed rulemaking for this group of alloys published in the Federal
Register on May 2, 2005, under RIN 1018-AU09 (70 FR 22625). The
proposed shot types have densities ranging from about 8.5 to about 13.5
g/cm3. The compositions of the alloys are shown in table 1.
Table 1.--Composition of ITN Shot Alloys
--------------------------------------------------------------------------------------------------------------------------------------------------------
Iron Tungsten Nickel
Density (g/ Shot weight -----------------------------------------------------------------------------
Alloy cm\3\) \1\ (mg) \2\ Weight Weight Weight
Percent (mg) Percent (mg) Percent (mg)
--------------------------------------------------------------------------------------------------------------------------------------------------------
1............................................... 8.8 165.89 70 116.12 20 33.18 10 16.59
2............................................... 9.0 169.65 40 67.86 20 67.86 40 33.93
3............................................... 9.8 184.73 44 81.28 33 60.96 23 42.49
4............................................... 11.3 213.00 10 21.30 50 106.50 40 85.20
5............................................... 13.3 250.71 20 50.14 70 175.49 10 25.07
6............................................... 13.55 255.42 10 25.54 70 178.79 20 51.08
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note.--Weights are based on one number 4 shot.
ENVIRON-Metal estimated that the yearly volume of ITN shot types
with densities between those of steel (7.86 g/cm3) and lead
(11.3 g/cm3) expected for use in hunting migratory birds in
the United States is approximately 200,000 lb (113,500 kg) during the
first year of sale. In the second year and beyond, sales upwards of
500,000 lb (227,000 kg) per year are anticipated. ITN shot types with
densities greater than that of lead may ultimately attain sales levels
of 1,000,000 lb (454,000 kg) per year.
[[Page 49543]]
TB Shot
The Olin Corporation of East Alton, IL, submitted Tungsten-Bronze
(TB) shot for approval. The advance notice of proposed rulemaking for
this shot type was published in the Federal Register on May 2, 2005,
under RIN 1018-AU13 (70 FR 22624). This is a sintered composite with an
average composition of 60 percent tungsten, 35.1 percent copper, 3.9
percent tin, and 1 percent iron. The copper and tin make up 39 percent
of the shot as a 90:10 ratio, respectively, in the form of a bronze
alloy. The shot has a density of 12.0 g/cm3, compared to
11.1-11.3 g/cm3 for lead, and 7.9 g/cm3 for
steel. Olin estimated that the yearly volume of the TB shot in hunting
migratory birds in North America will be approximately 300,000 lb
(136,200 kg).
TTI Shot
Tungsten-Tin-Iron (TTI) shot, submitted by Nice Shot, Inc., of
Albion, PA, is a cast alloy composed of 58 percent tungsten, 38 percent
tin, and 4 percent iron. This shot type has a density of 11.0 g/
cm3. Nice Shot, Inc. estimated that approximately 5,000 lb
(2,270 kg) of TTI shot are expected to be sold for use in hunting
migratory birds in the United States during the first year of sale. TTI
shot contains less than 1 percent lead, and will not be coated.
Each of the four shot types has a residual lead level of less than
1 percent. To inhibit corrosion, TICN shot may be coated with tin, and
ITN shot may be surface-coated with thin petroleum-based films. Neither
TB nor TTI shot will be coated.
Environmental Fate of the Metals in the Four Shot Types
All of the metals in these shot types have been approved in other
nontoxic shot types, and the submitters asserted that the four shot
types pose no adverse toxicological risks to waterfowl or other forms
of terrestrial or aquatic life. Our particular concern in considering
approval of these shot types is the solubility and bioavailability of
the nickel and copper in them.
The metals in the four shot types are insoluble under hot and cold
(Weast 1986). Neither manufacturing the shot nor firing shotshells
containing the shot will alter the metals or change how they dissolve
in the environment. The shot types are not chemically or physically
altered by firing from a shotgun.
Iron is naturally widespread. It comprises approximately 2 percent
of the composition of soils and sediments in the United States. The
iron in the shot types is not soluble.
Elemental tungsten and iron are virtually insoluble in water, and
therefore do not weather and degrade in the environment. Tungsten is
stable in acids and does not easily form compounds with other
substances. Preferential uptake by plants in acidic soil suggests
uptake of tungsten when it has formed compounds with other substances
rather than when it is in its elemental form (Kabata-Pendias and
Pendias 1984).
Elemental copper can be oxidized by organic and mineral acids that
contain an oxidizing agent. Elemental copper is not oxidized in water
(Aaseth and Norseth 1986).
Nickel is common in fresh waters, though usually at concentrations
of less than 1 part per billion (p/b) in locations unaffected by human
activities. Pure nickel is not soluble in water, and resists corrosion
at temperatures between -20 [deg]C and 30 [deg]C (Chau and Kulikovsky-
Cordeiro 1995). Free nickel may be part of chemical reactions, such as
sorption, precipitation, and complexation. ``Under anaerobic
conditions, typical of deep groundwater, precipitation of nickel
sulfide keeps nickel concentrations low'' (Eisler 1998). Reactions of
nickel with anions are unlikely. Complexation with organic agents is
poorly understood (U.S. Environmental Protection Agency [EPA] 1986).
Water hardness is the dominant factor governing nickel effects on biota
(Stokes 1988).
Tin is only very slightly soluble at pH values from 4 to 11, as
found in natural settings. Tin occurs naturally in soils at 2 to 200
mg/g (parts per thousand or ppt) with areas of enrichment at
concentrations up to 1,000 mg/g (WHO 1980). In general, however, soil
concentrations in the United States are between 1 and 5 parts per
million (p/m) (Kabata-Pendias and Pendias 1984).
