Federal Register / Vol. 75, No. 101 / Wednesday, May 26, 2010 / Rules and Regulations 29435 

with Indian Tribal Governments (65 FR 

67249, November 9, 2000) do not apply 

to this final rule. In addition, this final 

rule does not impose any enforceable 

duty or contain any unfunded mandate 

as described under Title II of the 

Unfunded Mandates Reform Act of 1995 

(UMRA) (Public Law 104–4). 

This action does not involve any 

technical standards that would require 

Agency consideration of voluntary 

consensus standards pursuant to section 

12(d) of the National Technology 

Transfer and Advancement Act of 1995 

(NTTAA), Public Law 104–113, section 

12(d) (15 U.S.C. 272 note). 

X. Congressional Review Act 

The Congressional Review Act, 5 

U.S.C. 801 et seq., generally provides 

that before a rule may take effect, the 

agency promulgating the rule must 

submit a rule report to each House of 

the Congress and to the Comptroller 

General of the United States. EPA will 

submit a report containing this rule and 

other required information to the U.S. 

Senate, the U.S. House of 

Representatives, and the Comptroller 

General of the United States prior to 

publication of this final rule in the 

Federal Register. This final rule is not 

a ‘‘major rule’’ as defined by 5 U.S.C. 

804(2). 

List of Subjects in 40 CFR Part 174 

Environmental protection, 

Administrative practice and procedure, 

Agricultural commodities, Pesticides 

and pests, Reporting and recordkeeping 

requirements. 

Dated: May 7, 2010. 

Steven Bradbury, 

Acting Director, Office of Pesticide Programs. 

■ Therefore, 40 CFR chapter I is 

amended as follows: 

PART 174—[AMENDED] 

■ 1. The authority citation for part 174 

continues to read as follows: 

Authority: 21 U.S.C. 321(q), 346a and 371. 

■ 2. Section 174.531 is added to subpart 

W to read as follows: 

§174.531 Coat protein of plum pox virus; 

exemption from the requirement of a 

tolerance. 

Residues of the coat protein of plum 

pox virus in or on the food commodities 

of fruit, stone, Group 12; and almond, 

are exempt from the requirement of a 

tolerance in these food commodities 

when expressed by the plantincorporated protectant, coat protein 

gene of plum pox virus, and used in 

accordance with good agricultural 

practices. 

[FR Doc. 2010–12579 Filed 5–25–10; 8:45 am] 

BILLING CODE 6560–50–S 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 180 

[EPA–HQ–OPP–2009–0920; FRL–8827–7] 

Diquat Dibromide; Pesticide 

Tolerances 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Final rule. 

SUMMARY: This regulation establishes 

tolerances for residues of diquat, 

derived from applications of diquat 

dibromide, in or on canola meal and 

canola seed. Syngenta Crop Protection, 

Inc. requested these tolerances under 

the Federal Food, Drug, and Cosmetic 

Act (FFDCA). This regulation also 

corrects minor errors in the regulations 

for diquat at 40 CFR 180.266. 

DATES: This regulation is effective May 

26, 2010. Objections and requests for 

hearings must be received on or before 

July 26, 2010, and must be filed in 

accordance with the instructions 

provided in 40 CFR part 178 (see also 

Unit I.C. of the SUPPLEMENTARY

INFORMATION). 

ADDRESSES: EPA has established a 

docket for this action under docket 

identification (ID) number EPA–HQ– 

OPP–2009–0920. All documents in the 

docket are listed in the docket index 

available at http://www.regulations.gov. 

Although listed in the index, some 

information is not publicly available, 

e.g., Confidential Business Information 

(CBI) or other information whose 

disclosure is restricted by statute. 

Certain other material, such as 

copyrighted material, is not placed on 

the Internet and will be publicly 

available only in hard copy form. 

Publicly available docket materials are 

available in the electronic docket at 

http://www.regulations.gov, or, if only 

available in hard copy, at the OPP 

Regulatory Public Docket in Rm. S– 

4400, One Potomac Yard (South Bldg.), 

2777 S. Crystal Dr., Arlington, VA. The 

Docket Facility is open from 8:30 a.m. 

to 4 p.m., Monday through Friday, 

excluding legal holidays. The Docket 

Facility telephone number is (703) 305– 

5805. 

FOR FURTHER INFORMATION CONTACT: 

Susan Stanton, Registration Division 

(7505P), Office of Pesticide Programs, 

Environmental Protection Agency, 1200 

Pennsylvania Ave., NW., Washington, 

DC 20460–0001; telephone number: 

(703) 305–5218; e-mail address: 

stanton.susan@epa.gov. 

SUPPLEMENTARY INFORMATION: 

I. General Information 

A. Does this Action Apply to Me? 

You may be potentially affected by 

this action if you are an agricultural 

producer, food manufacturer, or 

pesticide manufacturer. Potentially 

affected entities may include, but are 

not limited to those engaged in the 

following activities: 

• Crop production (NAICS code 111). 

• Animal production (NAICS code 

112). 

• Food manufacturing (NAICS code 

311). 

• Pesticide manufacturing (NAICS 

code 32532). 

This listing is not intended to be 

exhaustive, but rather to provide 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 Electronic Access to 

Other Related Information? 

You may access a frequently updated 

electronic version of EPA’s tolerance 

regulations at 40 CFR part 180 through 

the Government Printing Office’s e-CFR 

site at http://www.gpoaccess.gov/ecfr. 

To access the harmonized test 

guidelines referenced in this document 

electronically, please go to http:// 

www.epa.gov/oppts and select ‘‘Test 

Methods and Guidelines.’’ 

C. How Can I File an Objection or 

Hearing Request? 

Under FFDCA section 408(g), 21 

U.S.C. 346a, any person may file an 

objection to any aspect of this regulation 

and may also request a hearing on those 

objections. You must file your objection 

or request a hearing on this regulation 

in accordance with the instructions 

provided in 40 CFR part 178. To ensure 

proper receipt by EPA, you must 

identify docket ID number EPA–HQ– 

OPP–2009–0920 in the subject line on 

the first page of your submission. All 

objections and requests for a hearing 

must be in writing, and must be 

received by the Hearing Clerk on or 


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29436 Federal Register / Vol. 75, No. 101 / Wednesday, May 26, 2010 / Rules and Regulations 

before July 26, 2010. Addresses for mail 

and hand delivery of objections and 

hearing requests are provided in 40 CFR 

178.25(b). 

