Propazine; Notice of Filing a Pesticide Petition to Establish a Tolerance for a Certain Pesticide Chemical in or on Food, 36159-36164 [05-12015]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 70, Number 119 (Wednesday, June 22, 2005)]
[Notices]
[Pages 36159-36164]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-12015]


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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2005-0032; FRL-7718-7]


Propazine; Notice of Filing a Pesticide Petition to Establish a 
Tolerance for a Certain Pesticide Chemical in or on Food

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: This notice announces the initial filing of a pesticide 
petition proposing the establishment of regulations for residues of a 
certain pesticide chemical in or on various food commodities.

DATES: Comments, identified by docket identification (ID) number OPP-
2005-0032, must be received on or before July 22, 2005.

ADDRESSES: Comments may be submitted electronically, by mail, or 
through hand delivery/courier. Follow the detailed instructions as 
provided in Unit I. of the SUPPLEMENTARY INFORMATION.

FOR FURTHER INFORMATION CONTACT: Jim Tompkins, Registration Division 
(7505C), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 305-5697; e-mail address: tompkins.jim@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you an 
agricultural producer, food manufacturer, or

[[Page 36160]]

pesticide manufacturer. Potentially affected entities may include, but 
are not limited to:
     Crop production (NAICS 111)
     Animal production (NAICS 112)
     Food manufacturing (NAICS 311)
     Pesticide manufacturing (NAICS 32532)
     This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in this unit could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether this action might apply to certain entities. If you have any 
questions regarding the applicability of this action to a particular 
entity, consult the person listed under FOR FURTHER INFORMATION 
CONTACT.

B. How Can I Get Copies of this Document and Other Related Information?

    1. Docket. EPA has established an official public docket for this 
action under docket ID number OPP-2005-0032. The official public docket 
consists of the documents specifically referenced in this action, any 
public comments received, and other information related to this action. 
Although, a part of the official docket, the public docket does not 
include Confidential Business Information (CBI) or other information 
whose disclosure is restricted by statute. The official public docket 
is the collection of materials that is available for public viewing at 
the Public Information and Records Integrity Branch (PIRIB), Rm. 119, 
Crystal Mall 2, 1801 S. Bell St., Arlington, VA. This docket 
facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. The docket telephone number is (703) 305-
5805.
    2. Electronic access. You may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at https://www.epa.gov/fedrgstr/.
    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at https://www.epa.gov/edocket/ to submit or view public 
comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Although, not all docket materials may be 
available electronically, you may still access any of the publicly 
available docket materials through the docket facility identified in 
Unit I.B.1. Once in the system, select ``search,'' then key in the 
appropriate docket ID number.
    Certain types of information will not be placed in the EPA Dockets. 
Information claimed as CBI and other information whose disclosure is 
restricted by statute, which is not included in the official public 
docket, will not be available for public viewing in EPA's electronic 
public docket. EPA's policy is that copyrighted material will not be 
placed in EPA's electronic public docket but will be available only in 
printed, paper form in the official public docket. To the extent 
feasible, publicly available docket materials will be made available in 
EPA's electronic public docket. When a document is selected from the 
index list in EPA Dockets, the system will identify whether the 
document is available for viewing in EPA's electronic public docket. 
Although, not all docket materials may be available electronically, you 
may still access any of the publicly available docket materials through 
the docket facility identified in Unit I.B. EPA intends to work towards 
providing electronic access to all of the publicly available docket 
materials through EPA's electronic public docket.
    For public commenters, it is important to note that EPA's policy is 
that public comments, whether submitted electronically or on paper, 
will be made available for public viewing in EPA's electronic public 
docket as EPA receives them and without change, unless the comment 
contains copyrighted material, CBI, or other information whose 
disclosure is restricted by statute. When EPA identifies a comment 
containing copyrighted material, EPA will provide a reference to that 
material in the version of the comment that is placed in EPA's 
electronic public docket. The entire printed comment, including the 
copyrighted material, will be available in the public docket.
    Public comments submitted on computer disks that are mailed or 
delivered to the docket will be transferred to EPA's electronic public 
docket. Public comments that are mailed or delivered to the docket will 
be scanned and placed in EPA's electronic public docket. Where 
practical, physical objects will be photographed, and the photograph 
will be placed in EPA's electronic public docket along with a brief 
description written by the docket staff.

