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Chlorpyrifos - Pesticide Tolerances and Food Additive Regulations 4/93

40 CFR Parts 180 and 185
[PP 3F2884 and 3F2947 and FAP 3H5396 and 3H5411/R1191; FRL-4579-8]
RIN No. 2070-AB78
Pesticide Tolerances and Food Additive Regulations for Chlorpyrifos
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.

------------------------------------------------------------
SUMMARY: These regulations revise the tolerances for residues
of the insecticide chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-
2-pyridyl) phosphorothioate] in or on various raw agricultural
commodities and processed food commodities. The regulations
also establish tolerances for residues for chlorpyrifos in or
on the raw agricultural commodities wheat grain, wheat straw,
and wheat forage, and the processed food commodity milling fractions
(except flour) of wheat. These regulations to revise maximum
permissible levels for residues and establish new levels for
residues of the insecticide were requested in petitions submitted
by DowElanco.

EFFECTIVE DATE: These regulations became effective on April
1, 1993.

ADDRESSES: Written objections, identified by the document control
numbers [FP 3F2884 and 3F2947 and FAP 3H5396 and 3H5411/R1191],
may be submitted to: Hearing Clerk (A-110), Environmental Protection
Agency, Rm. 3708, 401 M St., SW., Washington, DC 20460.