Possible Environmental Concentrations for Metals in the Four Shot Types
in Terrestrial Systems
Calculation of the estimated environmental concentration (EEC) of a
candidate shot in a terrestrial ecosystem is based on 69,000 shot per
hectare (50 CFR 20.134). These calculations assume that the shot
dissolves promptly and completely after deposition.
TICN Alloys
The maximum EEC for TICN shot for tungsten in soil is 21.3 p/m.
This is below the EEC for several other tungsten-based shot types that
we have previously approved. We are not aware of any problems
associated with those shot types. The U.S. EPA does not have a
biosolids application limit for tungsten.
For TICN shot, if the shot are completely dissolved in dry, porous
soil, the maximum EEC for iron is 7.40 p/m. Iron is naturally
widespread, comprising approximately 2 percent of the composition of
soils and sediments in the United States. The EEC for iron from TICN
shot is much lower than that level.
For copper in TICN shot, the maximum EEC in soils is 3.36 p/m. In
comparison, the ceiling concentration limit for biosolids application
for copper is 4,300 p/m (EPA 2000).
The maximum EEC for nickel in TICN shot in soils is 1.62 p/m. This
concentration is a small fraction of the EPA biosolids application
limit of 420 p/m (EPA 2000).
If TICN shot is coated with tin, the EEC for tin in dry soils is
1.31 p/m. There is no EPA biosolids application limit for tin, but it
occurs naturally in soils at 2 to 200 p/m, with areas of enrichment at
concentrations up to 1,000 p/m (WHO 1980). In general, soil
concentrations in the United States are between 1 and 5 p/m; the
suggested maximum concentration in surface soil tolerated by plants is
50 p/m dry weight (Kabata-Pendias and Pendias 1984).
ITN Alloys
The terrestrial EECs for the iron and tungsten from any ITN alloy
(table 2) are below those from approved shot types, and we do not
believe they are a problem in soils. Though data on iron concentrations
in biosolids are unavailable, natural soil background concentrations
range from 5,000 to 50,000 p/m. This is equivalent to 32,500 to 325,000
kg per hectare (kg/h). We do not believe that the worst-case additional
8.01 kg of iron per hectare (about 0.025 percent of natural background
concentrations) would have any effect on plants or animals, especially
since the iron in the shot is not in a soluble form.
[[Page 49544]]
Table 2.--Expected Terrestrial Environmental Concentrations of the Metals in ITN Alloys
--------------------------------------------------------------------------------------------------------------------------------------------------------
Deposition (kg) Terrestrial EEC (p/m)
Alloy (% I/T/N) Shot weight -----------------------------------------------------------------------------
(kg) Iron Tungsten Nickel Iron Tungsten Nickel
--------------------------------------------------------------------------------------------------------------------------------------------------------
1 (70/20/10)................................................. 11.446 8.01 2.29 1.15 12.33 3.52 1.76
2 (40/20/40)................................................. 11.706 4.68 2.34 4.68 7.20 3.60 7.20
3 (44/33/23)................................................. 12.746 5.61 4.21 2.93 8.63 6.47 4.51
4 (10/50/40)................................................. 14.700 1.47 7.35 5.88 2.26 11.31 9.05
5 (20/70/10)................................................. 17.299 3.46 12.11 1.73 5.32 18.63 2.66
6 (10/70/20)................................................. 17.624 1.76 12.34 3.52 2.71 18.98 5.42
--------------------------------------------------------------------------------------------------------------------------------------------------------
Data from biosolid studies indicate that tungsten generally is
present at 40 to 180 p/m, about four times the worst EEC for tungsten
from ITN shot. Therefore, it is unlikely that tungsten from the shot
would exceed concentrations obtained from biosolid applications.
The estimated soil concentration (p/m soil) of nickel for ITN alloy
4 (the highest in nickel) is a very small fraction of the 420 p/m
maximum concentration allowed for terrestrial application of biosolids
and is two orders of magnitude less than the maximum cumulative loading
rate for nickel of 420 kg/h per year (https://www.epa.gov/cgi-bin/
claritgw). We do not believe that nickel from ITN shot would pose an
environmental problem in soils.
TB Shot
Based on the maximum concentration of each metal in any formulation
of TB shot, the increased concentrations in soils for the metals are
14.4 p/m for tungsten, 8.43 p/m for copper, 0.94 p/m for tin, and 0.24
p/m for iron. The EEC for tungsten is lower than the value for ITN
shot, and considerably lower than the values for previously approved
shot types. As noted earlier, the ceiling concentration limit for
biosolids application for copper is 4,300 p/m (EPA 2000). The EEC for
iron from TB shot is extremely small.
TTI Shot
The EEC for tungsten in TTI shot in soil (the increase in soil
concentration) is 12.77 mg/kg or p/m. This is below the EEC for several
other tungsten-based shot types that we have previously approved. We
are not aware of any problems associated with those shot types. The EPA
does not have a biosolids application limit for tungsten. Data from
biosolid studies indicate that tungsten generally is present at 40 to
180 p/m, about four times the worst EEC for tungsten from ITN shot.
Therefore, it is unlikely that tungsten from the shot would exceed
concentrations obtained from biosolid applications.
The EEC for tin in dry soils is 8.37 p/m. In general, soil
concentrations in the United States are between 1 and 5 p/m; the
suggested maximum concentration in surface soil tolerated by plants is
50 p/m dry weight (Kabata-Pendias and Pendias 1984), about six times
the worst-case concentration to be expected from TTI shot.
If the shot are completely dissolved in dry, porous soil, the
maximum EEC for iron is 0.88 p/m. Iron is naturally widespread,
comprising approximately 2 percent of the composition of soils and
sediments in the United States. The EEC for iron from TTI shot is much
lower than that level.