C. How and to Whom Do I Submit Comments?

    You may submit comments electronically, by mail, or through hand 
delivery/courier. To ensure proper receipt by EPA, identify the 
appropriate docket ID number in the subject line on the first page of 
your comment. Please ensure that your comments are submitted within the 
specified comment period. Comments received after the close of the 
comment period will be marked ``late.'' EPA is not required to consider 
these late comments. If you wish to submit CBI or information that is 
otherwise protected by statute, please follow the instructions in Unit 
I.D. Do not use EPA Dockets or e-mail to submit CBI or information 
protected by statute.
    1. Electronically. If you submit an electronic comment as 
prescribed in this unit, EPA recommends that you include your name, 
mailing address, and an e-mail address or other contact information in 
the body of your comment. Also, include this contact information on the 
outside of any disk or CD ROM you submit, and in any cover letter 
accompanying the disk or CD ROM. This ensures that you can be 
identified as the submitter of the comment and allows EPA to contact 
you in case EPA cannot read your comment due to technical difficulties 
or needs further information on the substance of your comment. EPA's 
policy is that EPA will not edit your comment, and any identifying or 
contact information provided in the body of a comment will be included 
as part of the comment that is placed in the official public docket, 
and made available in EPA's electronic public docket. If EPA cannot 
read your comment due to technical difficulties and cannot contact you 
for clarification, EPA may not be able to consider your comment.
    i. EPA Dockets. Your use of EPA's electronic public docket to 
submit comments to EPA electronically is EPA's preferred method for 
receiving comments. Go directly to EPA Dockets at https://www.epa.gov/
edocket/, and follow the online instructions for submitting comments. 
Once in the system, select ``search,'' and then key in docket ID number 
OPP-2005-0032. The system is an ``anonymous access'' system, which 
means EPA will not know your identity, e-mail address, or other contact 
information unless you provide it in the body of your comment.
    ii. E-mail. Comments may be sent by e-mail to opp-docket@epa.gov, 
Attention: Docket ID number OPP-2005-0032. In contrast to EPA's 
electronic public docket, EPA's e-mail system is not an ``anonymous 
access'' system. If you send an e-mail comment directly to the docket 
without going through EPA's electronic public docket, EPA's e-mail 
system automatically captures your e-mail address. E-mail addresses 
that are automatically

[[Page 36161]]

captured by EPA's e-mail system are included as part of the comment 
that is placed in the official public docket, and made available in 
EPA's electronic public docket.
    iii. Disk or CD ROM. You may submit comments on a disk or CD ROM 
that you mail to the mailing address identified in Unit I.C.2. These 
electronic submissions will be accepted in WordPerfect or ASCII file 
format. Avoid the use of special characters and any form of encryption.
    2. By mail. Send your comments to: Public Information and Records 
Integrity Branch (PIRIB) (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001, Attention: Docket ID number OPP-2005-0032.
    3. By hand delivery or courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Office of Pesticide 
Programs (OPP), Environmental Protection Agency, Rm. 119, Crystal Mall 
2, 1801 S. Bell St., Arlington, VA, Attention: Docket ID 
number OPP-2005-0032. Such deliveries are only accepted during the 
docket's normal hours of operation as identified in Unit I.B.1.