FOR FURTHER INFORMATION CONTACT: By mail: Dennis H. Edwards,
Jr., Product Manager (PM) 19, Registration Division (H7505C),
Environmental Protection Agency, 401 M St., Sw., Washington,
DC 20460. Office location and telephone number: Rm. 207, CM
#2, 1921 Jefferson Davis Hwy., Arlington, VA 22202, (703)-305-
6386.
SUPPLEMENTARY INFORMATION: EPA has issued notices in the Federal
Register announcing that DowElanco has submitted pesticide petitions
to EPA proposing to amend 40 CFR 180.342 by revising tolerances
under section 408 of the Federal Food, Drug, and Cosmetic Act
(FFDCA), 21 U.S.C. 346a, for the combined residues of the insecticide
chlorpyrifos and its metabolite 3,5,6-trichloro-2-pyridinol
(TCP) in or on various raw agricultural commodities and food
additive petitions proposing to amend 40 CFR 185.1000 by revising
tolerances under section 409 of the FFDCA, 21 U.S.C. 348, for
the combined residues of the insecticide chlorpyrifos and its
metabolite in or on various processed food commodities. The
proposed revision included a change in the form of the tolerance
expression. The existing tolerance was expressed as a numerical
value indicating the total concentration of chlorpyrifos and
the metabolite TCP. The proposed revision continued to indicate
a total, but also included a separate statement that the concentration
of the parent chlorpyrifos in the total must not exceed a specified
value. The petitioner subsequently amended the petition by proposing
to remove the metabolite TCP from the tolerance expression,
thus expressing the tolerance for various commodities in terms
of the parent chlorpyrifos only. By removing TCP from the tolerance
expression for chlorpyrifos for various commodities, the petitioner
intends to more accurately reflect the level of residues of
toxicological concern that are anticipated on treated commodities
and the impact of this exposure calculation on the determination
of whether the Reference Dose (RfD) or Acceptable Daily Intake
(ADI) have been exceeded.
   The specific publication dates of the petitions were as follows:
(1) PP 3F2884 and FAP 3H5396 appeared in the Federal Register
of June 22, 1983 (48 FR 28545); (2) PP 3F2947 and FAP 3H5411
appeared in the Federal Register of September 29, 1983 (48 FR
44643).
   There were no comments or requests for a referral to an advisory
committee received in response to the notices of filing. The
data submitted in the petitions and other relevant material
have been evaluated. The pesticide is considered useful for
the purpose for which the tolerances are sought and capable
of achieving its intended physical or technical effect. The
toxicological data considered in support of the proposed tolerances
include the following:
   1. A 2-year dog feeding study with a no-observed-effect level
(NOEL) for systemic effects of 1.0 milligram (mg)/ kilogram
(kg)/day and lowest effect
level (LEL) (increased liver weight)
of 3.0 mg/kg/day. The NOELs for cholinesterase (ChE) inhibition
were as follows: 0.01 mg/kg/day for plasma, 0.1 mg/kg/day for
red blood cells, and 1.0 mg/kg/day for brain cells. Levels tested
were 0, 0.01, 0.03, 0.1, 1.0, and 3 mg/kg/day.
   2. A voluntary human study with ChE NOEL of 0.03 mg/kg/day
(based on 20 days of exposure at this level).
   3. A 2-year mouse chronic toxicity/carcinogenicity study
with a NOEL of 15 ppm for systemic effects (equivalent to 2.25
mg/kg/day) and no carcinogenic effects observed under the conditions
of the study at all levels tested (0, 0.5, 5, and 15 ppm, equivalent
to 0.075, 0.75, and 2.25 mg/kg/day).
   4. A 2-year rat feeding/carcinogenicity study with ChE NOEL
of 0.1 and LEL of 1.0 mg/kg/day (based on decreased plasma and
brain ChE activity), and a systemic NOEL of 1.0 mg/kg/day and
LEL of 10 mg/kg/day (based on decreased erythrocyte and hemoglobin
values and increased platelet count during the first year).
There were no observed carcinogenic effects at the levels tested
(0.05, 0.1, 1.0, and 10 mg/kg/day) under the conditions of the
study.
   5. A three-generation reproduction study in rats with no
reproductive effects observed at the dietary levels tested (0,
0.1, 0.3, and 1.0 mg/kg/day).
   6. Two rat developmental toxicity studies: one negative for
developmental toxicity at all dose levels (levels tested were
0.1, 3.0, and 15.0 mg/kg/day); and one with maternal and developmental
NOELs of 2.5 mg/kg/day (levels tested, by gavage, were 0, 0.5,
2.5, and 15 mg/kg/day).
   7. A mouse developmental toxicity study with a teratogenic
NOEL greater than 25 mg/kg/day (highest dose tested) and a developmental
fetotoxic NOEL of 10 mg/kg/day and LEL of 25 mg/kg/day (decreased
fetal length and increased skeletal variants).
   8. A developmental toxicity study in rabbits with maternal
and developmental NOELs of 81 mg/kg/day, and maternal and developmental
LELs of 140 mg/kg/day (based on maternal decreased food consumption
on gestation day 15 to 19, and body weight loss during the dosing
period followed by a compensatory weight gain; and based on
a slight reduction in fetal weights and crown-rump lengths,
and fetal increased incidence of unossified fifth sternebrae
and/or xiphisternum). Levels tested were 0, 1, 9, 81, and 140
mg/kg/day.
   9. An acute delayed neurotoxicity study in the hen that was
negative at 50 and 100 mg/kg/day.
   10. Several mutagenicity studies which were all negative.
These include an Ames assay, two Chinese hamster ovary cell
mutation assays, a micronucleus assay for chromosomal aberration,
an in vitro chromosomal aberration assay with and without enzymatic
activation, and an unscheduled DNA synthesis assay.
   11. A general metabolism study in rats shows that the major
metabolite of chlorpyrifos is 3,5,6-trichloro-2-pyridinol (TCP).
The studies listed below were conducted to demonstrate that
TCP is less toxic than chlorpyrifos and is not a ChE inhibitor.
   a. A 90-day rat feeding study with a systemic NOEL of 30
mg/kg/day. Levels tested were 0, 10, 30, and 100 mg/kg/day.
   b. A rat developmental toxicity study with no developmental
toxicity observed at the dosages tested (0, 50, 100, and 150
mg/kg/day).
   c. Mutagenicity studies (including an Ames assay and an unscheduled
DNA synthesis assay) were negative for mutagenic effects.
   Based on the above studies, the Agency has concluded that