Though data on iron concentrations in biosolids are unavailable,
natural soil background concentrations range from 5,000 to 50,000 p/m.
This is equivalent to 32,500 to 325,000 kg per hectare. We do not
believe that the extremely small addition of the insoluble iron from
TTI shot would have any effect on plants or animals, especially because
the iron in the shot is not in a soluble form.
Possible Environmental Concentrations for Metals in the Four Shot Types
in Aquatic Systems
The EEC for water assumes that 69,000 number 4 shot are completely
dissolved in 1 hectare of water 1 foot (ft) (30.48 cm) deep. The
submitter then calculates the concentration of each metal in the shot
if the shot pellets dissolve completely. For our analyses, we assume
complete dissolution of the shot type containing the highest proportion
of each metal in the range of alloys submitted.
TICN Alloys
For TICN shot, the EEC for tungsten is 4.541 milligrams per liter
(mg/l). The EPA has set no acute or chronic criteria for tungsten in
aquatic systems.
The EEC for iron from TICN shot in water is 1.579 mg/l. The chronic
water quality criterion for iron in fresh water is 1 mg/l (EPA 1986).
EPA has no criterion for salt water.
For copper, the aquatic EEC is 0.717 mg/l. This value is above both
the acute and chronic criteria for freshwater and saltwater. This issue
is discussed in the ``In Vitro Solubility Evaluation of TICN Shot''
section.
The aquatic EEC for nickel from TICN shot is 0.346 mg/l. The EPA
(1986) acute criterion for nickel in fresh water is 1,400 micrograms
per liter ([mu]g/l); the chronic criterion is 160 [mu]g/l. The acute
and chronic criteria for salt water are 75 and 8.3 [mu]g/l,
respectively. Based on the EEC, the maximum release of nickel from TICN
shot would be well below the fresh water acute criterion for protection
of aquatic life.
For the tin in TICN shot, the aquatic EEC is 0.280 mg/l. The lowest
published standard for tin in water is the 4 mg/l water quality
standard for the state of Minnesota. Even in the worst case, the tin
concentration from dissolved TICN shot would be well below this
standard.
ITN Alloys
The aquatic EECs for the metals in ITN shot are shown in table 3.
The EEC for nickel exceeds aquatic water quality criteria (table 4).
However, corrosion studies demonstrated that corrosion rates for all
types of ITN shot are relatively low in both fresh water and seawater.
This corrosion is discussed under ``In Vitro Solubility Evaluation of
ITN Shot.''
[[Page 49545]]
Table 3.--Expected Aquatic Environmental Concentrations of the Metals in ITN Alloys
--------------------------------------------------------------------------------------------------------------------------------------------------------
Deposition (kg) Aquatic EEC (p/m)
Alloy (% I/T/N) Shot weight -----------------------------------------------------------------------------
(kg) Iron Tungsten Nickel Iron Tungsten Nickel
--------------------------------------------------------------------------------------------------------------------------------------------------------
1 (70/20/10)................................................. 11.446 8.01 2.29 1.15 2,629 751 376
2 (40/20/40)................................................. 11.706 4.68 2.34 4.68 1,536 768 1,536
3 (44/33/23)................................................. 12.746 5.61 4.21 2.93 1,840 1,380 962
4 (10/50/40)................................................. 14.700 1.47 7.35 5.88 482 2,411 1,929
5 (20/70/10)................................................. 17.299 3.46 12.11 1.73 1,135 3,973 568
6 (10/70/20)................................................. 17.624 1.76 12.34 3.52 578 4,048 1,156
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table 4.--Aquatic Life Criteria and Worst-Case Concentrations of Metals in ITN Shot
----------------------------------------------------------------------------------------------------------------
Acute water quality Chronic water quality
Metal criterion for aquatic criterion for aquatic Maximum EEC from ITN alloys
life ([mu]g/l) life ([mu]g/l)
----------------------------------------------------------------------------------------------------------------
Iron.............................. No Criterion......... 1,000................ 2,629 (Alloy 1).
Tungsten.......................... No Criterion......... No Criterion......... 4,048 (Alloy 6).
Nickel (fresh water).............. 1,400................ 160.................. 1,929 (Alloy 4).
Nickel (salt water)............... 75................... 8.3.................. 1,929 (Alloy 4).
----------------------------------------------------------------------------------------------------------------
TB Shot
The aquatic EECs for metals in TB shot are shown in table 5. The
EEC for copper is considerably above the criteria for protection of
fresh water and salt water life. However, a solubility study for this
shot type demonstrated that corrosion of TB shot is low. This is
discussed under ``In Vitro Solubility Evaluation of TB Shot.''
Table 5.--Aquatic Life Criteria and Concentrations of Metals in TB Shot
----------------------------------------------------------------------------------------------------------------
Acute water quality Chronic water quality
Metal criterion for aquatic life criterion for aquatic life Maximum EEC
([mu]g/l) ([mu]g/l) from TB shot
----------------------------------------------------------------------------------------------------------------
Tungsten................................ No Criterion.............. No Criterion.............. 3,073
Copper (Fresh Water).................... 13.0...................... 9.0....................... 1,797
Copper (Salt Water)..................... 4.8....................... 3.1....................... 1,797
Tin..................................... 4,0001 \1\................ No Criterion.............. 199.7
Iron.................................... No Criterion.............. 1,000..................... 51.2
----------------------------------------------------------------------------------------------------------------
\1\ Minnesota water quality standard, no federal standard for comparison.
TTI Shot
The EEC for tungsten is 2.72 milligrams per liter (mg/1). The EPA
has set no acute or chronic criteria for tungsten in aquatic systems.