In addition to filing an objection or 

hearing request with the Hearing Clerk 

as described in 40 CFR part 178, please 

submit a copy of the filing that does not 

contain any CBI for inclusion in the 

public docket. Information not marked 

confidential pursuant to 40 CFR part 2 

may be disclosed publicly by EPA 

without prior notice. Submit a copy of 

your non-CBI objection or hearing 

request, identified by docket ID number 

EPA–HQ–OPP–2009–0920, by one of 

the following methods: 

• Federal eRulemaking Portal: http:// 

www.regulations.gov. Follow the on-line 

instructions for submitting comments. 

• Mail: Office of Pesticide Programs 

(OPP) Regulatory Public Docket (7502P), 

Environmental Protection Agency, 1200 

Pennsylvania Ave., NW., Washington, 

DC 20460–0001. 

• Delivery: OPP Regulatory Public 

Docket (7502P), Environmental 

Protection Agency, Rm. S–4400, One 

Potomac Yard (South Bldg.), 2777 S. 

Crystal Dr., Arlington, VA. Deliveries 

are only accepted during the Docket 

Facility’s normal hours of operation 

(8:30 a.m. to 4 p.m., Monday through 

Friday, excluding legal holidays). 

Special arrangements should be made 

for deliveries of boxed information. The 

Docket Facility telephone number is 

(703) 305–5805. 

II. Summary of Petitioned-For 

Tolerance 

In the Federal Register of February 4, 

2010 (75 FR 5793) (FRL–8807–5), EPA 

issued a notice pursuant to section 

408(d)(3) of FFDCA, 21 U.S.C. 

346a(d)(3), announcing the filing of a 

pesticide petition (PP 9F7639) by 

Syngenta Crop Protection, Inc., P.O Box 

18300, Greensboro, NC 27419. The 

petition requested that 40 CFR 180.226 

be amended by establishing tolerances 

for residues of the herbicide diquat, 6,7- 

dihydrodipyrido(1,2-a:2’1’- 

c)pyrazinediium, derived from 

application of the dibromide salt and 

calculated as the cation, in or on canola, 

meal at 3.0 parts per million (ppm); and 

canola, seed at 1.0 ppm. That notice 

referenced a summary of the petition 

prepared by Sygenta Crop Protection, 

Inc., the registrant, which is available in 

the docket, http://www.regulations.gov. 

There were no comments received in 

response to the notice of filing. 

Based upon review of the data 

supporting the petition, EPA has 

increased the tolerance levels for canola, 

meal and canola, seed to 6.0 ppm and 

2.0 ppm, respectively. The reason for 

these changes is explained in Unit IV.C. 

III. Aggregate Risk Assessment and 

Determination of Safety 

Section 408(b)(2)(A)(i) of FFDCA 

allows EPA to establish a tolerance (the 

legal limit for a pesticide chemical 

residue in or on a food) only if EPA 

determines that the tolerance is ‘‘safe.’’ 

Section 408(b)(2)(A)(ii) of FFDCA 

defines ‘‘safe’’ to mean that ‘‘there is a 

reasonable certainty that no harm will 

result from aggregate exposure to the 

pesticide chemical residue, including 

all anticipated dietary exposures and all 

other exposures for which there is 

reliable information.’’ This includes 

exposure through drinking water and in 

residential settings, but does not include 

occupational exposure. Section 

408(b)(2)(C) of FFDCA requires EPA to 

give special consideration to exposure 

of infants and children to the pesticide 

chemical residue in establishing a 

tolerance and to ‘‘ensure that there is a 

reasonable certainty that no harm will 

result to infants and children from 

aggregate exposure to the pesticide 

chemical residue. . . .’’ 

Consistent with section 408(b)(2)(D) 

of FFDCA, and the factors specified in 

section 408(b)(2)(D) of FFDCA, EPA has 

reviewed the available scientific data 

and other relevant information in 

support of this action. EPA has 

sufficient data to assess the hazards of 

and to make a determination on 

aggregate exposure for diquat dibromide 

including exposure resulting from the 

tolerances established by this action. 

EPA’s assessment of exposures and risks 

associated with diquat dibromide 

follows. 

A. Toxicological Profile 

EPA has evaluated the available 

toxicity data and considered its validity, 

completeness, and reliability as well as 

the relationship of the results of the 

studies to human risk. EPA has also 

considered available information 

concerning the variability of the 

sensitivities of major identifiable 

subgroups of consumers, including 

infants and children. 

Diquat dibromide exhibits low acute 

toxicity via the oral and inhalation 

routes of exposure but is moderately to 

severely toxic via the dermal route of 

exposure. Diquat dibromide is not a skin 

irritant nor a dermal sensitizer, but it is 

considered a moderate to severe eye 

irritant. 

Subchronic and chronic studies in 

several species indicate multiple target 

sites for diquat dibromide toxicity. In 

subchronic dermal exposure studies in 

rats, diquat dibromide showed evidence 

of severe systemic toxicity, including 

high mortality and clinical signs. In a 

subchronic inhalation study in rats, the 

lung was determined to be the primary 

target site for inhalation toxicity. 

Chronic feeding studies in dogs, rats, 

mice, and rabbits indicate that target 

sites include the eyes and kidneys in 

both males and females and the adrenals 

and epididymides in males. There was 

no evidence of neurotoxicity in acute 

and subchronic studies in rats and no 

evidence of endocrine disruption or 

immunotoxicity in the toxicology 

studies available for diquat dibromide. 

In accordance with the 1986 Guidelines 

for Carcinogen Risk Assessment, diquat 

dibromide was classified in Group E 

(evidence of non-carcinogenicity to 

humans), based on a lack of evidence of 

carcinogenicity in acceptable studies in 

rats and mice and a lack of concern for 

mutagenicity. 