D. How Should I Submit CBI to the Agency?

     Do not submit information that you consider to be CBI 
electronically through EPA's electronic public docket or by e-mail. You 
may claim information that you submit to EPA as CBI by marking any part 
or all of that information as CBI (if you submit CBI on disk or CD ROM, 
mark the outside of the disk or CD ROM as CBI and then identify 
electronically within the disk or CD ROM the specific information that 
is CBI). Information so marked will not be disclosed except in 
accordance with procedures set forth in 40 CFR part 2.
     In addition to one complete version of the comment that includes 
any information claimed as CBI, a copy of the comment that does not 
contain the information claimed as CBI must be submitted for inclusion 
in the public docket and EPA's electronic public docket. If you submit 
the copy that does not contain CBI on disk or CD ROM, mark the outside 
of the disk or CD ROM clearly that it does not contain CBI. Information 
not marked as CBI will be included in the public docket and EPA's 
electronic public docket without prior notice. If you have any 
questions about CBI or the procedures for claiming CBI, please consult 
the person listed under FOR FURTHER INFORMATION CONTACT.

E. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide copies of any technical information and/or data you used 
that support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at the estimate that you provide.
    5. Provide specific examples to illustrate your concerns.
    6. Make sure to submit your comments by the deadline in this 
notice.
    7. To ensure proper receipt by EPA, be sure to identify the docket 
ID number assigned to this action in the subject line on the first page 
of your response. You may also provide the name, date, and Federal 
Register citation.

II. What Action is the Agency Taking?

    EPA has received a pesticide petition as follows proposing the 
establishment and/or amendment of regulations for residues of a certain 
pesticide chemical in or on various food commodities under section 408 
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a. 
EPA has determined that this petition contains data or information 
regarding the elements set forth in FFDCA section 408(d)(2); however, 
EPA has not fully evaluated the sufficiency of the submitted data at 
this time or whether the data support granting of the petition. 
Additional data may be needed before EPA rules on the petition.

List of Subjects

     Environmental protection, Agricultural commodities, Feed 
additives, Food additives, Pesticides and pests, Reporting and 
recordkeeping requirements.

    Dated: June 3, 2005.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

Summary of Petition

    The petitioner's summary of the pesticide petition is printed below 
as required by FFDCA section 408(d)(3). The summary of the petition was 
prepared by Griffin Corporation, and represents the view of the 
petitioner. The petition summary announces the availability of a 
description of the analytical methods available to EPA for the 
detection and measurement of the pesticide chemical residues or an 
explanation of why no such method is needed.

 Griffin Corporation

 PP 7F4837

     EPA has received a pesticide petition (PP 7F4837) from Griffin 
Corporation, P.O. Box 1847, Valdosta, GA 31603-1847 proposing, pursuant 
to section 408(d) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 
21 U.S.C. 346a(d), to amend 40 CFR part 180, by establishing a 
tolerance for residues of propazine 2-chloro-4,6- bis(isopropyamine)-s-
triazine and its 2 chloro metabolites, 2-amino-4-chloro, 6-
isopropylamino-s-triazine (G-30033) and 2,4-diamino-6-chloro-striazine 
(G-28273) in or on the raw agricultural commodity sorghum, stover, 
forage, and grain at 0.25 parts per million (ppm). EPA has determined 
that the petition contains data or information regarding the elements 
set forth in section 408(d)(2) of the FFDCA; however, EPA has not fully 
evaluated the sufficiency of the submitted data at this time or whether 
the data support granting of the petition. Additional data may be 
needed before EPA rules on the petition.