The aquatic EEC for tin is 1.78 mg/1. The lowest published standard
for tin in water is the 4 mg/1 water quality standard for the state of
Minnesota. Tin concentration from dissolved TTI shot would be well
below this standard.
The EEC for iron from TTI shot in water is 0.19 mg/1. The chronic
water quality criterion for iron in fresh water is 1 mg/1 (EPA 1986).
EPA has no criterion for salt water.
In Vitro Solubility Evaluation of TICN Shot
When nontoxic shot is ingested by waterfowl, both physical breakup
of the shot, and dissolution of the metals that comprise the shot, may
occur in the highly acidic environment of the gizzard. In addition to
the standard Tier 1 application information, Spherical Precision
provided the results of an in vitro gizzard simulation test conducted
to quantify the release of metals in solution under the prevailing pH
conditions of the avian gizzard. The metal concentrations released
during the simulation test were, in turn, compared to known levels of
metals that cause toxicity in waterfowl. The evaluation followed the
methodology of Kimball and Munir (1971) as closely as possible. The
average amount of copper and nickel released from eight TICN shot per
day are 1.87 mg and 1.77 mg, respectively.
The maximum tolerable level of dietary copper during the long-term
growth of chickens (Gallus domesticus) and turkeys (Meleagris species)
has been reported to be 300 p/b (Committee on Mineral Toxicity in
Animals (CMTA) 1980). At the maximum tolerable level for chronic
exposure of 300 ppb for poultry, a 1.8 kg chicken consuming 100 g of
food per day (Morck and Austic 1981) would consume 30 mg copper per day
(16.7 mg of copper per kg of body weight per day). The average amount
of copper released from eight TICN shot is 1.87 mg per day, which is
well below concentrations that cause copper toxicosis in waterfowl. A
bird would have to ingest 129 TICN shot to exceed the maximum tolerable
level.
No reproductive or other effects were observed in mallards that
consumed the equivalent of 102 mg of nickel as nickel sulfate each day
for 90 days (Eastin and O'Shea 1981). Therefore, the average amount of
nickel released from eight TICN shot/day of 1.77 mg will pose no risk
of adverse effects to waterfowl. Additionally, metallic nickel likely
has a lower absorption from the gastrointestinal tract than does the
nickel sulfate used in the mallard reproduction study, further
decreasing the absorbed dose of TICN shot compared to the published
toxicity study described above.
We concluded that TICN shot is very resistant to degradation, and
that it poses no risk to waterfowl if ingested in the field. The slow
breakdown rate of
[[Page 49546]]
1.53 mg per shot per day only permits the release of 0.233 mg of copper
and 0.221 mg of nickel per shot per day, both of which are
concentrations that are orders of magnitude below toxic levels of
concern for copper and nickel in waterfowl.
In Vitro Solubility Evaluation of ITN Shot
Fresh water, seawater, and an ``artificial gizzard'' environment
(Kimball and Munir, 1971) were evaluated to determine their corrosion
rates on each of the six alloys, plus steel as a standard. The
``artificial gizzard'' test, although developed for lead alloy
evaluation, proved to reliably simulate the mallard gizzard for both
steel and ITN alloys and constitutes a very conservative approach for
evaluation of nontoxic shot. This test resulted in corrosion/erosion
rates up to twice those measured in steel and Tungsten-Nickel-Iron
mallard in-vivo studies (January 4, 2001, 66 FR 737).
The ITN alloys with relatively low concentrations of tungsten and
nickel corrode in a manner similar to that of steels. Corrosion rates
of such steels are roughly linear over a wide range of exposure time.
This corrosion is in contrast with that of alloys such as stainless
steel, tungsten-nickel iron, or ``high-alloy'' varieties of ITN, which
readily form passivating oxide layers that impede further corrosion.
Assuming that the short-term rate of shot weight loss would continue
for one month in a static aqueous environment (a conservative
assumption, because natural fresh water and seawater environments are
dynamic, and because corrosion products forming on metal surfaces tend
to progressively retard corrosion rates), the actual EECs are presented
in table 6. These data show that the nickel concentration from ITN shot
actually will be well below both the acute and chronic criteria for
nickel in aquatic settings.
Table 6.--Environmental Concentrations of Metals in ITN Shot Based on Solubility Testing
----------------------------------------------------------------------------------------------------------------
Fresh Water EEC ([mu]g/l) Salt Water EEC ([mu]g/l)
Alloy (% I/T/N) -----------------------------------------------------------------
Iron Tungsten Nickel Iron Tungsten Nickel
----------------------------------------------------------------------------------------------------------------
1 (70/20/10).................................. 27.16 7.76 3.87 3.36 0.97 0.23
2 (40/20/40).................................. 1.95 0.97 1.95 0 0 0
3 (44/33/23).................................. 12.61 9.69 6.70 10.66 7.99 2.60
4 (10/50/40).................................. 1.45 7.27 5.82 0 0 0
5 (20/70/10).................................. 6.79 23.77 3.40 2.72 20.37 2.90
6 (10/70/20).................................. 0 0 0 0 0 0
----------------------------------------------------------------------------------------------------------------
ENVIRON-Metal also provided the results of an in-vitro gizzard
simulation test conducted to quantify the release of metals in solution
under the prevailing pH conditions of the avian gizzard (table 7).
These data also demonstrate that the hazards from these alloys to
wildlife would be very minimal.
Table 7.--Metal Loss From ITN Alloys in a Simulated Gizzard Over a 14-Day Period.