There was no evidence of increased 

quantitative or qualitative susceptibility 

of in utero animals or of offspring in 

developmental toxicity studies in mice, 

rabbits, and rats or in the 2–generation 

reproduction study in rats. Effects in the 

offspring were observed only at or above 

dose levels which resulted in parental 

toxicity. 

Specific information on the studies 

received and the nature of the adverse 

effects caused by diquat dibromide as 

well as the no-observed-adverse-effectlevel (NOAEL) and the lowest-observedadverse-effect-level (LOAEL) from the 

toxicity studies can be found at http:// 

www.regulations.gov in the document 

‘‘Diquat Dibromide: HED Risk 

Assessment for Tolerance Reassessment 

Eligibility Document (TRED.),’’ p. 10 in 

docket ID number EPA–HQ–OPP–2010– 

0920. 

B. Toxicological Points of Departure/ 

Levels of Concern 

Once a pesticide’s toxicological 

profile is determined, EPA identifies 

toxicological points of departure (POD) 

and levels of concern to use in 

evaluating the risk posed by human 

exposure to the pesticide. For hazards 

that have a threshold below which there 

is no appreciable risk, the toxicological 

POD is used as the basis for derivation 

of reference values for risk assessment. 

PODs are developed based on a careful 

analysis of the doses in each 

toxicological study to determine the 

dose at which no adverse effects are 

observed (the NOAEL) and the lowest 

dose at which adverse effects of concern 

are identified (the LOAEL). Uncertainty/ 

safety factors are used in conjunction 

with the POD to calculate a safe 

exposure level generally referred to as a 

population-adjusted dose (PAD) or a 


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Federal Register / Vol. 75, No. 101 / Wednesday, May 26, 2010 / Rules and Regulations 29437 

reference dose (RfD) and a safe margin 

of exposure (MOE). For non-threshold 

risks, the Agency assumes that any 

amount of exposure will lead to some 

degree of risk. Thus, the Agency 

estimates risk in terms of the probability 

of an occurrence of the adverse effect 

expected in a lifetime. For more 

information on the general principles 

EPA uses in risk characterization and a 

complete description of the risk 

assessment process, see http:// 

www.epa.gov/pesticides/factsheets/ 

riskassess.htm. 

A summary of the toxicological 

endpoints for diquat dibromide used for 

human risk assessment can be found at 

http://www.regulations.gov in the 

document ‘‘Diquat Dibromide: Human 

Health Risk Assessment for the Section 

18 Use on Canola in Oklahoma and 

Kentucky,’’ p. 3 in docket ID number 

EPA–HQ–OPP–2010–0920. 

C. Exposure Assessment 

1. Dietary exposure from food and 

feed uses. In evaluating dietary 

exposure to diquat dibromide, EPA 

considered exposure under the 

petitioned-for tolerances as well as all 

existing diquat dibromide tolerances in 

40 CFR 180.226. EPA assessed dietary 

exposures from diquat dibromide in 

food as follows: 

i. Acute exposure. Quantitative acute 

dietary exposure and risk assessments 

are performed for a food-use pesticide, 

if a toxicological study has indicated the 

possibility of an effect of concern 

occurring as a result of a 1–day or single 

exposure. 

Such effects were identified for diquat 

dibromide. In the acute neurotoxicity 

study in rats, clinical signs of systemic 

toxicity (e.g., piloerection, diarrhea, 

urinary incontinence, upward curvature 

of the spine, subdued behavior) and 

decreased body-weight gains were 

observed after a single dose. In 

estimating acute dietary exposure, EPA 

used food consumption information 

from the United States Department of 

Agriculture (USDA) 1994–1996 and 

1998 Nationwide Continuing Surveys of 

Food Intake by Individuals (CSFII). As 

to residue levels in food, EPA assumed 

tolerance-level residues and 100 percent 

crop treated (PCT) for all existing uses 

of diquat dibromide and the proposed 

new use on canola. 

ii. Chronic exposure. In conducting 

the chronic dietary exposure assessment 

EPA used the food consumption data 

from the USDA 1994–1996 and 1998 

CSFII. As to residue levels in food, EPA 

assumed tolerance-level residues and 

100 PCT for crops with direct diquat 

uses. For crops with tolerances to cover 

irrigation with diquat-treated water, 

anticipated residue levels from 

irrigation trials were used in 

conjunction with estimates of percent of 

crops irrigated. For fish, average 

residues were assumed. Default 

processing factors from Dietary 

Exposure Evaluation Model v.7.81 were 

used in the analysis for all processed 

commodities, except potato chips and 

dried potato flakes, which have their 

own tolerances based on submitted 

processing data. 

iii. Cancer. Based on the results of 

carcinogenicity studies in rats and mice, 

EPA classified diquat dibromide in 

Group E (evidence of noncarcinogenicity to humans). Therefore, 

an exposure assessment to evaluate 

cancer risk is unnecessary for this 

chemical. 

iv. Anticipated residue and PCT 

information. Section 408(b)(2)(E) of 

FFDCA authorizes EPA to use available 

data and information on the anticipated 

residue levels of pesticide residues in 

food and the actual levels of pesticide 

residues that have been measured in 

food. If EPA relies on such information, 

EPA must require pursuant to section 

408(f)(1) of FFDCA that data be 

provided 5 years after the tolerance is 

established, modified, or left in effect, 

demonstrating that the levels in food are 

not above the levels anticipated. For the 

present action, EPA will issue such Data 

Call-Ins as are required by section 

408(b)(2)(E) of FFDCA and authorized 

under section 408(f)(1) of FFDCA. Data 

will be required to be submitted no later 

than 5 years from the date of issuance 

of these tolerances. 

Section 408(b)(2)(F) of FFDCA states 

that the Agency may use data on the 

actual percent of food treated for 

assessing chronic dietary risk only if: 

• Condition a: The data used are 

reliable and provide a valid basis to 

show what percentage of the food 

derived from such crop is likely to 

contain the pesticide residue. 

• Condition b: The exposure estimate 

does not underestimate exposure for any 

significant subpopulation group. 

• Condition c: Data are available on 

pesticide use and food consumption in 

a particular area, the exposure estimate 

does not understate exposure for the 

population in such area. 

