Public Comments and Revised Final Criteria for Removing Chemicals From Future Editions of CDC's National Report on Human Exposure to Environmental Chemicals, 16685-16688 [E8-6350]
Download as PDF
<![CDATA[
Federal Register / Vol. 73, No. 61 / Friday, March 28, 2008 / Notices
participants should submit materials to
the NVPO staff person designated as the
contact for additional information. All
materials should be submitted to the
designated point of contact no later than
close of business April 21, 2008. Preregistration is required for public
comment. Any individual who wishes
to participate in the public comment
session should e-mail
angela.shen@hhs.gov or call 202–690–
5566.
There is limited space available for
the public to attend this meeting.
However, it is desired that the public
participate in the discussions, as well.
Registration is required to attend the
meeting; registration information can be
found at: https://
nvpo.constellagroup.com. Registration
for the meeting will be accepted until
April 5, 2008. Registration after that
date will be on the basis of space
availability. Individuals who plan to
attend and need special assistance, such
as sign language interpretation or other
reasonable accommodations, should
notify the designated contact person.
Dated: March 24, 2008.
Bruce Gellin,
Director, National Vaccine Program Office.
[FR Doc. E8–6433 Filed 3–27–08; 8:45 am]
BILLING CODE 4150–44–P
DEPARTMENT OF HEALTH AND
HUMAN SERVICES
Centers for Disease Control and
Prevention
[ATSDR–241]
Public Comments and Revised Final
Criteria for Removing Chemicals From
Future Editions of CDC’s National
Report on Human Exposure to
Environmental Chemicals
Centers for Disease Control and
Prevention (CDC), Department of Health
and Human Services (HHS).
SUMMARY: On Tuesday, May 16, 2006,
CDC published draft criteria for
removing chemicals from future releases
of CDC’s National Report on Human
Exposure to Environmental Chemicals
(the ‘‘Report’’) (See FR, Vol. 71, No. 94,
p. 28346–7). This and previous notices
related to the ‘‘Report’’ are at https://
www.cdc.gov/exposurereport/
chemical_nominations.htm. The
proposed criteria provided that a
chemical may be removed from the
‘‘Report’’ if (1) a new replacement
chemical (i.e., a metabolite) is more
representative of exposure than is the
chemical currently measured; or (2)
after three survey periods (or not less
sroberts on PROD1PC70 with NOTICES
AGENCY:
VerDate Aug<31>2005
17:57 Mar 27, 2008
Jkt 214001
than 6 years), detection rates for all
chemicals within a methodological and
chemically related group are less than 5
percent for all population subgroups
(i.e., two sexes, three race/ethnicity
groups, and three age groups); or (3)
after three survey periods (or not less
than 6 years), levels of chemicals within
a methodological and chemically related
group are unchanged or declining in all
the specific subgroups as documented
in the ‘‘Report.’’
Using these criteria, CDC would have
continued to measure the chemical and
not remove it from the ‘‘Report’’ if it met
either of two proposed exceptions to
these criteria: (a) It is a chemical for
which there is an established
biomonitoring threshold (e.g., CDC’s
level of concern for blood lead levels in
children) or any chemical for which
there is widespread public health
concern (e.g., mercury) or (b) three
survey periods (or not less than 6 years)
have passed, constituting the minimum
time before a chemical could be
removed; a longer period may be
necessary to account for the half-life of
a particular chemical or to account for
a recent change (e.g., the removal of a
chemical from commerce) that would
necessitate monitoring of the
population. In that notice, CDC pointed
out that the criteria for removing a
chemical from the ‘‘Report’’ are not
corollaries of the criteria for adding
chemicals to the ‘‘Report.’’
Summary of Public Comments
CDC received 31 public comments on
the criteria cited above and describes
below the comments received and
CDC’s responses to those comments.
Comments are grouped in the following
categories: Removal process, criterion 1,
criterion 2, criterion 3, and exceptions
‘‘a’’ and ‘‘b.’’
General Informational Comments
Related to Process and Procedure
CDC received several public
comments about how the process of
removing chemicals from the ‘‘Report’’
would be implemented. These generally
pertained to (1) concurrence on the
scientific basis for exposure assessment;
(2) analytical cost considerations as
secondary; (3) description of the policy
basis for the process; (4) consideration
of and suggestions for alternative
approaches to limited sample volumes;
and (5) affirmation of decision
procedures, transparency, and public
notification.
CDC responses to general
informational comments:
Understanding exposures through
biomonitoring can help scientists focus
research on those chemicals found in
PO 00000
Frm 00065
Fmt 4703
Sfmt 4703
16685
people’s bodies and target the
appropriate levels of exposure. The
‘‘Report’’ provides unique exposure
assessment information and not
assessment of health risk. However, the
biomonitoring data in the ‘‘Report’’ can
facilitate and complement the riskassessment process. For some
chemicals, such as lead and mercury,
risks have become better characterized
when biomonitoring levels have become
the benchmark to which the risks are
tied. CDC considers the public health
utility and quality of biomonitoring
information to be the primary
consideration, with cost of analysis as
an important, but secondary,
consideration (See Federal Register Vol.
67, No. 34 March 20, 2002, pages
12996–7).
The policy basis for the development
of criteria for removing chemicals from
the ‘‘Report’’ was developed in
consideration of sound science and
resource utilization. With guidance from
a Work Group that was convened at the
direction of the Board of Scientific
Counselors of the National Center for
Environmental Health and the Agency
for Toxic Substances and Disease
Registry (NCEH/ATSDR), the proposed
criteria were established, and comments
from the public were solicited through
the Federal Register notice published in
May 2006 (Vol. 71, No. 94, p. 28346–7).
As currently described, only one of
the three criteria needs to apply to delist
a chemical. That is, the three criteria
apply independently—no combinations
of criteria are necessary to qualify a
chemical for removal from the ‘‘Report.’’
When chemicals published in the
‘‘Report’’ meet a criterion for removal,
they will be deleted from future reports.
The Division of Laboratory Sciences
(DLS) at NCEH will make these
decisions using the finalized criteria
only and will post the names of the
removed chemicals on its Web site:
https://www.cdc.gov/exposurereport.