the TCP metabolite is not of toxicological concern.
   Regarding tolerances for residues of chlorpyrifos in or on
the various raw agricultural commodities and processed food
commodities, the reference dose (RfD) based on the human voluntary
ChE study (ChE NOEL of 0.03 mg/kg/day) and using a 10-fold uncertainty
factor is calculated to be 0.003 mg/kg of body weight/day. Tolerances
for food uses appear in 40 CFR 180.342 and 40 CFR 185.1000.
The Dietary Risk Exposure Section (DRES) chronic dietary exposure
analysis made use, when justified and appropriate, of anticipated
residues rather than published tolerance values, and data regarding
percent crop treated (when less than 100 percent). The TCP metabolite
was removed from tolerance expressions. The anticipated residue
contribution (ARC) for chlorpyrifos is estimated to be 0.000792
mg/kg of body weight/day for the overall U.S. population. This
represents 26.4 percent of the RfD. (Before removal of the TCP
metabolite from the tolerance expression, the ARC was 0.001430
mg/kg of body weight/day, 47.7 percent of the RfD.) The population
subgroups with the highest estimated ARCs are nonnursing infants,
less than 1 year old, with an ARC of 0.002095 mg/kg of body
weight/day, 69.8 percent of the RfD (before removal of TCP the
ARC was 0.003580 mg/kg of body weight/day, 119.3 percent of
the RfD); children, 1 to 6 years old, with an ARC of 0.001780
mg/kg of body weight/day, 59.3 percent of the RfD (before removal
of TCP the ARC was 0.003132 mg/kg of body weight/day, 104.4
percent of the RfD); and children, 7 to 12 years old, with an
ARC of 0.001184 mg/kg of body weight/day, 39.5 percent of the
RfD (before removal of TCP the ARC was 0.002123 mg/kg/day, 70.8
percent of the RfD).
   Regarding tolerances for residues of chlorpyrifos in or on
the raw agricultural commodities wheat grain, wheat straw, and
wheat forage, and the processed food commodity milling fractions
(except flour) of wheat, the reference dose (RfD) based on the
human voluntary ChE study (ChE NOEL of 0.03 mg/kg/day) and using
a 10-fold uncertainty factor is calculated to be 0.003 mg/kg
of body weight/day. The Dietary Risk Exposure Section (DRES)
chronic dietary exposure analysis made use, when justified and
appropriate, of anticipated residues rather than published tolerance
values, and data regarding percent crop treated (when less than
100 percent). The TCP metabolite was not included in tolerance
expressions. The anticipated residue contribution (ARC) for
chlorpyrifos was estimated to be 0.000792 mg/kg of body weight/day
for the overall U.S. population. This represents 26.4 percent
of the RfD. The addition of tolerances for wheat grain, wheat
straw, and wheat forage raises the ARC to 0.000811 mg/kg of
body weight/day. This represents 27.0 percent of the RfD. The
population subgroups with the highest ARCs are nonnursing infants,
less than 1 year old, with an ARC of 0.002108 mg/kg of body
weight/day (70.3 percent of the RfD); children, 1 to 6 years
old, with an ARC of 0.001823 mg/kg of body weight/day (60.8
percent of the RfD); and children, 7 to 12 years old, with an
ARC of 0.001214 mg/kg of body weight/day (40.4 percent of the
RfD).
   The data submitted in the petitions and other relevant material
have been evaluated. The pesticide is considered useful for
the purpose for which the tolerances are sought and capable
of achieving its intended physical or technical effect. A conditional
registration for the use of chlorpyrifos on wheat is being issued,
although the Agency has some concerns about the potential for
adverse effects on both avian and aquatic species. Risk mitigation
measures are being imposed to reduce that potential. In order
to determine if the risk mitigation measures are effective,
the Agency as a condition of registration will impose both incident
and residue monitoring requirements. Monitoring will not commence,
however, until the Agency is able to provided additional guidance.
   Adequate gas chromatographic analytical methods are available
in the Pesticide Analytical Manual, Vol. II (PAM II), for enforcement
purposes. There are currently no actions pending against continued
registration of this chemical.
   Based on the above information considered by the Agency,
the tolerances established by amending 40 CFR 180.342 would
protect the public health and use of the pesticide in accordance
with amended 40 CFR 185.1000 would be safe. Therefore, the tolerances
are established as set forth below.
   Any person adversely affected by this regulation may, within
30 days after publication of this document in the Federal Register,
file written objections with the Hearing Clerk, at the address
given above. 40 CFR 178.20. The objections submitted must specify
the provisions of the regulation deemed objectionable and the
grounds for the objections. 40 CFR 178.25. Each objection must
be accompanied by the fee prescribed by 40 CFR 180.33(i). If
a hearing is requested, the objections must include a statement
of the factual issue(s) on which a hearing is requested, the
requestor's contentions on each such issue, and a summary of
any evidence relied upon by the objector. 40 CFR 178.27. A request
for a hearing will be granted if the Administrator determines
that the material submitted shows the following: There is a
genuine and substantial issue of fact; there is a reasonable
possibility that available evidence identified by the requestor
would, if established, resolve one or more of such issues in
favor of the requestor, taking into account uncontested claims
or facts to the contrary; and resolution of the factual issue(s)
in the manner sought by the requestor would be adequate to justify
the action requested. 40 CFR 178.32.
   The Office of Management and Budget has exempted this rule
from the requirements of section 3 of Executive Order 12291.
Pursuant to the requirements of the Regulatory Flexibility Act
(Pub. L. 96-54, 94 Stat. 1164, 5 U.S.C. 601-612), the Administrator
has determined that regulations establishing new tolerances
or raising tolerance levels or establishing exemptions from
tolerance requirements do not have a significant economic impact
on a substantial number of small entities. A certification statement
to this effect was published in the Federal Register of May
4, 1981 (46 FR 24950).