----------------------------------------------------------------------------------------------------------------
Initial Weight Loss (mg)
weight of --------------------------------------- Percent
Alloy (% I/T/N) 10 number weight loss
4 shot (g) Iron Tungsten Nickel
----------------------------------------------------------------------------------------------------------------
1 (70/20/10)................................... 1.994 179.90 51.40 25.70 12.9
2 (40/20/40)................................... 2.687 64.00 32.00 64.00 5.9
3 (44/33/23)................................... 2.766 72.60 54.45 37.95 5.9
4 (10/50/40)................................... 3.479 13.10 65.50 52.40 3.7
5 (20/70/10)................................... 3.462 18.80 65.80 9.40 2.7
6 (10/70/20)................................... 3.418 19.40 135.80 38.8 5.7
----------------------------------------------------------------------------------------------------------------
In Vitro Solubility Evaluation of TB Shot
The EEC for copper EEC was over 138 times the freshwater acute
criterion of 13 g/l, and 200 times the freshwater chronic criterion of
9.0 g/l. However, Olin noted that the very conservative assumptions
used to calculate the copper EEC are only an indication of the likely
effect of deposition of TB shot in an aquatic setting. Therefore, as an
addendum to the application for TB shot, Olin had an in-vitro
dissolution test in water conducted. The test was conducted to quantify
the release of metals from TB shot at pH values of 5.6, 6.6, and 7.6 in
synthetic buffered waters. The highest EEC for copper from the
dissolution evaluations was 0.15 [mu]g/l at pH 5.6. The hardness-
adjusted chronic water quality criterion for copper was 9.7 [mu]g/l,
approximately 65 times the worst-case EEC. Therefore, detrimental
effects in aquatic systems from dissolution of TB shot would be highly
unlikely.
Olin provided the results of an in-vitro gizzard simulation test
conducted to quantify the release of metals in solution under the
prevailing pH conditions of the avian gizzard. The simulation test
demonstrated that a number 4 TB shot would release about 0.67 mg of the
alloy per day. This, in turn, would mean release of approximately 0.24
mg of copper per day.
Olin pointed out that the theoretical availability of copper from
this in-vitro gizzard simulation test should be considered maximal when
compared to the Irby et al. (1967) study results or the CMTA (1980)
guideline. Unlike the in-vivo gizzard, which resembles an open
corrosion system in which the products of the corrosion process are
constantly being eliminated (Kimball and Munir 1971), the test design
for this in-vitro gizzard simulation was a closed corrosion system.
Therefore, fine pieces of shot that would be released, and normally
discarded from the gizzard, remained in the dissolution medium and
potentially yielded more copper. Additionally, the analytical samples
were analyzed for total metals with no
[[Page 49547]]
filtration or centrifugation prior to analysis. As a result, the fine
pieces of shot that were not fully dissolved and would normally be
excreted were included in the total copper concentrations reported.
Summary: Solubility Evaluations
We have previously approved as nontoxic other shot types that
contain tungsten, iron, and tin. Previous assessments of nontoxic shot
types indicated that the potential release of iron, tungsten, or tin
from TICN, ITN, or TB shot should not harm aquatic or terrestrial
systems and we believe the small amount of tin in TB shot is not likely
to harm waterfowl. The solubility testing further indicates that the
release of nickel from ITN shot and copper from TICN or TB shot is not
sufficient to present a hazard to aquatic systems or to biota. We
propose to approve the four shot types as nontoxic. Our approval is
based on the toxicological report, acute toxicity studies,
reproductive/chronic toxicity studies, and other published research.
The available information indicates that the four shot types are
nontoxic when ingested by waterfowl and that they pose no significant
danger to migratory birds, other wildlife, or their habitats.
Impacts of Approval of the Four Shot Types
Effects of the Metals
Iron
Iron is an essential nutrient. Iron toxicosis in mammals is
primarily a phenomenon of overdosing of livestock. Maximum recommended
dietary levels of iron range from 500 p/m for sheep to 3000 p/m for
pigs (National Research Council [NRC] 1980). The amount of iron in any
of the four shot types would not pose a hazard to mammals.
Chickens require at least 55 p/m iron in the diet (Morck and Austic
1981). There were no ill effects on chickens fed 1,600 p/m iron in an
adequate diet (McGhee et al. 1965), and chicks tolerated 1,600 p/m iron
in the diets that included adequate copper, although decreased weight
gains and increased mortality were observed in copper-deficient diets
(McGhee et al. 1965). At the maximum tolerable level for chronic
exposure of 1,000 p/m for poultry (NRC 1980), a 1.8 kg chicken
consuming 100 grams of food per day (Morck and Austic 1981) would
consume 100 mg iron per day (56 mg per kg of body weight per day).
Deobald and Elvehjem (1935) reported that 4,500 p/m iron in the
diet produced rickets in chicks. Adverse effects were not observed when
turkey poults were fed diets amended with 440 p/m iron (Woerpel and
Balloun 1964).
Turkey poults fed 440 p/m in the diet suffered no adverse effects.
The tests, in which eight number 4 tungsten-iron shot were administered
to each mallard in a toxicity study indicated that the 45 percent iron
content of the shot had no adverse effects on the test animals (Kelly
et al. 1998).
We are not aware of acute toxicity data for iron in waterfowl.
Zinc-coated iron shot appeared to have little or no effect on ducks
dosed with eight number 6 shot; mortality and weight loss for treated
ducks were comparable to those for control animals (Irby et al. 1967).
Game-farm mallards administered eight number 4 pellets of tungsten-
iron shot, indicated no adverse effects from either the tungsten or the
iron (Kelly et al. 1998). This shot formulation has a much greater iron
content (45 percent) than do the shot types considered here.
Tungsten
Tungsten salts are toxic to mammals. Lifetime exposure to 5 p/m
tungsten as sodium tungstate in drinking water produced no discernible
adverse effects in rats (Rattus species) (Schroeder and Mitchener
1975). However, with 100 p/m tungsten as sodium tungstate in drinking
water, rats had decreased enzyme activity after 21 days (Cohen et al.