Two commenters provided helpful
suggestions for maintaining flexibility in
applying the removal process and
suggested alternative plans for optimal
use of samples. For those chemicals
requiring large amounts of sample
volume to detect the chemicals,
alternatives such as less frequent
sampling or pooled analyses are
appropriate alternatives. CDC has
actively researched these alternatives
and will continue to weigh the relative
cost-benefit of other approaches in
addressing the issue of limited sample
volume. Such approaches could include
less frequent sampling, pooling of
samples, and development of more
sensitive analytical methods. For
difficult decisions, the NCEH/ATSDR
E:\FR\FM\28MRN1.SGM
28MRN1
sroberts on PROD1PC70 with NOTICES
16686
Federal Register / Vol. 73, No. 61 / Friday, March 28, 2008 / Notices
Board of Scientific Counselors will be
consulted for advice on the use of
alternative approaches.
This process of announcing draft
criteria and requesting comment on the
criteria was the first step in ensuring
transparency. Commenters’ involvement
in this process is evidence of CDC’s
efforts to involve multiple groups with
varied viewpoints. CDC will announce
the process for both nominating and
removing chemicals from the ‘‘Report’’
in a future Federal Register notice.
When chemicals are removed through
this process, announcements will be
made on CDC’s Web site (https://
www.cdc.gov/exposurereport).
Descriptions of ongoing activities
related to the ‘‘Report’’ have been
provided in public meetings with
advisory groups, in regional and
national conferences, through
publication of introductory material in
the ‘‘Report’’ itself, in previous Federal
Register announcements, and in
postings of these materials on the CDC
Web site.
Specific comments related to Criterion
1: If a new replacement chemical (i.e.,
a metabolite) is more representative of
exposure than the chemical currently
being measured.
Two specific comments and one
general comment were received.
CDC Responses related to Criterion 1:
The first comment recommends a
phased overlap in the analysis of the
previously measured chemical with the
replacement chemical. CDC agrees with
this recommendation, which would
occur naturally in the course of the
scientific accrual of knowledge and
measurements about the new
replacement chemical. Both old and
replacement chemicals may exist in the
‘‘Report’’ simultaneously until such
knowledge and experience are accrued.
The second comment requested a
wording change in criterion 1 from
‘‘(i.e., a metabolite)’’ to ‘‘(i.e., a
metabolite or other chemical).’’ The
wording change is accepted.
A general comment was made that the
meaning of the phrase ‘‘is more
representative of exposure’’ can be
inferred. CDC notes that a replacement
chemical is more representative of
exposure when the measured
concentration of the replacement
chemical accounts for a greater fraction
of the dose or has pharmacokinetic
characteristics that decrease the
variability in exposure estimation (such
as longer persistence in the body).
Revised draft Criterion 1: If a new
replacement chemical (i.e., a metabolite
or other chemical) is more
representative of exposure than the
chemical currently being measured.
VerDate Aug<31>2005
17:57 Mar 27, 2008
Jkt 214001
Specific comments related to Criterion
2: If after three survey periods (or not
less than 6 years), detection rates for all
chemicals within a methodologically
and chemically related group are less
than 5 percent for all population
subgroups (e.g., two sexes, three race/
ethnicity groups, and three age groups).
CDC received six overlapping
comments from different commenters
on the description or discussion of the
following: (1) The requirement of a 5%
detection rate for all population
subgroups to meet the criterion; (2) the
adequate number of survey periods
applicable to the criterion; (3) the
definition of ‘‘methodological and
chemically related group’’; and (4) the
application of the criterion to the entire
group versus individual chemicals in
the group to achieve cost savings.
CDC Responses Related to Criterion 2
(1) The requirement of a 5% detection
rate. Not removing a chemical from the
‘‘Report’’ until all reported subgroups
have fallen below the 5% detection rate
is a conservative approach, allowing
continued population monitoring even
though some subgroups would no
longer meet that criterion. A 5%
detection rate allows an estimate of the
95th percentile for a population group.
The 95th percentile is extremely useful
for characterizing levels of unusual
exposure in a population. If removal of
a chemical from the ‘‘Report’’ resulted
by meeting this criterion, but there were
known exposures to special groups that
are of public health interest, targeted
monitoring studies could be
recommended. CDC may be able to
assist some states or other agencies in
biomonitoring of special groups with
unusual potential for exposure or who
potentially may be at more risk for
adverse health effects.
(2) The adequate number of survey
periods applicable to the criterion. No
absolute guide governs the number of
survey periods necessary for inclusion
in this criterion. CDC considered three
survey periods because this number was
the minimum number of survey point
estimates from which trends might be
calculated. Still, environmental
conditions and releases of chemicals
may change human exposures over
time, and for some persistent
chemicals—that is, persistent either in
the body or in the environment—the 6year period would be too short to
measure a meaningful change. Thus, to
accommodate these situations, CDC
added exemption ‘‘b.’’ CDC has also
rephrased the following statement to
address reassessment of a chemical
removed from the ‘‘Report’’ under either
criterion 2 or 3: ‘‘For a chemical that
PO 00000
Frm 00066
Fmt 4703
Sfmt 4703
meets criterion 2 or 3, the chemical
would be removed from the ‘Report’ for
two future survey periods (4 years) and
then measured again in the following
survey period (2 years). If either
criterion 2 or 3 is still satisfied for this
12-year period (i.e., three initial 2-year
survey periods, two intervening 2-year
survey periods, final 2-year survey
period), then the chemical would be
removed from the ‘Report’ and not
reinstated unless the chemical once
again met the criteria for inclusion in
the ‘Report.’ ’’
(3) The definition of
‘‘methodologically and chemically
related group.’’ Often, many similar
chemicals are measured together in the
same analytical procedure on a single
preparation of an individual specimen.
This is possible because the chemicals
share similar physical/chemical
properties and because of recent
advances in separation and detection
technologies (e.g., chromatography
followed by mass spectrometry). Such
chemicals were previously referred to as
belonging to a ‘‘methodologically and
chemically related group.’’ Because of
issues in the following discussion, the
terminology and definition have been
changed to the following: A ‘‘methodrelated group’’ is defined as a group of
chemicals that are (1) measured together
using a single analytical method; (2)
structurally similar; (3) typically
generated together from exposure
sources (e.g., dioxin congeners, furan
congeners, polyaromatic hydrocarbons);
and (4) typically assessed for health risk
together as a group.