In addition, the Agency must provide 

for periodic evaluation of any estimates 

used. To provide for the periodic 

evaluation of the estimate of PCT as 

required by section 408(b)(2)(F) of 

FFDCA, EPA may require registrants to 

submit data on PCT. 

The Agency estimated the PCT for 

existing uses as follows: 

EPA estimated PCT for several 

commodities that have tolerances to 

cover inadvertent residues of diquat 

from irrigation with diquat dibromidetreated water: Barley 36%; corn 19%; 

legume vegetables (subgroup 6C) 32%; 

oats 7%; sorghum 15%; soybean 9%; 

sugarcane 54%; and wheat 14%. One 

hundred PCT was assumed for all other 

irrigated crops and crops with direct 

diquat dibromide uses. 

EPA estimated PCT for these 

commodities by estimating the percent 

crop irrigated, which serves as an 

upperbound for crops that may be 

exposed to diquat in irrigation water. 

The percent crop irrigated is an estimate 

of the share of total production that is 

irrigated, and is based on 2009 data 

from USDA’s National Agricultural 

Statistics Service. Use of these estimates 

in the exposure assessment is 

conservative, because it is the 

equivalent of assuming 100% of 

irrigated crops are irrigated with water 

from diquat-treated canals. In fact, even 

in areas with surface water delivery 

systems, all irrigation canals may not be 

treated with diquat. Additionally, some 

crops, even in the heavily irrigated areas 

of the West, are not irrigated, such as 

dryland grain production. 

The Agency believes that the three 

conditions discussed in Unit III.C.1.iv. 

have been met. With respect to 

Condition a, PCT estimates are derived 

from Federal market survey data, which 

are reliable and have a valid basis. The 

Agency is reasonably certain that the 

percentage of the food treated is not 

likely to be an underestimation. As to 

Conditions b and c, regional 

consumption information and 

consumption information for significant 

subpopulations is taken into account 

through EPA’s computer-based model 

for evaluating the exposure of 

significant subpopulations including 

several regional groups. Use of this 

consumption information in EPA’s risk 

assessment process ensures that EPA’s 

exposure estimate does not understate 

exposure for any significant 

subpopulation group and allows the 

Agency to be reasonably certain that no 

regional population is exposed to 

residue levels higher than those 

estimated by the Agency. Other than the 

data available through national food 

consumption surveys, EPA does not 

have available reliable information on 

the regional consumption of food to 

which diquat dibromide may be applied 

in a particular area. 

2. Dietary exposure from drinking 

water. Diquat dibromide is registered for 

both terrestrial and aquatic uses. The 

Agency used screening level water 

exposure models to estimate residues of 

diquat in drinking water from the 

terrestrial uses. These simulation 


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models take into account data on the 

physical, chemical, and fate/transport 

characteristics of diquat dibromide. 

Further information regarding EPA 

drinking water models used in pesticide 

exposure assessment can be found at 

http://www.epa.gov/oppefed1/models/ 

water/index.htm. 

Based on the First Index Reservoir 

Screening Tool (FIRST) and Screening 

Concentration in Ground Water (SCIGROW) models, the estimated drinking 

water concentrations (EDWCs) of diquat 

dibromide from terrestrial uses for acute 

exposures are estimated to be 13.2 parts 

per billion (ppb) for surface water and 

0.006 ppb for ground water. The EDWCs 

for chronic exposures are estimated to 

be 0.4 ppb for surface water and 0.006 

ppb for ground water. 

Diquat dibromide is registered for 

aquatic weed control and, as such, may 

be applied directly to bodies of water. 

The maximum contaminant level (MCL) 

for diquat established by the EPA Office 

of Water is 20 ppb. EPA does not expect 

residues from direct applications of 

diquat dibromide to water to exceed the 

MCL because of the tendency of diquat 

to sorb nearly irreversably to soil and 

sediment. 

Since direct aquatic applications are 

estimated to result in higher 

concentrations of diquat in drinking 

water than terrestrial uses, EPA used the 

MCL of 20 ppb to assess the 

contribution to drinking water in both 

the acute and chronic dietary risk 

assessments. 

3. From non-dietary exposure. The 

term ‘‘residential exposure’’ is used in 

this document to refer to nonoccupational, non-dietary exposure 

(e.g., for lawn and garden pest control, 

indoor pest control, termiticides, and 

flea and tick control on pets). 

Diquat dibromide is currently 

registered for the following uses that 

could result in residential exposures: 

Applications to turf, recreational ponds 

and lakes; general weed control in and 

around home and garden sites; and 

landscape uses by residential handlers. 

EPA assessed residential exposure using 

the following assumptions: Residential 

handlers may receive short-term dermal 

and inhalation exposure when applying 

diquat dibromide products. EPA 

assessed short-term dermal and 

inhalation residential handler exposures 

for four scenarios: Mixing, loading, and 

applying products with a low-pressure 

handwand or backpack sprayer; and 

applying diquat dibromide products in 

an aerosol can or using a trigger pump 

sprayer. Adults and children may also 

be exposed to diquat dibromide residues 

on a short-term basis through dermal 

contact with treated turf and from 

swimming activities in treated 

recreational ponds and lakes. In 

addition, toddlers may receive shortterm oral exposure from incidental 

ingestion during post-application 

activities on treated turf. EPA assessed 

the following post-application exposure 

scenarios: 

i. Adult and toddler post-application 

dermal exposure, 

ii. Recreational exposure from playing 

golf on treated turf, 

iii. Toddlers’ incidental ingestion of 

pesticide residues on lawns from handto-mouth transfer, 

iv. Toddlers’ object-to-mouth transfer 

from mouthing of pesticide-treated 

turfgrass, 

v. Toddlers’ incidental ingestion of 

soil from pesticide-treated residential 

areas, and 

vi. Recreational exposure of adults 

and children from swimming in treated 

ponds and lakes. 

Further information regarding EPA 

standard assumptions and generic 

inputs for residential exposures may be 

found at http://www.epa.gov/pesticides/ 

trac/science/trac6a05.pdf. 

4. Cumulative effects from substances 

with a common mechanism of toxicity. 