A. Residue Chemistry

    1. Plant metabolism. In sorghum, metabolism occurs by the three 
following reactions: N-dealkylation of the side-chains, hydrolytic 
dehalogenation or nucleophilic displacement of the 2-chloro group with 
glutathione (GSH). The dehalogenation and formation of GSH conjugates 
are the two predominant pathways and only small amounts of the chloro 
residues were found in forage and stover. No chloro residues were 
detected in sorghum grain in two propazine metabolism studies that were 
conducted. Griffin believes the metabolism is well characterized in 
plants and animals and the pathways of metabolism are very similar to 
those defined for other triazines. The metabolism profile supports the 
use of an analytical enforcement method that accounts for parent 
propazine and its two chloro metabolites, 2-amino-chloro- 6-isopropyl-
amino-s-triazine (G-30033) and 2-chloro-4,6-di-amino-s-triazine (G-
28273) in the raw agricultural commodity (RAC's) of grain sorghum and 
further supports the current tolerance of 0.25 ppm to include the two 
chloro metabolites.
    2. Analytical method. A practical analytical method has been 
submitted, as a part of the sorghum residue study. The method involves 
extraction, evaporation solid phase clean-up

[[Page 36162]]

column and quantitation by high performance liquid chromotography 
(HPLC) equipped with a ultraviolet ray (UV) detector. One aliquot is 
used for assaying for propazine and G-30033 and another aliquot is used 
for quantitating G-27283. The limit of quanitation (LOQ) for propazine 
and each of its chloro metabolites in each raw agricultural commodities 
(RAC) and each chloro residue is 0.05 ppm.
    3. Magnitude of residues. A total of 13 sorghum field residue 
trails were conducted in the major sorghum growing areas of the United 
States. No quantifiable residues of parent or the two chloro 
metabolites were detected in the RAC's of the 13 field residue studies 
when treated at the 1x rate. Only four samples for sorghum forage 
contained residues of G-28273 which were quantifiable and residues 
ranged from 0.05 ppm to 0.087 ppm. The treatment rate for these studies 
exceeded the maximum proposed use rate and the extrapolated range of 
residues for the four samples was 0.024 to 0.069 ppm.
    The RAC's of sorghum are only used as feed for cattle and poultry. 
Only the grain is fed to chickens and there were no chloro residues 
present in grain; therefore, no chloro residues would be expected in 
eggs and poultry products. The level of chloro residues in forage and 
fodder are sufficiently low in the metabolism and residue studies to 
demonstrate that any potential transfer of propazine and its chloro 
metabolites to milk and meat is not expected. For rotational crops, no 
chloro residues were present in root and grain crops when planted more 
than 129 days after treatment. Chloro residues were present in leafy 
vegetables grown in soils with pH values above 7 and under inclimate 
growing conditions. One field sample of wheat forage contained low 
levels of parent propazine but this sample was taken at an interval 
shorter than will be proposed on the label for plant back and, in 
addition, the pH of the soil was above 7.
    An amendment of the current tolerance of 0.25 ppm to include parent 
propazine and its two chloro metabolites, G-30033 and G-28273, is 
proposed for each of the RAC's of grain sorghum. The metabolism and 
field residue results show that chloro residues of propazine should not 
exceed 0.25 ppm in any of the RAC's. Potential transfer of propazine 
and its two chloro metabolites to milk and meat is not expected. 
Therefore, tolerances in milk, meat, poultry and eggs are not required. 
The data show that root and grain crops can be rotated with sorghum 
treated with propazine, but leafy vegetable crops should not be rotated 
with sorghum in soils with pH values above 7.