Commenters asked whether a
chemical satisfying this criterion should
be measured in subsequent reports (as
CDC intends) only because other
chemicals in the ‘‘methodologically and
chemically related group’’ were being
reported. CDC seeks to balance both the
scientific importance and cost of
measuring specific chemicals. In regard
to scientific importance, scientists who
consider the aggregate effect of certain
chemical groups (e.g., molar sums or
toxic equivalents [TEQs]) may need to
know whether a component chemical of
a group was not detected and
noncontributory as opposed to not
measured. CDC would continue to
measure a chemical in a method-related
group that met this criterion for removal
where it would be helpful for risk
assessment of the entire group of
chemicals (e.g., dioxins).
(4) The application of the criterion to
the entire group versus individual
chemicals in the group to achieve cost
savings.
Commenters asked whether there
would not be some cost savings by not
E:\FR\FM\28MRN1.SGM
28MRN1
sroberts on PROD1PC70 with NOTICES
Federal Register / Vol. 73, No. 61 / Friday, March 28, 2008 / Notices
measuring a chemical that met a
criterion for removal among the
multiple chemicals measured in such an
assay. Removing one of a group of
related chemicals (e.g., PCBs) from the
‘‘Report’’ although it alone meets a
criterion, would generate little
additional savings. The relative cost
savings are in direct proportion to the
number of chemicals in a multichemical
analysis. Removing 1 of 26 chemicals
(e.g., PCB congeners) would save only
about 4% of the post-instrumental
analysis labor and cost of standards but
would result in little or no savings in all
other costs such as labor, supplies,
sample preparation, and instrument
analysis. Thus, if cost impact were
minimal, CDC would continue to
measure a chemical in a method-related
group that met this removal criterion.
A commenter requested the addition
of ‘‘mode of action’’ to the definition of
a chemically and methodologically
related group. Because ‘‘mode of action’’
may involve chemicals of different
structural classes and different
analytical methods, CDC chose not to
add this descriptor to the current
definition of a method-related group.
Revised draft Criterion 2: If, after three
survey periods (a period of not less than
6 years), detection rates for all
chemicals within a method-related
group are less than 5 percent for all
population subgroups (e.g., two sexes,
three race/ethnicity groups, and the age
groups used in the ‘‘Report’’).
Specific comments related to Criterion
3: If, after three survey periods ( or not
less than 6 years), levels of chemicals
within a methodologically and
chemically related group are unchanged
or declining in all the specific subgroups
as documented in the ‘‘Report.’’
Comments addressed the following:
(1) No change or declining levels over
three survey periods is not synonymous
with lessened health concerns, (2) the
criterion does not address unforeseen
increases in chemicals after their
removal from the ‘‘Report,’’ (3) whether
new demographic groups might be
added in the future and whether
criterion 3 would also apply to these
new demographic groups (e.g., people
aged 60 years and older), and (4) further
definition of unchanged or declining
levels is required.
CDC Responses related to Criterion 3:
(1) No change or declining levels over
three survey periods is not synonymous
with lessened health concerns. CDC
agrees that the phrase ‘‘no change over
a 6-year period’’ is not synonymous
with a lessened concern for certain
chemicals with possible heath risks. If,
however, there is public health concern
about a particular chemical, exception
VerDate Aug<31>2005
17:57 Mar 27, 2008
Jkt 214001
‘‘a’’ would apply. If 6 years or three
survey periods is not long enough to
evaluate a persistent chemical,
exception ‘‘b’’ would apply. In addition,
a chemical previously removed from the
‘‘Report’’ could reappear in the
‘‘Report’’ if that chemical again met the
inclusion criteria for selecting chemicals
for the ‘‘Report.’’ (see Federal Register,
Vol. 71, No. 94, May 16, 2006, pages
28346–7).
(2) The criterion does not address
unforeseen increases in levels of
chemicals after their removal from the
‘‘Report.’’ CDC agrees that criterion 3
would not address situations involving
an unforeseen rise in the level of a
chemical after its removal from future
monitoring by the ‘‘Report.’’ As it did
for criterion 2 (stated above), CDC will
include the following language: ‘‘For a
chemical that meets criterion 2 or 3, the
chemical would be removed from the
‘Report’ for two future survey periods (4
years) and then measured again in the
following survey period (2 years). If
either criterion 2 or 3 is still satisfied for
this 12-year period (i.e., three initial 2year survey periods, two intervening 2year survey periods, final 2-year survey
period), then the chemical would be
removed from the ‘Report’ and not
reinstated unless the chemical once
again met the criteria for inclusion in
the ‘Report.’’’
(3) Whether new demographic groups
might be added in the future and
whether criterion 3 would also apply to
these new demographic groups (e.g.,
people aged 60 years and older). As is
also stated above for Criterion 2,
Criterion 3 would apply to all
subgroups—listed age groups, both
sexes, and three race/ethnicities-for
which statistically sufficient data are
reported. In other words, if all but one
subgroup satisfied the criterion, it
would be important to continue
measuring the chemical. In answer to
the possibility of additional subgroups
in a future ‘‘Report,’’ CDC does intend
to divide the 20 and older age group
into two groups: 20–59 years and 60
years and older. If past and additional
(new) demographic groups all satisfy the
criterion, the chemical could be
removed. Other than this older age
group, NHANES sampling design and
statistical considerations make it
unlikely that demographic groups will
be added.
(4) Further definition of unchanged or
declining levels is required. CDC agrees
that the phrase ‘‘unchanged or
declining’’ needs further definition.
CDC has revised the wording of this
criterion by adding the following:
‘‘Evidence that chemical levels are
unchanged or declining would be the
PO 00000
Frm 00067
Fmt 4703
Sfmt 4703
16687
absence of a statistically significant
(p < 0.05) positive slope of mean (or
geometric mean) levels of the chemical
over the time period.’’
Revised draft Criterion 3: If after three
survey periods (a period of not less than
6 years), levels of chemicals within a
method-related group are unchanged or
declining in all the demographic
subgroups documented in the ‘‘Report.’’
Evidence that chemical levels are
unchanged or declining would be the
absence of a statistically significant
(p < 0.05) positive slope of mean (or
geometric mean) levels of the chemical
over the time period.