1973).
Tungsten may be substituted for molybdenum in enzymes in mammals.
Ingested tungsten salts reduce growth, and can cause diarrhea, coma,
and death in mammals (e.g. Bursian et al. 1996, Cohen et al. 1973,
Karantassis 1924, Kinard and Van de Erve 1941, National Research
Council 1980, Pham-Huu-Chanh 1965), but elemental tungsten is virtually
insoluble and therefore essentially nontoxic. Tungsten powder added to
the food of young rats at 2, 5, and 10 percent by mass for 70 days did
not affect health or growth (Sax and Lewis 1989). A dietary
concentration of 94 p/m did not reduce weight gain in growing rats (Wei
et al. 1987). Exposure to pure tungsten through oral, inhalation, or
dermal pathways is not reported to cause any health effects (Sittig
1991).
Acute tungsten toxicosis results in death from respiratory
paralysis, often preceded by diarrhea and coma. Chronic intoxication is
most evident in reduced growth rates. However, the most sensitive sign
is reduced xanthine oxidase activity. Xanthine oxidase is an enzyme
that is dependent upon molybdenum for proper functioning. It is thought
that tungsten readily substitutes for molybdenum, with subsequent
reduction in enzyme activity; supplemental dietary molybdenum will
reverse the symptoms. The National Research Council Committee on Animal
Nutrition recommends a maximum tolerable dose of 20 p/m tungsten in the
diet for effective rearing of livestock (NRC 1980).
The LD50 of tungsten as sodium tungstate
(Na2WO4) administered by intraperitoneal
injection is 112 p/b body weight in male rats and 79 p/b body weight in
mice (Mus species) (Pham-Huu-Chanh 1965). This would classify tungsten
as ``very toxic'' when administered intraperitoneally as a soluble
salt. Kinard and Van de Erve (1941) showed that
Na2WO4 is the most toxic tungsten salt, when
compared with tungsten oxide and ammonium paratungstate.
Tungsten administered in the diet had no effects on rats until
reaching 150 p/m diet when carcinoma incidence was increased in female
Sprague-Dawley rats (Wei et al. 1987). Higgins et al. (1956a, b) noted
that dietary concentrations of 45 or 94 p/m tungsten produced no
adverse effects on weight gain in growing rats. Other studies with rats
indicate that dietary exposure to 5,000 p/m tungsten oxide
(WO3) or Na2WO4 results in 90 percent
and 80 percent mortality, respectively, by the 70th day of exposure
(NRC 1980). However, lifetime exposure of rats to 5 p/m tungsten as
Na2WO4 in drinking water resulted in no
observable adverse effects (Schroeder and Michener 1975). At 100 p/m
tungsten as Na2WO4 in drinking water, rats had
decreased enzyme activity after 21 days of exposure (Cohen et al.
1973).
Goats (Capra hircus) appear to be less tolerant of dietary
tungsten. A 5-month exposure to 22.5 p/m dietary tungsten as
Na2WO4 resulted in depressed liver xanthine
oxidase activity in growing kids. Milk production in goats and cows
(Bos species) was unaffected by a single oral exposure to 25.0 p/b body
weight of Na2WO4 (Owen and Proudfoot 1968). Anke
and Groppel (1985) established that goats require at least 0.06 p/m
tungsten in their diets for optimal reproduction.
Chickens given a complete diet showed no adverse effects of 250 p/m
sodium tungstate administered for 10 days in the diet. However, 500 p/m
in the diet reduced xanthine oxidase activity and reduced growth of
day-old chicks (Teekell and Watts 1959). Adult hens had reduced egg
production and egg weight on a diet containing 1,000 p/m tungsten (Nell
et al. 1981). Ecological Planning and Toxicology (1999) concluded that
the No Observed
[[Page 49548]]
Adverse Effect Level for tungsten for chickens should be 250 p/m in the
diet; the Lowest Observed Adverse Effect Level should be 500 p/m. Kelly
et al. (1998) demonstrated no adverse effects on mallards dosed with
tungsten-iron or tungsten-polymer shot according to nontoxic shot test
protocols.
Breeder hen exposure to 250 p/m tungsten as sodium tungstate for 10
days had no adverse effects, but increasing the diet to 500 p/m
tungsten for an additional 20 days resulted in decreased xanthine
oxidase activity (Teekell and Watts 1959). Similarly, day-old chicks on
a 500 p/m tungsten diet with adequate molybdenum showed reduced rate of
gain (Selle 1942).
Nell et al. (1981) fed laying hens diets containing 1,000 p/m
tungsten (unspecified salt) for five months; control diets contained
0.4 p/m tungsten. Hens were artificially inseminated and eggs were
collected and set weekly. Three of 40 hens on the high-tungsten diet
died, and the remaining 37 had reduced egg production and egg weight.
Egg fertility and hatchability were not affected. Liver tungsten was
significantly elevated in treated birds, although there was no effect
on body weight.
Day-old white leghorn chickens placed on a molybdenum-deficient
diet for 35 days showed a decreased rate of growth and increased
mortality at 45 p/m tungsten as sodium tungstate (Higgins et al. 1956a,
b). However, this is not an accurate reflection of tungsten toxicity
because low molybdenum levels potentiate the effects of tungsten (NRC
1980).