B. Toxicological Profile

    1. Acute toxicity. A complete battery of acute toxicity studies for 
propazine technical was completed. The acute oral toxicity study 
resulted in a LD50 of greater than 5,050 milligram kilogram 
(mg/kg) for both sexes. The acute dermal toxicity in rabbits resulted 
in an LD50 in either sex of greater than 5,050 mg/kg. The 
acute inhalation study in rats resulted in an LC50 of 
greater than 1.22 mg/l. Propazine was non-irritating to the skin of 
rabbits in the primary dermal irritation study. In the primary eye 
irritation study in rabbits, no irritation was noted. The dermal 
sensitization study in guinea pigs indicated that propazine is not a 
sensitizer. Based on these results, propazine technical is placed in 
toxicity Category III.
    2. Genotoxicity Propazine was positive without activation and 
weakly positive with activation in an in vitro Chinese hamster cell 
point mutation assay. It did not affect DNA repair in rat hepatocytes. 
In in vivo assays, propazine was negative for both production anomalies 
in Chinese hamster somatic cell nuclei in interphase and induction 
structural damage (chromosome aberrations) in mouse spermatogonial 
cells.
    3. Reproductive and developmental toxicity. The potential maternal 
and developmental toxicity of propazine were evaluated in rabbits. 
Propazine technical was suspended in corn oil and administered orally 
by gavage to three groups of 20 artificially inseminated New Zealand 
White rabbits as a single daily dose from gestation days 6-18. In the 
range-finding study, rabbits were dosed at levels of 0, 10, 50, 100, 
200, and 400 milligram kilogram/day (mg/kg/day). Maternal toxicity was 
exhibited by decreased defecation, body weight losses and decreased 
food consumption during the treatment period at 50, 100, 200 and 400 
mg/kg/day. Abortions also occurred at levels of 200 and 400 mg/kg/day. 
Dose levels of 0, 2, 10, and 50 mg/kg/day were selected based on the 
results of this study. In the definitive study, no test article related 
deaths occurred at any dose level tested. The only clinical sign 
observed was decreased defecation in the 50 mg/kg/ day group. 
Inhibition of body weight gain occurred during the first 6 days of 
dosing and inhibition of food consumption occurred throughout the 
treatment period in the 50 mg/kg/day group. No other treatment related 
findings were noted in the dams at any dose level. Intrauterine 
parameters were unaffected by treatment. There were no treatment 
related effects on fetal malformations or developmental variations.
    The data from the developmental toxicity studies on propazine show 
no evidence of a potential for developmental effects (malformations or 
variations) at doses that are not maternally toxic. The no observed 
adverse effect level (NOAEL) for maternal toxicity in rabbits was 10 
mg/kg/day and the NOAEL for developmental toxicity was 50 mg/kg/day.
    4. Subchronic toxicity. No test article related deaths occurred at 
any dose level. Very minimal dermal irritation was noted in the 100 and 
1,000 mg/kg/day females. Body weight gain was slightly inhibited in the 
high dose group during weeks 0-1 (both sexes) and 2-3 (males only). 
There were no treatment related effects on the clinical observations, 
food consumption, hematology and serum chemistry parameters or organ 
weights were observed at any dose level. Macroscopic and microscopic 
examinations revealed no treatment related lesions at any dose level. 
Based on the 21 day dermal study in rats, the NOAEL for systemic 
toxicity was 100 mg/kg/day due to reduced body weight gain at 1,000 mg/
kg/day.
    5. Chronic toxicity. Griffin conclude that the body weight gain and 
survival data clearly indicate that the high dietary concentration of 
1,000 ppm (68 mg/kg/day) for female rats exceeded the maximum tolerance 
dose (MTD), and therefore, the high dose female group should be 
excluded from any risk assessment or weight-of-evidence arguments 
concerning this study. Additionally, the incidence of mammary gland 
tumors in all doses in this study were within the range of current 
laboratory historical control incidences and those reported by the 
breeder, Charles River. No adverse treatment related effects were 
observed at levels below the MTD (100 ppm or lower for females).
    6. Animal metabolism. The absorption, distribution, excretion, and 
metabolism of propazine (ring-UL-14C propazine) was investigated in 
Sprague-Dawley CD rats. One group of rats was administered a single 
oral dose at 1.0 mg/kg (low dose), one group was administered a single 
oral dose at 100 mg/kg (high dose), and a third group was administered 
fourteen consecutive oral daily doses of non-radioactive propazine at 
1.0 mg/kg, followed by a single oral dose of 14C-propazine at 1.0 mg/kg 
(consecutive dose group). A fourth group of animals (3 rats/sex) was 
administered a single oral dose of the vehicle only (corn oil), and 
served as