Specific comments related to
Exceptions ‘‘a’’ and ‘‘b’’: (a) It is a
chemical for which there is an
established biomonitoring health
threshold (e.g., CDC’s level of concern
for blood lead levels in children) or any
chemical for which there is widespread
public health concern (e.g., mercury), or
(b) three survey periods (or not less than
6 years) have passed, which constitute
the minimum time before a chemical
could be removed; a longer period may
be necessary to account for the half-life
of a particular chemical or to account
for a recent change (e.g., the removal of
a chemical from commerce) that would
necessitate monitoring of the
population.
Comments addressed the following:
(1) the meaning of the phrase
‘‘widespread public health concern’’ in
exception ‘‘a,’’ and (2) the rationale for
exception ‘‘b.’’
CDC Responses related to Exceptions
‘‘a’’ and ‘‘b’’:
(1) The meaning of the phrase
‘‘widespread public health concern’’: A
commenter stated that ‘‘widespread
health concern’’ was broad and vague
and wished to know what constituted
‘‘widespread concern’’ as well as the
process used to determine ‘‘widespread
concern.’’ CDC will change the sentence
in exception ‘‘a’’ that contains the
phrase ‘‘widespread public health
concern’’ to ‘‘The chemical has an
established federal biomonitoring health
threshold (e.g., CDC’s level of concern
for blood lead levels in children) or after
consultation with relevant federal
agencies, CDC learns that a federal
agency considers the chemical of
sufficient priority to warrant continued
monitoring.’’
(2) The rationale for exception ‘‘b.’’ A
commenter stated that ‘‘* * * this
exception appears to provide the CDC
with a sensible amount of flexibility; the
commenter urges CDC to provide the
rationale for applying this exception.’’
To better explain exception ‘‘b,’’ CDC
will use the following wording: ‘‘The
chemical has a long half-life (e.g., DDE),
E:\FR\FM\28MRN1.SGM
28MRN1
16688
Federal Register / Vol. 73, No. 61 / Friday, March 28, 2008 / Notices
sroberts on PROD1PC70 with NOTICES
which would require additional time to
track changes reliably in population
levels, or recent changes in exposure
sources indicate that future levels are
likely to increase.’’ Chemicals with long
half-lives in the body or persistence in
the environment may not decline
appreciably within shorter time frames
such as 6 years, and longer periods of
monitoring may be necessary to assess
whether exposure levels are changing.
Revised draft exceptions: (a) The
chemical has an established federal
biomonitoring health threshold (e.g.,
CDC’s level of concern for blood lead
levels in children) or after consultation
with relevant federal agencies, CDC
learns that a federal agency considers
the chemical of sufficient priority to
warrant continued monitoring; or (b) the
chemical has a long half-life (e.g., DDE),
which would require additional time to
track changes reliably in population
levels, or recent changes in exposure
sources indicate that future levels are
likely to increase.
Summary of Revised Draft Criteria
As stated, CDC now publicly
announces the final criteria for
removing chemicals from future releases
of the ‘‘Report.’’ These criteria will
become part of a combined process for
nominating candidate chemicals for
inclusion in or removal from the
‘‘Report.’’ The process will include (a)
nominations from the public of
candidate chemicals to include in or
remove from the ‘‘Report,’’ (b) an
external scoring of nominations in
accordance with the published
nomination and removal criteria, and (c)
assistance from the Board of Scientific
Counselors of CDC’s National Center for
Environmental Health/Agency for Toxic
Substances and Disease Registry in
reviewing plans for including or
removing chemicals and identifying
alternatives for monitoring specific atrisk population subgroups. This
combined process will occur
periodically (e.g., every 6 years). Note
that the criteria for selecting and
removing chemicals apply only to
chemicals published in the ‘‘Report’’—
not to those merely nominated.
The final removal criteria are as
follows: A chemical will be removed
from the ‘‘Report’’ if it meets any one of
the following three criteria and does not
meet either of the exceptions to those
criteria. Accordingly, a chemical will be
removed if (1) a new replacement
chemical (i.e., a metabolite or other
chemical) is more representative of
exposure than the chemical currently
measured; or (2) if after three survey
periods (a period of not less than 6
years), detection rates for all chemicals
VerDate Aug<31>2005
17:57 Mar 27, 2008
Jkt 214001
within a method-related group are less
than 5 percent for all population
subgroups (i.e., two sexes, three race/
ethnicity groups, and the age groups
used in the ‘‘Report’’) or; (3) if after
three survey periods (a period of not
less than 6 years), levels of chemicals
within a method-related group are
unchanged or declining in all the
demographic subgroups documented in
the ‘‘Report.’’ Evidence that chemical
levels are unchanged or declining
would be the absence of a statistically
significant (p < 0.05) positive slope of
mean (or geometric mean) levels of the
chemical over the time period.
For a chemical that meets criterion 1,
the chemical would be removed from
future reports and would be replaced
with the new chemical that better
reflects exposure.
For a chemical that meets criterion 2
or 3, the chemical would be removed
from the ‘‘Report’’ for two future survey
periods (4 years) then measured again in
the following survey period (2 years). If
either criterion 2 or 3 is still satisfied for
this 12-year period (three initial 2-year
survey periods, two intervening 2-year
survey periods, final 2-year survey
period), then the chemical would be
removed from the ‘‘Report’’ and not
reinstated unless the chemical once
again met the criteria for inclusion in
the ‘‘Report.’’
A chemical would continue to be
measured and not be removed from the
‘‘Report’’ if it met either of two
exceptions to the above-cited revised
draft criteria: (a) The chemical has an
established federal biomonitoring health
threshold (e.g., CDC’s level of concern
for blood lead levels in children) or after
consultation with relevant federal
agencies CDC learns that a federal
agency considers the chemical of
sufficient priority to warrant continued
monitoring; or (b) the chemical has a
long half-life (e.g., DDE), which would
require additional time to track changes
reliably in population levels, or recent
changes in exposure sources indicate
that future levels are likely to increase.
FOR FURTHER INFORMATION CONTACT:
Dorothy Sussman, Telephone 770–488–
7950.
SUPPLEMENTARY INFORMATION: CDC
publishes the ‘‘Report’’ under
authorities 42 U.S.C. 241 and 42 U.S.C.