Ecological Planning and Toxicology (1999) concluded that the No
Observed Adverse Effect Level (NOAEL) for tungsten for chickens should
be 250 p/m in the diet; the Lowest Observed Adverse Effect Level should
be 500 p/m. An adult chicken fed a diet of 1,000 p/m tungsten for 150
days would ingest about 100 mg of tungsten per day, or a total of 15
grams. In the USFWS guidelines for a reproduction study for shot,
mallards would receive eight number 4 shot on four dosing periods. A
total of 32 TICN shot during the course of the study, each containing
0.2006 grams of tungsten, would result in a total exposure of 6.42
grams of tungsten, if the tungsten in the shot is totally dissolved.
This estimated exposure of 6.42 grams of tungsten during a TICN shot
mallard reproductive study is about 43 percent of the 15 grams
demonstrated to cause reproductive effects in chickens.
The effects of ingestion of tungsten by mallards as elemental metal
in a shot pellet were studied by Ringelman et al. (1993). Birds were
given pellets of 39 percent tungsten, 44.5 percent bismuth, and 16.5
percent tin by weight, per bird. No evidence of toxicity or other
histological changes were reported. Tungsten was not detected in liver
or kidney tissue.
Dosing mallards with eight number 4 Iron-Tungsten shot (with 55
percent tungsten) also produced no tungsten toxicity in the ducks
(Kelly et al. 1998). In that study, birds received eight number 4
pellets by oral gavage and were observed for changes in serum enzymes,
organ weights, histology of tissues and accumulation of metals in bone.
Tungsten was detected in femur, liver, and kidneys of dosed ducks, but
no other significant changes were measured. Iron-Tungsten shot eroded
by 55 percent and Tungsten-Polymer shot eroded by 80 percent over the
course of the study; however, tissue concentrations were lower in the
Tungsten-Polymer birds than in the Iron-Tungsten group. The shot were
55 percent tungsten for the Iron-Tungsten formulation and 95.5 percent
tungsten for the polymerized shot. The amount of tungsten in TICN shot
(40-76 percent) is similar to that in the Iron-Tungsten shot (55
percent). Tungsten-Nickel-Iron shot in the study by Ecotoxicology &
Biosystems Associates, Inc. (2000), conducted with a proportion of
tungsten similar to that in TICN shot, was not toxic.
Kraabel et al. (1996) surgically embedded tungsten-bismuth-tin shot
in the pectoralis muscles of ducks to simulate wounding by gunfire and
to test for toxic effects of the shot. The shot produced no toxic
effects nor induced adverse systemic effects during the 8-week study.
Copper
Copper is a dietary essential for all living organisms. In most
mammals, ingestion of one TICN shot pellet would result in release of 8
to 25 mg of copper, not all of which would be absorbed. In humans,
ingestion of a pellet could mobilize approximately 8 mg of copper.
These low levels of copper would not pose any risk to mammals.
Copper requirements in birds may vary depending on intake and
storage of other minerals (Underwood 1971). The maximum tolerable level
of dietary copper during the long-term growth of chickens and turkeys
is 300 p/m (CMTA 1980). Eight-day-old ducklings were fed a diet
supplemented with 100 p/m copper as copper sulfate for eight weeks.
They showed greater growth than controls, but some thinning of the
caecal walls (King 1975). Studying day-old chicks, Poupoulis and Jensen
(1976) reported that no gizzard lining erosion could be detected in
chicks fed 125 p/m of copper for four weeks, but they detected slight
gizzard erosion in chicks fed 250 p/m copper. The authors found that it
required 500 to 1,000 p/m of copper to depress growth and weight gain
of chicks. Jensen et al. (1991) found that 169 p/m copper in the diet
produced maximal weight gain in chickens.
Stevenson and Jackson (1979) studied the influence of dietary
copper addition on the body mass and reproduction of mature domestic
chickens. Hens fed on a diet containing 250 p/m copper for 48 days
showed a similar rate of food intake as control hens that had no copper
in their diet. Additionally, the mean number of eggs laid daily did not
differ between hens fed 250 p/m copper and the controls. After 4 months
of being fed at dietary copper levels in excess of 500 p/m, negative
effects on the daily food intake, body mass loss, and egg-laying rates
were observed.
At the 300 p/m level for chronic exposure for poultry, a 1.8 kg
chicken consuming 100 g of food per day (Morck and Austic 1981) would
consume 30 mg of copper per day (16.7 mg of copper per kg of body
weight/day). One number 4 TICN shot contains a maximum of 31.7 mg of
copper. However, at the 0.233 mg of copper per shot per day release
rate from the solubility testing, a bird would have to ingest at least
128 TICN shot to exceed the maximum tolerable level. Thus, the copper
release from the TICN shot appears to be well below the level that
could cause copper toxicosis in waterfowl. The average amount of copper
released from 8 TB nontoxic shot per day is 7.87 mg, so a bird would
have to ingest over 30 shot to exceed the maximum tolerable level.
Day-old poults fed diets containing 500 p/m ration for 24 weeks
showed reduced growth and increased gizzard histopathology (Kashani et
al. 1986). Growing domestic turkeys showed no long-term effects when
fed 300 p/m copper in the daily diet, but 800 p/m of copper in the diet
for 3 weeks inhibited growth with no adverse effects on survival
(Supplee 1964). No effect of feeding 400 p/m of copper as copper
sulfate to turkey poults in the daily diet for 21 weeks was reported,
and it was concluded that poults could tolerate 676 p/m of copper
without deleterious effects. Growth was reduced in poults fed 800 p/m
and 910 p/m of copper over the same time (Vohra and Kratzer 1968).
Their conclusion was supported by another study that found that copper
in the diet of domestic turkeys had to rise to 500 to 750 p/m level
before signs of slight toxicity appeared, assuming that
[[Page 49549]]
adequate methionine also was present (Christmas and Harms 1979).