[[Page 36163]]

controls. Since propazine is not soluble in water, it was not possible 
to include an intravenous dose group. Excretion patterns were very 
similar in all dose groups. Nearly all of the radioactivity 
administered was recovered in the excreta within 24 to 48 hours after 
dosing. The majority of the administered radioactivity was excreted in 
the urine (66.2-70.5%), and this finding shows that the majority of the 
administered dose was bioavailable and rapidly absorbed from the 
gastrointestinal tract. High performance liquid chromotography (HPLC) 
analysis of the urine indicated a similar profile among all dose groups 
and both sexes. The excretion of radioactivity in the feces was 
significantly lower than in the urine (range: 19.9-28.6%) in all dose 
groups and both sexes. Analysis of this radioactivity demonstrated a 
relatively consistent pattern among the various dose groups with 
females containing a quantitatively higher level of the parent 
compound. The recovery of expired radioactivity was shown in a pilot 
study to be negligible (< 0.1%), indicating little or no 14CO2 
production during the metabolism of propazine.
    Seven days post-treatment all animals were sacrificed and the total 
radioactive residue was quantified in bone, brain, fat (visceral), 
gastrointestinal tract (including contents), heart, kidney, liver, 
lung, muscle (thigh), ovary, plasma, red blood cells (RBC), skin, 
spleen, testis, thyroid, uterus, and residual carcass. Highest 
concentrations were found in the RBCs of all dose groups (0.472-0.577 
ppm parent equivalents at 1.0 mg/kg and 44.649-55.287 ppm at 100 mg/
kg). Residue concentration in the remaining tissues ranged from 0.007 
to 0.468 ppm at the low and consecutive dose groups, and from 0.859 to 
13.246 ppm at the high dose. Mean body burdens for the low, high, and 
consecutive dose groups accounted for 10.3, 5.9 and 7.1% of the dose, 
respectively. Material balances were quantitative and accounted for 
102.5, 101.1 and 96.3% of the dose, respectively. Metabolite 
characterization of excreta indicated a biotransformation pathway 
consistent with historical metabolism of alkylated s-triazines. 
Confirmed metabolite identification showed that propazine was 
metabolized via Ndealkylation mechanisms and excreted in urine 
primarily as the G-27283 metabolite (approximately 27% of the total 
dose). Unmetabolized parent propazine was the predominant identified 
compound in the feces (13.8% in the high dose male group). The fact 
that a greater percentage of administered 14C-propazine was found in 
the feces of the high dose group probably indicated some degree of 
saturation of the absorption mechanism. Propazine technical is not 
metabolized to breakdown products which accumulate in sufficient 
quantities that can be reasonably expected to present any chronic 
dietary risk.
    7. Metabolite toxicology. The hydroxy metabolite of atrazine, an 
analog of propazine has been shown not to exhibit carcinogenic effects.
    8. Endocrine disruption. There is no evidence that propazine has 
endocrinemodulation characteristics as demonstrated by the lack of 
endocrine effects in developmental, subchronic and chronic studies.