List of Subjects in 40 CFR Parts 180 and 185

   Administrative practice and procedure, Agricultural commodities,
Food additives, Pesticides and pests, Reporting and recordkeeping
requirements.

Dated: April 1, 1993.

Daniel M. Barolo,
Acting Director, Office of Pesticide Programs.

PART 180-[AMENDED]

   Therefore, chapter I of title 40 of the Code of Federal Regulations
is amended as follows:
   1. In part 180:
   a. The authority citation for part 180 continues to read
as follows:

   Authority: 21 U.S.C. 346a and 371.

   b. In 180.342, paragraph (a) is amended by revising the
table therein, and paragraph (c) is amended by revising the
table therein, to read as follows:

180.342   Chlorpyrifos; tolerances for residues.

   (a) * * *

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Commodity                              Parts per
                                                                   million
------------------------------------------------------------------------------

Almonds........................................................          0.2
Almonds, hulls.................................................         12.0
Apples.........................................................          1.5
Beans, lima....................................................          0.05
Beans, lima, forage............................................          1.0
Beans, snap....................................................          0.05
Beans, snap, forage............................................          1.0
Beets, sugar, roots............................................          1.0
Beets, sugar, tops.............................................          8.0
Blueberries....................................................    2 ppm (of
                                                                    which no
                                                                 more than 1
                                                                 ppm is chl
                                                                 orpyrifos)
Citrus fruits..................................................          1.0
Corn, fresh (inc. sweet K-CWHR)................................          0.1
Cranberries....................................................          1.0
Kiwifruit......................................................          2.0
Mushrooms......................................................          0.1
Onions (dry bulb)..............................................          0.5
Peppers........................................................          1.0
Seed and pod vegetables .......................................          0.1
Sorghum, fodder................................................          6.0
Sorghum, forage ...............................................          1.5
Sorghum, grain.................................................          0.75
Sunflower, seeds...............................................          0.25
Tomatoes.......................................................          0.5
Tree nuts......................................................          0.2
Vegetables, leafy, Brassica (cole).............................         12.0
Walnuts........................................................          0.2
------------------------------------------------------------------------------
  1 Of which no more than 1.0 ppm is chlorpyrifos.

*     *     *     *     *
   (c) * * *

------------------------------------------------------------------------------
Commodity                              Parts per
                                                                   million
------------------------------------------------------------------------------

Alfalfa, forage................................................            3
Alfalfa, hay...................................................           13
Bananas, whole.................................................            0.1
Bananas, pulp with peel removed................................            0.01
Bean, forage...................................................            0.7
Broccoli.......................................................            1
Brussels sprouts...............................................            1
Cabbage........................................................            1
Caneberries....................................................            1.0
Cattle, fat....................................................            0.3
Cattle, meat and meat byproducts...............................            0.05
Cauliflower....................................................            1
Cherries.......................................................            1
Chinese cabbage................................................            1
Corn, field, grain.............................................            0.05
Corn, forage and fodder........................................            8
Cottonseed.....................................................            0.2
Cucumbers......................................................            0.05
Eggs...........................................................            0.01
Figs...........................................................            0.01
Goats, fat.....................................................            0.2
Goats, meat and meat byproducts................................            0.05
Hogs, fat......................................................            0.2
Hogs, meat and meat byproducts.................................            0.05
Horses, meat, fat, and meat byproducts.........................            0.25
Legume vegetables, succulent or dried (except soybeans)........            0.05
Milk, fat......................................................            0.25
Milk, whole....................................................            0.01
Mint, hay......................................................            0.8
Nectarines.....................................................            0.01
Peaches........................................................            0.01
Pea forage.....................................................            0.7
Peanut hulls...................................................            2
Peanuts........................................................            0.2
Pears..........................................................            0.01
Plums (fresh prunes)...........................................            0.01
Poultry, meat, fat, and meat byproducts (inc. turkeys).........            0.1
Pumpkins.......................................................            0.05
Radishes.......................................................            2
Rutabagas......................................................            0.5
Sheep, fat.....................................................            0.2
Sheep, meat and meat byproducts................................            0.05
Soybean grain..................................................            0.3
Soybean forage.................................................            0.7
Strawberries...................................................            0.2
Sweet potatoes.................................................            0.05
Turnip greens..................................................            0.3
Turnips........................................................            1
Wheat, grain...................................................            0.5
Wheat, straw...................................................            6
Wheat, forage..................................................            3
------------------------------------------------------------------------------

*     *     *     *     *

PART 185-[AMENDED]

   2. In part 185:
   a. The authority citation for part 185 continues to read
as follows:

   Authority: 21 U.S.C. 348.
   b. In 185.1000, paragraph (a) is amended by revising the
table therein, and new paragraph (d) is added, to read as follows:

185.1000   Chlorpyrifos.

   (a) * * *

------------------------------------------------------------------------------
                             Foods                                Parts per
                                                                   million
------------------------------------------------------------------------------

Citrus oil.....................................................         25.0
Corn oil.......................................................          3.0
------------------------------------------------------------------------------

*     *     *     *     *
   (d) Tolerances are established for residues of the insecticide
chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridyl) phosphorothioate]
resulting from application of the insecticide to growing crops
as follows:

------------------------------------------------------------------------------
                             Foods                                Parts per
                                                                   million
------------------------------------------------------------------------------

Milling fractions (except flour) of wheat......................          1.5
Mint oil.......................................................          8
Peanut oil.....................................................          0.4
------------------------------------------------------------------------------

[FR Doc. 93-8572 Filed 4-13-93; 8:45 am]