Section 408(b)(2)(D)(v) of FFDCA 

requires that, when considering whether 

to establish, modify, or revoke a 

tolerance, the Agency consider 

‘‘available information’’ concerning the 

cumulative effects of a particular 

pesticide’s residues and ‘‘other 

substances that have a common 

mechanism of toxicity.’’ 

EPA has not found diquat dibromide 

to share a common mechanism of 

toxicity with any other substances, and 

diquat dibromide does not appear to 

produce a toxic metabolite produced by 

other substances. For the purposes of 

this tolerance action, therefore, EPA has 

assumed that diquat dibromide does not 

have a common mechanism of toxicity 

with other substances. For information 

regarding EPA’s efforts to determine 

which chemicals have a common 

mechanism of toxicity and to evaluate 

the cumulative effects of such 

chemicals, see EPA’s website at http:// 

www.epa.gov/pesticides/cumulative. 

D. Safety Factor for Infants and 

Children 

1. In general. Section 408(b)(2)(C) of 

FFDCA provides that EPA shall apply 

an additional tenfold (10X) margin of 

safety for infants and children in the 

case of threshold effects to account for 

prenatal and postnatal toxicity and the 

completeness of the database on toxicity 

and exposure unless EPA determines 

based on reliable data that a different 

margin of safety will be safe for infants 

and children. This additional margin of 

safety is commonly referred to as the 

Food Quality Protection Act (FQPA) 

Safety Factor (SF). In applying this 

provision, EPA either retains the default 

value of 10X, or uses a different 

additional safety factor when reliable 

data available to EPA support the choice 

of a different factor. 

2. Prenatal and postnatal sensitivity. 

The prenatal and postnatal toxicity 

database for diquat dibromide includes 

developmental toxicity studies in rats, 

mice, and rabbits and a 2–generation 

reproduction toxicity study in rats. 

There was no evidence of increased 

quantitative or qualitative susceptibility 

of fetuses or offspring in any of these 

studies. 

In the developmental study in rats, 

fetal effects (decreased fetal, litter, and 

gravid uterine weights; an increased 

incidence of fetuses with hemorrhagic 

kidney; and delayed skeletal 

ossification) occurred at a higher dose 

than the dose causing effects in 

maternal animals (decreased bodyweight gains and food consumption 

during dosing). At the LOAEL for fetal 

effects, maternal effects included one 

death and clinical signs (piloerection 

and subdued activity). In the 

developmental study in rabbits, fetal 

effects (decreased fetal body weight, an 

increased incidence of friable/mottled 

livers, and an increased incidence of 

minor skeletal alterations) also occurred 

at a higher dose than the dose causing 

maternal toxicity (body-weight loss and 

decreased food consumption). At the 

LOAEL for fetal effects, maternal effects 

included deaths and clinical signs 

(diarrhea, subdued activity, thin 

appearance, mucus, blood, little or no 

feces in tray). Results in the mouse 

developmental toxicity study were 

similar. Fetal effects (decreased fetal 

body weight and an increased incidence 

of overall skeletal alterations) occurred 

at a higher dose than the dose causing 

maternal toxicity (mortality, clinical 

signs (piloerection, respiratory sounds), 

and decreased body weight gain during 

the dosing period). Maternal effects at 

the LOAEL for fetal effects included 

additional clinical signs (abnormal 

posture, lethargy, tremors, unsteadiness 

on feet, emaciation, ptosis) and a slight 

decrease in body weight (91% of 

control) at termination. 

In the 2–generation reproduction 

study in rats, offspring effects included 

a decreased number of live pups per 

litter on days 1–22, decreased pup body 

weight gain during lactation, and an 

increased incidence of kidney lesions. 

Parental effects, including clinical signs, 

ulceration of the tongue, and partial/ 


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Federal Register / Vol. 75, No. 101 / Wednesday, May 26, 2010 / Rules and Regulations 29439 

total cataract, were observed at the same 

dose causing toxicity in the offspring. 

3. Conclusion. EPA has determined 

that reliable data show the safety of 

infants and children would be 

adequately protected if the FQPA SF 

were reduced to 1X. That decision is 

based on the following findings: 

i. The toxicity database for diquat 

dibromide is adequate to assess its 

prenatal and postnatal toxicity. In 

accordance with Part 158 Toxicology 

Data requirements, an immunotoxicity 

study (Harmonized Test Guideline 

870.7800) is required for diquat 

dibromide. In the absence of specific 

immunotoxicity studies, EPA has 

evaluated the available toxicity data for 

evidence of immunotoxicity. There are 

no indications in the available studies 

that organs associated with immune 

function, such as the thymus and 

spleen, are affected by diquat 

dibromide. Therefore, EPA does not 

believe that conducting immunotoxicity 

testing will result in a point of departure 

lower than those already selected for 

diquat dibromide, and an additional 

database uncertainty factor is not 

needed to account for the lack of this 

study. 

ii. There is no indication that diquat 

dibromide is a neurotoxic chemical and 

there is no need for a developmental 

neurotoxicity study or additional UFs to 

account for neurotoxicity. 

iii. There is no evidence that diquat 

dibromide results in increased 

susceptibility in in utero rats, rabbits, or 

mice in the prenatal developmental 

studies or in young rats in the 2– 

generation reproduction study. 

iv. There are no significant residual 

uncertainties identified in the exposure 

databases for diquat dibromide. 

Additional information from the canola 

residue studies on the length of storage 

of canola samples prior to analysis and 

confirmatory residue data for canola are 

required. However, as explained in this 

Unit, EPA does not expect these data to 

have a measurable impact on exposure 

estimates for diquat dibromide. 

a. Data from the West German and 

United Kingdom field trials on the 

length of storage of canola samples prior 

to analysis were not submitted. EPA is 

requiring these data; however, EPA 

already has data for other crops showing 

that diquat dibromide is stable in frozen 

storage for 6 to 8 months. In addition, 

based on its structure, EPA expects 

diquat dibromide to be stable in frozen 

storage much longer than the 6 to 8 

months for which data are available. 