242k. The ‘‘Report’’ provides ongoing
assessment using biomonitoring of the
exposure of the noninstitutionalized,
civilian population to environmental
chemicals. Biomonitoring assesses
human exposure to chemicals by
measuring the chemicals or their
metabolites in human specimens such
as blood or urine. For the ‘‘Report,’’ the
PO 00000
Frm 00068
Fmt 4703
Sfmt 4703
term environmental chemical means a
chemical compound or chemical
element present in air, water, soil, dust,
food, or other environmental medium.
The ‘‘Report’’ provides exposure
information about participants in an
ongoing national survey known as the
National Health and Nutrition
Examination Survey (NHANES). This
survey is conducted by CDC’s National
Center for Health Statistics;
measurements are conducted by CDC’s
National Center for Environmental
Health. The first ‘‘Report,’’ published in
March 2001, gave information about
levels of 27 chemicals found in the U.S.
population; the second ‘‘Report’’ was
published in January 2003, and it
contained exposure information on 116
chemicals, including the 27 chemicals
in the first ‘‘Report.’’ The third ‘‘Report’’
was published in July 2005, and it
contained exposure information on 148
chemicals, including data on the
chemicals published in the second
‘‘Report.’’ Copies of the third ‘‘Report’’
can be obtained in the following ways:
Access https://www.cdc.gov/
exposurereport, send an e-mail to
cdcinfo@cdc.gov, or telephone 1–800–
CDC–INFO.
Dated: March 25, 2008.
Kenneth Rose,
Director, Office of Policy, Planning, and
Evaluation, National Center for
Environmental Health/Agency for Toxic
Substances and Disease Registry.
[FR Doc. E8–6350 Filed 3–27–08; 8:45 am]
BILLING CODE 4163–18–P
DEPARTMENT OF HEALTH AND
HUMAN SERVICES
Centers for Medicare & Medicaid
Services
[CMS–2276–FN]
Medicare and Medicaid Programs;
Approval of the Community Health
Accreditation Program for Continued
Deeming Authority for Home Health
Agencies
Centers for Medicare &
Medicaid Services (CMS), HHS.
ACTION: Final Notice.
AGENCY:
SUMMARY: This final notice announces
our decision to approve the Community
Health Accreditation Program (CHAP)
for recognition as a national
accreditation program for home health
agencies (HHAs) seeking to participate
in the Medicare or Medicaid programs.
DATES: Effective Date: This final notice
is effective March 31, 2008 through
March 31, 2012.
FOR FURTHER INFORMATION CONTACT:
E:\FR\FM\28MRN1.SGM
28MRN1
]]>Agencies
[Federal Register Volume 73, Number 61 (Friday, March 28, 2008)]
[Notices]
[Pages 16685-16688]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-6350]
-----------------------------------------------------------------------
DEPARTMENT OF HEALTH AND HUMAN SERVICES
Centers for Disease Control and Prevention
[ATSDR-241]
Public Comments and Revised Final Criteria for Removing Chemicals
From Future Editions of CDC's National Report on Human Exposure to
Environmental Chemicals
AGENCY: Centers for Disease Control and Prevention (CDC), Department of
Health and Human Services (HHS).
SUMMARY: On Tuesday, May 16, 2006, CDC published draft criteria for
removing chemicals from future releases of CDC's National Report on
Human Exposure to Environmental Chemicals (the ``Report'') (See FR,
Vol. 71, No. 94, p. 28346-7). This and previous notices related to the
``Report'' are at https://www.cdc.gov/exposurereport/chemical_nominations.htm. The proposed criteria provided that a chemical may be
removed from the ``Report'' if (1) a new replacement chemical (i.e., a
metabolite) is more representative of exposure than is the chemical
currently measured; or (2) after three survey periods (or not less than
6 years), detection rates for all chemicals within a methodological and
chemically related group are less than 5 percent for all population
subgroups (i.e., two sexes, three race/ethnicity groups, and three age
groups); or (3) after three survey periods (or not less than 6 years),
levels of chemicals within a methodological and chemically related
group are unchanged or declining in all the specific subgroups as
documented in the ``Report.''
Using these criteria, CDC would have continued to measure the
chemical and not remove it from the ``Report'' if it met either of two
proposed exceptions to these criteria: (a) It is a chemical for which
there is an established biomonitoring threshold (e.g., CDC's level of
concern for blood lead levels in children) or any chemical for which
there is widespread public health concern (e.g., mercury) or (b) three
survey periods (or not less than 6 years) have passed, constituting the
minimum time before a chemical could be removed; a longer period may be
necessary to account for the half-life of a particular chemical or to
account for a recent change (e.g., the removal of a chemical from
commerce) that would necessitate monitoring of the population. In that
notice, CDC pointed out that the criteria for removing a chemical from
the ``Report'' are not corollaries of the criteria for adding chemicals
to the ``Report.''
Summary of Public Comments
CDC received 31 public comments on the criteria cited above and
describes below the comments received and CDC's responses to those
comments. Comments are grouped in the following categories: Removal
process, criterion 1, criterion 2, criterion 3, and exceptions ``a''
and ``b.''
General Informational Comments Related to Process and Procedure
CDC received several public comments about how the process of
removing chemicals from the ``Report'' would be implemented. These
generally pertained to (1) concurrence on the scientific basis for
exposure assessment; (2) analytical cost considerations as secondary;
(3) description of the policy basis for the process; (4) consideration
of and suggestions for alternative approaches to limited sample
volumes; and (5) affirmation of decision procedures, transparency, and
public notification.
CDC responses to general informational comments:
Understanding exposures through biomonitoring can help scientists
focus research on those chemicals found in people's bodies and target
the appropriate levels of exposure. The ``Report'' provides unique
exposure assessment information and not assessment of health risk.
However, the biomonitoring data in the ``Report'' can facilitate and
complement the risk-assessment process. For some chemicals, such as
lead and mercury, risks have become better characterized when
biomonitoring levels have become the benchmark to which the risks are
tied. CDC considers the public health utility and quality of
biomonitoring information to be the primary consideration, with cost of
analysis as an important, but secondary, consideration (See Federal
Register Vol. 67, No. 34 March 20, 2002, pages 12996-7).
The policy basis for the development of criteria for removing
chemicals from the ``Report'' was developed in consideration of sound
science and resource utilization. With guidance from a Work Group that
was convened at the direction of the Board of Scientific Counselors of
the National Center for Environmental Health and the Agency for Toxic
Substances and Disease Registry (NCEH/ATSDR), the proposed criteria
were established, and comments from the public were solicited through
the Federal Register notice published in May 2006 (Vol. 71, No. 94, p.