Henderson and Winterfield (1975) reported acute copper toxicity in
3-week-old Canada geese (Branta canadensis) that had ingested water
contaminated with copper sulfate. The authors calculated the copper
intake to be about 600 mg copper sulfate/kg body weight, or 239 mg
copper/kg. The amount of copper released from eight number 4 shot would
be 42.26 mg, which is much less that the 239 p/b toxic level.
Irby et al. (1967) dosed 24 Mallard ducks with 8 number 6 pure
copper shot to observe if they were toxic over a 60-day exposure
period. They calculated that the total mass of copper in the gizzard
was 0.6 gram, and observed that none of the ducks died from copper
toxicosis after 60 days. TB shot is 35.1 percent copper by weight, so
eight shot would contain 0.64 grams of copper.
International Nontoxic Composites, Inc. (2003) reported that pure
copper control shot breaks down at the rate of 18.42 mg copper per gram
of shot per day, or 11.05 mg copper per day for 0.6 grams of copper
shot, under in vitro gizzard simulation test conditions. However, TB
shot releases only 4.35 mg copper per gram of shot per day or 7.87 mg
of copper per day for 1.81 grams of shot under the same test
conditions. This indicates that TB shot should not be a hazard for
wildlife that consume it.
The EPA (2002) provided both acute and chronic freshwater quality
criteria for copper, which are functions of water hardness. The
freshwater acute criterion for a water body with hardness of 100 mg/l,
for example, is 13 [mu]g/l, and the chronic criterion is 9.0 [mu]g
copper per liter. The EPA acute and chronic saltwater quality criteria
are not affected by hardness, and are 4.8 and 3.1 [mu]g/l.
Nickel
Deficiencies have been reported in diets ranging from 2 to 40
billion p/b nickel (NRC 1980). The dietary requirement for nickel has
been set at 50 to 80 p/b for the rat and chick (Nielsen and Sandstead
1974). Humans consume up to 900 [mu]g per day as a normal dietary
intake (Nieboer et al. 1988). Though it is necessary for some enzymes,
nickel competes with zinc, calcium, and magnesium for binding sites on
most of the metal-dependent enzymes, resulting in various levels of
inactivation, although it is essential for functioning of some enzymes,
particularly urease (Andrews et al. 1988, Nieboer et al. 1988). Water-
soluble nickel salts are poorly absorbed from the gastrointestinal
tract, averaging only 3 percent to 6 percent assimilation efficiency in
rats (Nieboer et al. 1988).
Rats fed nickel carbonate concentrations up to 1,000 p/m for 3 to 4
months did not show treatment-related effects, nor was body weight of
pups affected (Phatak and Patwardhan 1950). Elevated nickel
concentrations in pups were observed in the 500 and 1,000 p/m treatment
groups. Young rats were fed nickel catalyst (finely divided nickel
suspended in vegetable oil and supported on kieselguhr) at 250 p/m for
16 months with no effects (Phatak and Patwardhan 1952).
Rats fed 1,000 p/m nickel sulfate for 2 years exhibited mild
effects, such as reduced body weight and liver weight, but increased
heart weight (Ambrose et al. 1976). Also, there was an increase in the
number of stillborn pups and a decrease in weanling weights through
three generations. Nickel chloride was most toxic to rats. Young rats
decreased food consumption and lost body weight within 13 days in diets
containing 1,000 p/m nickel as nickel chloride (Schnegg and
Kirchgessner 1976).
Calves showed weight loss and decreased feed intake, organ size,
and nitrogen retention when fed 1,000 p/m nickel and nickel carbonate
for 8 weeks (O'Dell et al. 1970a, 1971). Calves fed 250 p/m nickel did
not show effects. Lactating dairy cows were not affected by 50 or 250
p/m dietary nickel (Archibald 1949, O'Dell et al. 1970b). Soluble
nickel salts are very toxic to mammals, with an oral LD50 of 136 p/b in
mice, and 350 p/b in rats (Fairchild et al. 1977). Nickel catalyst
(finely divided nickel in vegetable oil) fed to young rats at 250 p/m
for 16 months, however, produced no detrimental effects (Phatak and
Patwardhan 1952).
Water-soluble nickel salts are poorly absorbed if ingested by rats
(Nieboer et al. 1988). Nickel carbonate caused no treatment effects in
rats fed 1,000 p/m for 3 to 4 months (Phatak and Patwardhan 1952). Rats
fed 1,000 p/m nickel sulfate for 2 years showed reduced body and liver
weights, an increase in the number of stillborn pups, and decrease in
weanling weights through three generations (Ambrose et al. 1976).
Nickel chloride was even more toxic; 1,000 p/m fed to young rats caused
weight loss in 13 days (Schnegg and Kirchgestiner 1976).
In chicks from hatching to 4 weeks of age, 300 p/m nickel as nickel
carbonate or nickel acetate in the diet produced no observed adverse
effects, but concentrations of 500 p/m or more reduced growth (Weber
and Reid 1968). A diet containing 200 p/m nickel as nickel sulfate had
no observed effects on mallard ducklings from 1 to 90 days of age.
Diets of 800 p/m or more caused significant changes in physical
condition of the ducklings (Cain and Pafford 1981).
Mallard ducklings fed 1,200 p/m nickel as nickel sulfate from 1 to
90 days of age experienced reduced growth rates, tremors, paresis, and
death (71 percent within 60 days) (Cain and Pafford 1981). Weights of
ducklings receiving 200 and 800 p/m nickel were not significantly
different than controls, but the humerus weight/length ratio, a measure
of bone density, was significantly lower than controls among females in
the 800 p/m group and all birds in the 1,200 p/m group. There was no
mortality in the 200 and 800 p/m groups.
Breeding pairs of mallards were fed diets containing 0, 12.5, 50,
200, and 800 p/m nickel as nickel s