Therefore, EPA does not expect the 

length of time the samples were stored 

to affect its conclusions regarding the 

field trial studies. 

b. EPA has determined that the 

residue trials conducted in European 

Union (EU) countries are adequate to 

support tolerances and conditional 

registration of diquat dibromide as a 

preharvest desiccant on canola in the 

United States. However, EPA is aware 

that the Interregional Research Project 

number 4 (IR-4) has conducted field 

trials in the U.S. that would support this 

same use pattern. Residues of diquat 

dibromide on canola grown in the U.S. 

are not expected to differ significantly 

from residues reported in the EU 

studies, since harvest aid/desiccant 

applications are made late in the 

growing season with little time between 

application and harvest. In addition, 

since the recommended tolerances for 

canola seed and meal have been 

increased by a factor of 2X to harmonize 

with Codex (See Unit IV.C below), there 

is little chance residues in the U.S. trials 

will exceed these tolerances. 

Nevertheless, since the IR-4 field work 

has already been completed and the 

study reports will be available in July, 

2011, EPA is requiring that these studies 

be submitted as a condition of 

registration to confirm the tolerance 

levels. EPA notes that canola is a minor 

contributor to estimated dietary 

exposure in both the acute and chronic 

dietary exposure assessments, 

accounting for less than 1% of total 

exposure for the most highly exposed 

population subgroup (children 1 to 2 

years old) in each case. Therefore, even 

if the U.S. field trials were to indicate 

higher residues than the EU trials, the 

impact on dietary exposure would be 

negligible. 

The acute dietary food exposure 

assessment was performed based on 100 

PCT and tolerance-level residues. The 

chronic dietary exposure assessment 

was refined using reliable irrigation data 

from USDA, average residues for fish 

from valid residue studies, and 

anticipated residues for irrigated crops 

that were derived from valid irrigation 

trials. The established MCL of 20 ppb 

used in the acute and chronic dietary 

exposure assessments is a conservative 

value that is considered protective of 

exposures from both terrestrial and 

direct aquatic applications of diquat 

dibromide. EPA used similarly 

conservative assumptions to assess 

postapplication exposure of children as 

well as incidental oral exposure of 

toddlers. These assessments will not 

underestimate the exposure and risks 

posed by diquat dibromide. 

E. Aggregate Risks and Determination of 

Safety 

EPA determines whether acute and 

chronic dietary pesticide exposures are 

safe by comparing aggregate exposure 

estimates to the acute aPAD and chronic 

cPAD. For linear cancer risks, EPA 

calculates the lifetime probability of 

acquiring cancer given the estimated 

aggregate exposure. Short-, 

intermediate-, and chronic-term risks 

are evaluated by comparing the 

estimated aggregate food, water, and 

residential exposure to the appropriate 

PODs to ensure that an adequate MOE 

exists. 

1. Acute risk. Using the exposure 

assumptions discussed in this unit for 

acute exposure, the acute dietary 

exposure from food and water to diquat 

dibromide will occupy 1% of the aPAD 

for children, 1 to 2 years old, the 

population group receiving the greatest 

exposure. 

2. Chronic risk. Using the exposure 

assumptions described in this unit for 

chronic exposure, EPA has concluded 

that chronic exposure to diquat 

dibromide from food and water will 

utilize 35% of the cPAD for children, 1 

to 2 years old, the population group 

receiving the greatest exposure. Based 

on the explanation in Unit III.C.3., 

regarding residential use patterns, 

chronic residential exposure to residues 

of diquat dibromide is not expected. 

3. Short-term risk. Short-term 

aggregate exposure takes into account 

short-term residential exposure plus 

chronic exposure to food and water 

(considered to be a background 

exposure level). Diquat dibromide is 

currently registered for uses that could 

result in short-term residential 

exposure, and the Agency has 

determined that it is appropriate to 

aggregate chronic exposure through food 

and water with short-term residential 

exposures to diquat dibromide. 

Using the exposure assumptions 

described in this unit for short-term 

exposures, EPA has concluded the 

combined short-term food, water, and 

residential exposures result in aggregate 

MOEs of 110 for infants and toddlers, 

150 for children 6 to 12 years old, and 

260 for teenagers and adults. The 

aggregate MOEs for infants and toddlers 

include dietary exposures from food and 

drinking water as well as dermal and 

incidental oral postapplication 

exposures from activities on treated turf. 

The aggregate MOE for children 

includes dietary exposures from food 

and drinking water as well as dermal 

postapplication exposure from activities 

on treated turf and exposures from 

swimming in ponds and lakes treated 

with diquat dibromide. The aggregate 

MOEs for teenagers and adult 

population subgroups include dietary 

exposures, residential handler dermal 

exposures, dermal postapplication 


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29440 Federal Register / Vol. 75, No. 101 / Wednesday, May 26, 2010 / Rules and Regulations 

exposures from activities on treated turf, 

and exposures from swimming in ponds 

and lakes treated with diquat 

dibromide. EPA did not aggregate 

residential handler inhalation exposures 

with exposures by other routes in the 

aggregate exposure assessment for 

teenagers and adults, since the effects 

associated with inhalation exposure 

(increased mean lung weight in males, 

mottling and reddening of lungs in 

females, and lung lesions) are different 

from those used to assess the dermal 

and oral routes (body-weight loss and 

decreased food consumption). 

Inhalation MOEs for residential 

handlers ranged from 570 (aerosol can 

application) to 11,000,000 (trigger 

sprayer). Because EPA’s level of concern 

for diquat dibromide is a MOE of 100 or 

below, these MOEs are not of concern. 

4. Intermediate-term risk. 

Intermediate-term aggregate exposure 

takes into account intermediate-term 

residential exposure plus chronic 

exposure to food and water (considered 

to be a background exposure level). 

EPA did not establish a POD for use 

in assessing intermediate-term 

residential exposures, because diquat 

dibromide is not registered for any use 

patterns that would result in such 

exposures. Intermediate-term risk is 

assessed based on intermediate-term 

residential exposure plus chronic 

dietary exposure. Because there is no 

intermediate-term residential exposure 

and chronic dietary exposure has 

already been assessed under the 

appropriately protective cPAD (which is 

at least as protective as the POD used to 

assess intermediate-term risk), no 

further assessment of intermediate-term 

risk is necessary, and EPA relies on the 

chronic dietary risk assessment for 

evaluating intermediate-term risk for 

diquat dibromide. 