28346-7).
As currently described, only one of the three criteria needs to
apply to delist a chemical. That is, the three criteria apply
independently--no combinations of criteria are necessary to qualify a
chemical for removal from the ``Report.'' When chemicals published in
the ``Report'' meet a criterion for removal, they will be deleted from
future reports. The Division of Laboratory Sciences (DLS) at NCEH will
make these decisions using the finalized criteria only and will post
the names of the removed chemicals on its Web site: https://www.cdc.gov/exposurereport.
Two commenters provided helpful suggestions for maintaining
flexibility in applying the removal process and suggested alternative
plans for optimal use of samples. For those chemicals requiring large
amounts of sample volume to detect the chemicals, alternatives such as
less frequent sampling or pooled analyses are appropriate alternatives.
CDC has actively researched these alternatives and will continue to
weigh the relative cost-benefit of other approaches in addressing the
issue of limited sample volume. Such approaches could include less
frequent sampling, pooling of samples, and development of more
sensitive analytical methods. For difficult decisions, the NCEH/ATSDR
[[Page 16686]]
Board of Scientific Counselors will be consulted for advice on the use
of alternative approaches.
This process of announcing draft criteria and requesting comment on
the criteria was the first step in ensuring transparency. Commenters'
involvement in this process is evidence of CDC's efforts to involve
multiple groups with varied viewpoints. CDC will announce the process
for both nominating and removing chemicals from the ``Report'' in a
future Federal Register notice. When chemicals are removed through this
process, announcements will be made on CDC's Web site (https://www.cdc.gov/exposurereport). Descriptions of ongoing activities related
to the ``Report'' have been provided in public meetings with advisory
groups, in regional and national conferences, through publication of
introductory material in the ``Report'' itself, in previous Federal
Register announcements, and in postings of these materials on the CDC
Web site.
Specific comments related to Criterion 1: If a new replacement
chemical (i.e., a metabolite) is more representative of exposure than
the chemical currently being measured.
Two specific comments and one general comment were received.
CDC Responses related to Criterion 1:
The first comment recommends a phased overlap in the analysis of
the previously measured chemical with the replacement chemical. CDC
agrees with this recommendation, which would occur naturally in the
course of the scientific accrual of knowledge and measurements about
the new replacement chemical. Both old and replacement chemicals may
exist in the ``Report'' simultaneously until such knowledge and
experience are accrued.
The second comment requested a wording change in criterion 1 from
``(i.e., a metabolite)'' to ``(i.e., a metabolite or other chemical).''
The wording change is accepted.
A general comment was made that the meaning of the phrase ``is more
representative of exposure'' can be inferred. CDC notes that a
replacement chemical is more representative of exposure when the
measured concentration of the replacement chemical accounts for a
greater fraction of the dose or has pharmacokinetic characteristics
that decrease the variability in exposure estimation (such as longer
persistence in the body).
Revised draft Criterion 1: If a new replacement chemical (i.e., a
metabolite or other chemical) is more representative of exposure than
the chemical currently being measured.
Specific comments related to Criterion 2: If after three survey
periods (or not less than 6 years), detection rates for all chemicals
within a methodologically and chemically related group are less than 5
percent for all population subgroups (e.g., two sexes, three race/
ethnicity groups, and three age groups).
CDC received six overlapping comments from different commenters on
the description or discussion of the following: (1) The requirement of
a 5% detection rate for all population subgroups to meet the criterion;
(2) the adequate number of survey periods applicable to the criterion;
(3) the definition of ``methodological and chemically related group'';
and (4) the application of the criterion to the entire group versus
individual chemicals in the group to achieve cost savings.
CDC Responses Related to Criterion 2
(1) The requirement of a 5% detection rate. Not removing a chemical
from the ``Report'' until all reported subgroups have fallen below the
5% detection rate is a conservative approach, allowing continued
population monitoring even though some subgroups would no longer meet
that criterion. A 5% detection rate allows an estimate of the 95th
percentile for a population group. The 95th percentile is extremely
useful for characterizing levels of unusual exposure in a population.
If removal of a chemical from the ``Report'' resulted by meeting this
criterion, but there were known exposures to special groups that are of
public health interest, targeted monitoring studies could be
recommended. CDC may be able to assist some states or other agencies in
biomonitoring of special groups with unusual potential for exposure or
who potentially may be at more risk for adverse health effects.
(2) The adequate number of survey periods applicable to the
criterion. No absolute guide governs the number of survey periods
necessary for inclusion in this criterion. CDC considered three survey
periods because this number was the minimum number of survey point
estimates from which trends might be calculated. Still, environmental
conditions and releases of chemicals may change human exposures over
time, and for some persistent chemicals--that is, persistent either in
the body or in the environment--the 6-year period would be too short to
measure a meaningful change. Thus, to accommodate these situations, CDC
added exemption ``b.'' CDC has also rephrased the following statement
to address reassessment of a chemical removed from the ``Report'' under
either criterion 2 or 3: ``For a chemical that meets criterion 2 or 3,
the chemical would be removed from the `Report' for two future survey
periods (4 years) and then measured again in the following survey
period (2 years). If either criterion 2 or 3 is still satisfied for
this 12-year period (i.e., three initial 2-year survey periods, two
intervening 2-year survey periods, final 2-year survey period), then
the chemical would be removed from the `Report' and not reinstated
unless the chemical once again met the criteria for inclusion in the
`Report.' ''
(3) The definition of ``methodologically and chemically related
group.'' Often, many similar chemicals are measured together in the
same analytical procedure on a single preparation of an individual
specimen. This is possible because the chemicals share similar
physical/chemical properties and because of recent advances in
separation and detection technologies (e.g., chromatography followed by
mass spectrometry). Such chemicals were previously referred to as
belonging to a ``methodologically and chemically related group.''
Because of issues in the following discussion, the terminology and
definition have been changed to the following: A ``method-related
group'' is defined as a group of chemicals that are (1) measured
together using a single analytical method; (2) structurally similar;
(3) typically generated together from exposure sources (e.g., dioxin
congeners, furan congeners, polyaromatic hydrocarbons); and (4)
typically assessed for health risk together as a group.