C. Aggregate Exposure

    1. Dietary exposure--i. Food. A dietary risk exposure study dietary 
risk evaluation system (DRES) for Griffin for the purpose of estimating 
dietary exposure to propazine residues. Grain sorghum is the only 
proposed food or food use of propazine. Therefore, there exists no 
potential for human consumption of crops treated with propazine. 
Sorghum (grain, forage and stover) is, however, fed to livestock. Grain 
is the only sorghum commodity fed to poultry. There are no chloro 
residues, the residues of toxicological concern, in the grain. In turn, 
there is no potential for poultry to be exposed to propazine or related 
residues. Beef and dairy cattle are fed all sorghum commodities: grain, 
forage, stover, and aspirated grain fractions. Therefore, in evaluating 
potential human dietary exposure to propazine, the potential exposure 
via secondary residues in meat and milk must be considered. The total 
chloro residues for a goat dosed at 9.9 ppm in a metabolism study were 
low. Specifically, the highest total residue while the lowest residue 
of < 0.002 ppm was observed in kidney.
    These tissues to feed ratios can then be combined with the worst-
case diets derived from a sorghum only ration which includes propazine 
residues at the tolerance level of 0.25 ppm. (It should be noted that 
this worst-case diet is not a ration that would be fed to cattle). The 
results of this indicate that even under theoretically worst-case 
conditions all meat and milk residues are extremely low (all less than 
0.01 ppm; the LOQ in plant matrices is 0.05 ppm). In turn, there is no 
potential for dietary exposure to propazine via secondary residues in 
meat and milk. Therefore, tolerances for meat and milk are not required 
for propazine.
    ii. Drinking water. Griffin conclude that environmental fate and 
behavior studies, including aerobic soil metabolism, field lysimeter, 
and long term soil dissipation, indicate little potential for propazine 
to reach surface or ground water from its proposed use on grain 
sorghum. Griffin concludes that, there is little potential for dietary 
exposure to propazine residues in water exists.
    2. Non-dietary exposure. There are no residential uses for 
propazine in the United States, therefore, there is no potential for 
residential exposure.

D. Cumulative Effects

    Because of the benefits of propazine, most of the propazine use on 
sorghum will be substituted for other triazines and since the proposed 
use rate is lower than the other triazines the cumulative will not 
increase and could possibly be reduced as a result of registering 
propazine for use on grain sorghum.

E. Safety Determination

    The reference dose (RfD) is based on the rat chronic study. Using 
the (no adverse effect level (NOAEL) of 5 mg/kg/day in this study and 
an additional uncertainty factor (UF) of 300 (100 intraspecies and 
interspecies uncertainty factor plus an additional uncertainty factor 
of 3X for lack of a chronic study in dogs) an RfD of 0.02 mg/kg/day was 
established as the chronic dietary endpoint.
    1. U.S. population. In the DRES analysis referenced above, it was 
determined that there is no potential exposure to propazine via 
dietary, water, or nonoccupational routes.
    2. Infants and children. In assessing the potential for additional 
sensitivity of infants and children to residues of propazine, the 
available developmental toxicity study and the potential for endocrine 
modulation by propazine were considered. The data from the 
developmental toxicity studies on propazine show no evidence of a 
potential for developmental effects (malformations or variations) at 
doses that are not maternally toxic. The developmental NOAELs and 
lowest observed effect levels (LOAELs) were at higher dose levels (less 
toxic), indicating no increase in susceptibility of developing 
organisms. No evidence of endocrine effects were noted in any study. It 
is therefore concluded that propazine poses no additional risk for 
infants and children and no additional uncertainty factor is warranted. 
Federal food, drug and cosmetic act (FFDCA) section 408 provides that 
an additional safety factor for infants and children may be applied in 
the case of threshold effects. Since, as discussed in the previous 
section, the toxicology studies do not indicate that young animals are

[[Page 36164]]

any more susceptible than adult animals and the fact that the current 
RfD calculated from the NOAEL from the rat chronic study already 
incorporates a 300x uncertainty factor, Griffin believes that an 
adequate margin of safety is, therefore, provided by the RfD 
established by EPA. There is no evidence that propazine has endocrine-
modulation characteristics as demonstrated by the lack of endocrine 
effects in developmental, subchronic, and chronic studies. There is no 
potential exposure to propazine via dietary, water, or non-occupational 
routes based on the proposed use on grain sorghum. No additional 
uncertainty factor for infants and children is warranted based on the 
completeness and reliability of the data base, the demonstrated lack of 
increased risk to developing organisms, and the lack of endocrine-
modulating effects.

F. International Tolerances

    There are no Codex Alimentarius Commission (CODEX) maximum residue 
levels (MRLs) established for residues of propazine and its chloro 
metabolites in or on raw agricultural commodities.

[FR Doc. 05-12015 Filed 6-21-05; 8:45 am]
BILLING CODE 6560-50-S