5. Aggregate cancer risk for U.S. 

population. Based on the lack of 

evidence of carcinogenicity in two 

adequate rodent carcinogenicity studies, 

diquat dibromide is not expected to 

pose a cancer risk to humans. 

6. Determination of safety. Based on 

these risk assessments, EPA concludes 

that there is a reasonable certainty that 

no harm will result to the general 

population, or to infants and children 

from aggregate exposure to diquat 

dibromide residues. 

IV. Other Considerations 

A. Analytical Enforcement Methodology 

Adequate enforcement methodology 

(High Performance Liquid 

Chromatographic Method (HPLC)) is 

available to enforce the tolerance 

expression. The method may be 

requested from: Chief, Analytical 

Chemistry Branch, Environmental 

Science Center, 701 Mapes Rd., Ft. 

Meade, MD 20755–5350; telephone 

number: (410) 305–2905; e-mail address: 

residuemethods@epa.gov. Method A (a 

spectrophotometric method) in the 

Pesticide Analytical Manual (PAM) Vol. 

II. is also available to enforce tolerances 

for residues of diquat in/on plant and 

livestock commodities. 

B. International Residue Limits 

In making its tolerance decisions, EPA 

seeks to harmonize U.S. tolerances with 

international standards whenever 

possible, consistent with U.S. food 

safety standards and agricultural 

practices. EPA considers the 

international maximum residue limits 

(MRLs) established by the Codex 

Alimentarius Commission (Codex), as 

required by section 408(b)(4) of FFDCA. 

The Codex Alimentarius is a joint U.N. 

Food and Agriculture Organization/ 

World Health Organization food 

standards program, and it is recognized 

as an international food safety 

standards-setting organization in trade 

agreements to which the United States 

is a party. EPA may establish a tolerance 

that is different from a Codex MRL; 

however, section 408(b)(4) of FFDCA 

requires that EPA explain the reasons 

for departing from the Codex level. 

The Codex has established an MRL for 

diquat in or on rapeseed (which 

includes canola seed) at 2.0 ppm. This 

MRL is the same as the tolerance being 

established for diquat dibromide on 

canola, seed in the United States. 

C. Revisions to Petitioned-For 

Tolerances 

EPA has increased the tolerance level 

for canola, seed from 1.0 ppm to 2.0 

ppm to harmonize with the established 

Codex MRL of 2.0 ppm for rapeseed. 

EPA has also increased the tolerance 

level for canola meal from 3.0 ppm to 

6.0 ppm. The tolerance level for meal 

was derived by applying the maximum 

theoretical concentration factor of 3X for 

canola meal to the canola seed tolerance 

of 2.0 ppm. 

EPA is also correcting minor errors in 

the regulations for diquat at 40 CFR 

180.226, as follows: EPA is correcting 

typographical errors in the chemical 

name for diquat in paragraphs (a)(2)(i) 

and (a)(3). EPA is also removing 

paragraph (a)(4), which reads ‘‘There are 

no U.S. registrations as of December 6, 

1995.’’ This statement was originally 

included as a footnote to import 

tolerances for banana and coffee, 

established in the Federal Register of 

March 27, 1996 (61 FR 13474) (FRL– 

5348–1). The statement was 

inadvertently moved to a separate 

paragraph in subsequent editions of the 

CFR. EPA is correcting this error by 

removing paragraph (a)(4) and adding 

an updated statement regarding U.S. 

registrations as a footnote to the banana 

and coffee tolerances. The updated 

footnote to the table in paragraph (a)(3) 

reads ‘‘There are no U.S. registrations as 

of May 26, 2010.’’ 

V. Conclusion 

Therefore, tolerances are established 

for residues of diquat, 6,7- 

dihydrodipyrido(1,2-a:2’1’- 

c)pyrazinediium derived from 

application of the dibromide salt and 

calculated as the cation, in or on canola, 

meal at 6.0 ppm; and canola, seed at 2.0 

ppm. 

VI. Statutory and Executive Order 

Reviews 

This final rule establishes tolerances 

under section 408(d) of FFDCA in 

response to a petition submitted to the 

Agency. The Office of Management and 

Budget (OMB) has exempted these types 

of actions from review under Executive 

Order 12866, entitled Regulatory 

Planning and Review (58 FR 51735, 

October 4, 1993). Because this final rule 

has been exempted from review under 

Executive Order 12866, this final rule is 

not subject to Executive Order 13211, 

entitled Actions Concerning Regulations 

That Significantly Affect Energy Supply, 

Distribution, or Use (66 FR 28355, May 

22, 2001) or Executive Order 13045, 

entitled Protection of Children from 

Environmental Health Risks and Safety 

Risks (62 FR 19885, April 23, 1997). 

This final rule does not contain any 

information collections subject to OMB 

approval under the Paperwork 

Reduction Act (PRA), 44 U.S.C. 3501 et 

seq., nor does it require any special 

considerations under Executive Order 

12898, entitled Federal Actions to 

Address Environmental Justice in 

Minority Populations and Low-Income 

Populations (59 FR 7629, February 16, 

1994). 

Since tolerances and exemptions that 

are established on the basis of a petition 

under section 408(d) of FFDCA, such as 

the tolerance in this final rule, do not 

require the issuance of a proposed rule, 

the requirements of the Regulatory 

Flexibility Act (RFA) (5 U.S.C. 601 et 

seq.) do not apply. 

This final rule directly regulates 

growers, food processors, food handlers, 

and food retailers, not States or tribes, 

nor does this action alter the 

relationships or distribution of power 

and responsibilities established by 

Congress in the preemption provisions 

of section 408(n)(4) of FFDCA. As such, 


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Federal Register / Vol. 75, No. 101 / Wednesday, May 26, 2010 / Rules and Regulations 29441 

the Agency has determined that this 

action will not have a substantial direct 

effect on States or tribal governments, 

on the relationship between the national 

government and the States or tribal 

governments, or on the distribution of 

power and responsibilities among the 

various levels of government or between 

the Federal Government and Indian 

tribes. Thus, the Agency has determined 

that Executive Order 13132, entitled 

Federalism (64 FR 43255, August 10, 

1999) and Executive Order 13175, 

entitled Consultation and Coordination 

with Indian Tribal Governments (65 FR 

67249, November 9, 2000) do not apply 

to this final rule. In addition, this final 

rule does not impose any enforceable 

duty or contain any unfunded mandate 

as described under Title II of the 

Unfunded Mandates Reform Act of 1995 

(UMRA) (Public Law 104–4). 