Commenters asked whether a chemical satisfying this criterion
should be measured in subsequent reports (as CDC intends) only because
other chemicals in the ``methodologically and chemically related
group'' were being reported. CDC seeks to balance both the scientific
importance and cost of measuring specific chemicals. In regard to
scientific importance, scientists who consider the aggregate effect of
certain chemical groups (e.g., molar sums or toxic equivalents [TEQs])
may need to know whether a component chemical of a group was not
detected and noncontributory as opposed to not measured. CDC would
continue to measure a chemical in a method-related group that met this
criterion for removal where it would be helpful for risk assessment of
the entire group of chemicals (e.g., dioxins).
(4) The application of the criterion to the entire group versus
individual chemicals in the group to achieve cost savings.
Commenters asked whether there would not be some cost savings by
not
[[Page 16687]]
measuring a chemical that met a criterion for removal among the
multiple chemicals measured in such an assay. Removing one of a group
of related chemicals (e.g., PCBs) from the ``Report'' although it alone
meets a criterion, would generate little additional savings. The
relative cost savings are in direct proportion to the number of
chemicals in a multichemical analysis. Removing 1 of 26 chemicals
(e.g., PCB congeners) would save only about 4% of the post-instrumental
analysis labor and cost of standards but would result in little or no
savings in all other costs such as labor, supplies, sample preparation,
and instrument analysis. Thus, if cost impact were minimal, CDC would
continue to measure a chemical in a method-related group that met this
removal criterion.
A commenter requested the addition of ``mode of action'' to the
definition of a chemically and methodologically related group. Because
``mode of action'' may involve chemicals of different structural
classes and different analytical methods, CDC chose not to add this
descriptor to the current definition of a method-related group.
Revised draft Criterion 2: If, after three survey periods (a period
of not less than 6 years), detection rates for all chemicals within a
method-related group are less than 5 percent for all population
subgroups (e.g., two sexes, three race/ethnicity groups, and the age
groups used in the ``Report'').
Specific comments related to Criterion 3: If, after three survey
periods ( or not less than 6 years), levels of chemicals within a
methodologically and chemically related group are unchanged or
declining in all the specific subgroups as documented in the
``Report.''
Comments addressed the following: (1) No change or declining levels
over three survey periods is not synonymous with lessened health
concerns, (2) the criterion does not address unforeseen increases in
chemicals after their removal from the ``Report,'' (3) whether new
demographic groups might be added in the future and whether criterion 3
would also apply to these new demographic groups (e.g., people aged 60
years and older), and (4) further definition of unchanged or declining
levels is required.
CDC Responses related to Criterion 3:
(1) No change or declining levels over three survey periods is not
synonymous with lessened health concerns. CDC agrees that the phrase
``no change over a 6-year period'' is not synonymous with a lessened
concern for certain chemicals with possible heath risks. If, however,
there is public health concern about a particular chemical, exception
``a'' would apply. If 6 years or three survey periods is not long
enough to evaluate a persistent chemical, exception ``b'' would apply.
In addition, a chemical previously removed from the ``Report'' could
reappear in the ``Report'' if that chemical again met the inclusion
criteria for selecting chemicals for the ``Report.'' (see Federal
Register, Vol. 71, No. 94, May 16, 2006, pages 28346-7).
(2) The criterion does not address unforeseen increases in levels
of chemicals after their removal from the ``Report.'' CDC agrees that
criterion 3 would not address situations involving an unforeseen rise
in the level of a chemical after its removal from future monitoring by
the ``Report.'' As it did for criterion 2 (stated above), CDC will
include the following language: ``For a chemical that meets criterion 2
or 3, the chemical would be removed from the `Report' for two future
survey periods (4 years) and then measured again in the following
survey period (2 years). If either criterion 2 or 3 is still satisfied
for this 12-year period (i.e., three initial 2-year survey periods, two
intervening 2-year survey periods, final 2-year survey period), then
the chemical would be removed from the `Report' and not reinstated
unless the chemical once again met the criteria for inclusion in the
`Report.'''
(3) Whether new demographic groups might be added in the future and
whether criterion 3 would also apply to these new demographic groups
(e.g., people aged 60 years and older). As is also stated above for
Criterion 2, Criterion 3 would apply to all subgroups--listed age
groups, both sexes, and three race/ethnicities-for which statistically
sufficient data are reported. In other words, if all but one subgroup
satisfied the criterion, it would be important to continue measuring
the chemical. In answer to the possibility of additional subgroups in a
future ``Report,'' CDC does intend to divide the 20 and older age group
into two groups: 20-59 years and 60 years and older. If past and
additional (new) demographic groups all satisfy the criterion, the
chemical could be removed. Other than this older age group, NHANES
sampling design and statistical considerations make it unlikely that
demographic groups will be added.
(4) Further definition of unchanged or declining levels is
required. CDC agrees that the phrase ``unchanged or declining'' needs
further definition. CDC has revised the wording of this criterion by
adding the following: ``Evidence that chemical levels are unchanged or
declining would be the absence of a statistically significant (p <
0.05) positive slope of mean (or geometric mean) levels of the chemical
over the time period.''
Revised draft Criterion 3: If after three survey periods (a period
of not less than 6 years), levels of chemicals within a method-related
group are unchanged or declining in all the demographic subgroups
documented in the ``Report.'' Evidence that chemical levels are
unchanged or declining would be the absence of a statistically
significant (p < 0.05) positive slope of mean (or geometric mean)
levels of the chemical over the time period.
Specific comments related to Exceptions ``a'' and ``b'': (a) It is
a chemical for which there is an established biomonitoring health
threshold (e.g., CDC's level of concern for blood lead levels in
children) or any chemical for which there is widespread public health
concern (e.g., mercury), or (b) three survey periods (or not less than
6 years) have passed, which constitute the minimum time before a
chemical could be removed; a longer period may be necessary to account
for the half-life of a particular chemical or to account for a recent
change (e.g., the removal of a chemical from commerce) that would
necessitate monitoring of the population.
Comments addressed the following: (1) the meaning of the phrase
``widespread public health concern'' in exception ``a,'' and (2) the
rationale for exception ``b.''
CDC Responses related to Exceptions ``a'' and ``b'':
(1) The meaning of the phrase ``widespread public health concern'':
A commenter stated that ``widespread health concern'' was broad and
vague and wished to know what constituted ``widespread concern'' as
well as the process used to determine ``widespread concern.'' CDC will
change the sentence in exception ``a'' that contains the phrase
``widespread public health concern'' to ``The chemical has an
established federal biomonitoring health threshold (e.g., CDC's level
of concern for blood lead levels in children) or after consultation
with relevant federal agencies, CDC learns that a federal agency
considers the chemical of sufficient priority to warrant continued
monitoring.''
(2) The rationale for exception ``b.'' A commenter stated that ``*
* * this exception appears to provide the CDC with a sensible amount of
flexibility; the commenter urges CDC to provide the rationale for
applying this exception.'' To better explain exception ``b,'' CDC will
use the following wording: ``The chemical has a long half-life (e.g.,
DDE),
[[Page 16688]]
which would require additional time to track changes reliably in
population levels, or recent changes in exposure sources indicate that
future levels are likely to increase.'' Chemicals with long half-lives
in the body or persistence in the environment may not decline
appreciably within shorter time frames such as 6 years, and longer
periods of monitoring may be necessary to assess whether exposure
levels are changing.
Revised draft exceptions: (a) The chemical has an established
federal biomonitoring health threshold (e.g., CDC's level of concern
for blood lead levels in children) or after consultation with relevant
federal agencies, CDC learns that a federal agency considers the
chemical of sufficient priority to warrant continued monitoring; or (b)
the chemical has a long half-life (e.g., DDE), which would require
additional time to track changes reliably in population levels, or
recent changes in exposure sources indicate that future levels are
likely to increase.
Summary of Revised Draft Criteria
As stated, CDC now publicly announces the final criteria for
removing chemicals from future releases of the ``Report.'' These
criteria will become part of a combined process for nominating
candidate chemicals for inclusion in or removal from the ``Report.''
The process will include (a) nominations from the public of candidate
chemicals to include in or remove from the ``Report,'' (b) an external
scoring of nominations in accordance with the published nomination and
removal criteria, and (c) assistance from the Board of Scientific
Counselors of CDC's National Center for Environmental Health/Agency for
Toxic Substances and Disease Registry in reviewing plans for including
or removing chemicals and identifying alternatives for monitoring
specific at-risk population subgroups. This combined process will occur
periodically (e.g., every 6 years). Note that the criteria for
selecting and removing chemicals apply only to chemicals published in
the ``Report''--not to those merely nominated.
The final removal criteria are as follows: A chemical will be
removed from the ``Report'' if it meets any one of the following three
criteria and does not meet either of the exceptions to those criteria.
Accordingly, a chemical will be removed if (1) a new replacement
chemical (i.e., a metabolite or other chemical) is more representative
of exposure than the chemical currently measured; or (2) if after three
survey periods (a period of not less than 6 years), detection rates for
all chemicals within a method-related group are less than 5 percent for
all population subgroups (i.e., two sexes, three race/ethnicity groups,
and the age groups used in the ``Report'') or; (3) if after three
survey periods (a period of not less than 6 years), levels of chemicals
within a method-related group are unchanged or declining in all the
demographic subgroups documented in the ``Report.'' Evidence that
chemical levels are unchanged or declining would be the absence of a
statistically significant (p < 0.05) positive slope of mean (or
geometric mean) levels of the chemical over the time period.
For a chemical that meets criterion 1, the chemical would be
removed from future reports and would be replaced with the new chemical
that better reflects exposure.
For a chemical that meets criterion 2 or 3, the chemical would be
removed from the ``Report'' for two future survey periods (4 years)
then measured again in the following survey period (2 years). If either
criterion 2 or 3 is still satisfied for this 12-year period (three
initial 2-year survey periods, two intervening 2-year survey periods,
final 2-year survey period), then the chemical would be removed from
the ``Report'' and not reinstated unless the chemical once again met
the criteria for inclusion in the ``Report.''
A chemical would continue to be measured and not be removed from
the ``Report'' if it met either of two exceptions to the above-cited
revised draft criteria: (a) The chemical has an established federal
biomonitoring health threshold (e.g., CDC's level of concern for blood
lead levels in children) or after consultation with relevant federal
agencies CDC learns that a federal agency considers the chemical of
sufficient priority to warrant continued monitoring; or (b) the
chemical has a long half-life (e.g., DDE), which would require
additional time to track changes reliably in population levels, or
recent changes in exposure sources indicate that future levels are
likely to increase.
FOR FURTHER INFORMATION CONTACT: Dorothy Sussman, Telephone 770-488-
7950.
SUPPLEMENTARY INFORMATION: CDC publishes the ``Report'' under
authorities 42 U.S.C. 241 and 42 U.S.C. 242k. The ``Report'' provides
ongoing assessment using biomonitoring of the exposure of the
noninstitutionalized, civilian population to environmental chemicals.
Biomonitoring assesses human exposure to chemicals by measuring the
chemicals or their metabolites in human specimens such as blood or
urine. For the ``Report,'' the term environmental chemical means a
chemical compound or chemical element present in air, water, soil,
dust, food, or other environmental medium. The ``Report'' provides
exposure information about participants in an ongoing national survey
known as the National Health and Nutrition Examination Survey (NHANES).
This survey is conducted by CDC's National Center for Health
Statistics; measurements are conducted by CDC's National Center for
Environmental Health. The first ``Report,'' published in March 2001,
gave information about levels of 27 chemicals found in the U.S.
population; the second ``Report'' was published in January 2003, and it
contained exposure information on 116 chemicals, including the 27
chemicals in the first ``Report.'' The third ``Report'' was published
in July 2005, and it contained exposure information on 148 chemicals,
including data on the chemicals published in the second ``Report.''
Copies of the third ``Report'' can be obtained in the following ways:
Access https://www.cdc.gov/exposurereport, send an e-mail to
cdcinfo@cdc.gov, or telephone 1-800-CDC-INFO.
Dated: March 25, 2008.
Kenneth Rose,
Director, Office of Policy, Planning, and Evaluation, National Center
for Environmental Health/Agency for Toxic Substances and Disease
Registry.
[FR Doc. E8-6350 Filed 3-27-08; 8:45 am]
BILLING CODE 4163-18-P