This action does not involve any 

technical standards that would require 

Agency consideration of voluntary 

consensus standards pursuant to section 

12(d) of the National Technology 

Transfer and Advancement Act of 1995 

(NTTAA), Public Law 104–113, section 

12(d) (15 U.S.C. 272 note). 

VII. Congressional Review Act 

The Congressional Review Act, 5 

U.S.C. 801 et seq., generally provides 

that before a rule may take effect, the 

agency promulgating the rule must 

submit a rule report to each House of 

the Congress and to the Comptroller 

General of the United States. EPA will 

submit a report containing this rule and 

other required information to the U.S. 

Senate, the U.S. House of 

Representatives, and the Comptroller 

General of the United States prior to 

publication of this final rule in the 

Federal Register. This final rule is not 

a ‘‘major rule’’ as defined by 5 U.S.C. 

804(2). 

List of Subjects in 40 CFR Part 180 

Environmental protection, 

Administrative practice and procedure, 

Agricultural commodities, Pesticides 

and pests, Reporting and recordkeeping 

requirements. 

Dated: May 18, 2010. 

Daniel J. Rosenblatt, 

Acting Director, Registration Division, Office 

of Pesticide Programs. 

■ Therefore, 40 CFR chapter I is 

amended as follows: 

PART 180—[AMENDED] 

■ 1. The authority citation for part 180 

continues to read as follows: 

Authority: 21 U.S.C. 321(q), 346a and 371. 

■ 2. Section 180.226 is amended as 

follows: 

i. Alphabetically add commodities to 

the table in paragraph (a)(1); 

ii. Revise introductory text in 

paragraph (a)(2)(i); 

iii. Revise paragraph (a)(3); 

iv. Remove paragraph (a)(4); and 

v. Redesignate paragraph (a)(5) as 

(a)(4). 

The amendments read as follows: 

§ 180.226 Diquat; tolerances for residues. 

(a) * * * (1) * * * 

Commodity Parts per million 

* * * * * 

Canola, meal .................. 6.0 

Canola, seed .................. 2.0 

* * * * * 

(2)(i) Tolerances are established for 

residues of the herbicide diquat (6,7 

dihydrodipyrido(1,2-a:2’1’- 

c)pyrazinediium) (calculated as the 

cation) derived from the application of 

the dibromide salt to ponds, lakes, 

reservoirs, marshes, drainage ditches, 

canals, streams, and rivers which are 

slow-moving or quiescent in programs 

of the Corp of Engineers or other Federal 

or State public agencies and to ponds, 

lakes and drainage ditches only where 

there is little or no outflow of water and 

which are totally under the control of 

the user, in or on the following food 

commodities: 

* * * * * 

(3) Tolerances are established for the 

plant growth regulator diquat (6,7 

dihydrodipyrido(1,2-a:2’1’- 

c)pyrazinediium) derived from 

application of the dibromide salt and 

calculated as the cation in or on the 

following food commodites: 

Commodity Parts per million 

Banana1 .......................... 0.05 

Coffee, bean, green1 ...... 0.05 

Soybean, hulls ................ 0.6 

1There are no U.S. registrations as of May 

26, 2010. 

* * * * * 

[FR Doc. 2010–12648 Filed 5–25–10; 8:45 am] 

BILLING CODE 6560–50–S 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 180 

[EPA–HQ–OPP–2009–0273; FRL–8825–3] 

Novaluron; Pesticide Tolerances 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Final rule. 

SUMMARY: This regulation establishes 

tolerances for residues of novaluron in 

or on multiple commodities which are 

identified and discussed later in this 

document. This regulation additionally 

revises several established tolerances for 

residues of novaluron. MakhteshimAgan of North America, Inc., requested 

these tolerances under the Federal Food, 

Drug, and Cosmetic Act (FFDCA). 

DATES: This regulation is effective May 

26, 2010. Objections and requests for 

hearings must be received on or before 

July 26, 2010, and must be filed in 

accordance with the instructions 

provided in 40 CFR part 178 (see also 

Unit I.C. of the SUPPLEMENTARY

INFORMATION). 

ADDRESSES: EPA has established a 

docket for this action under docket 

identification (ID) number EPA–HQ– 

OPP–2009–0273. All documents in the 

docket are listed in the docket index 

available at http://www.regulations.gov. 

Although listed in the index, some 

information is not publicly available, 

e.g., Confidential Business Information 

(CBI) or other information whose 

disclosure is restricted by statute. 

Certain other material, such as 

copyrighted material, is not placed on 

the Internet and will be publicly 

available only in hard copy form. 

Publicly available docket materials are 

available in the electronic docket at 

http://www.regulations.gov, or, if only 

available in hard copy, at the OPP 

Regulatory Public Docket in Rm. S– 

4400, One Potomac Yard (South Bldg.), 

2777 S. Crystal Dr., Arlington, VA. The 

Docket Facility is open from 8:30 a.m. 

to 4 p.m., Monday through Friday, 

excluding legal holidays. The Docket 

Facility telephone number is (703) 305– 

5805. 

FOR FURTHER INFORMATION CONTACT: 

Laura Nollen, Registration Division 

(7505P), Office of Pesticide Programs, 

Environmental Protection Agency, 1200 

Pennsylvania Ave., NW., Washington, 

DC 20460–0001; telephone number: 

(703) 305–7390; e-mail address: 

nollen.laura@epa.gov. 

SUPPLEMENTARY INFORMATION: 

I. General Information 

A. Does this Action Apply to Me? 

You may be potentially affected by 

this action if you are an agricultural 

producer, food manufacturer, or 

pesticide manufacturer. Potentially 

affected entities may include, but are 

not limited to those engaged in the 

following activities: 

• Crop production (NAICS code 111). 


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