Federal Register / Vol. 75, No. 171 / Friday, September 3, 2010 / Rules and Regulations 54033 

the Comptroller General of the United 

States prior to publication of the rule in 

the Federal Register. A major rule 

cannot take effect until 60 days after it 

is published in the Federal Register. 

This action is not a ‘‘major rule’’ as 

defined by 5 U.S.C. 804(2). 

Under section 307(b)(1) of the CAA, 

petitions for judicial review of this 

action must be filed in the United States 

Court of Appeals for the appropriate 

circuit by November 2, 2010. Filing a 

petition for reconsideration by the 

Administrator of this final rule does not 

affect the finality of this action for the 

purposes of judicial review nor does it 

extend the time within which a petition 

for judicial review may be filed, and 

shall not postpone the effectiveness of 

such rule or action. This action may not 

be challenged later in proceedings to 

enforce its requirements (see section 

307(b)(2)). 

List of Subjects 

40 CFR Part 52 

Environmental protection, Air 

pollution control, Incorporation by 

reference, Particulate matter, Reporting 

and recordkeeping requirements. 

40 CFR Part 81 

Environmental protection, Air 

pollution control, National parks, 

Wilderness areas. 

Dated: July 29, 2010. 

Jeff Scott, 

Acting Regional Administrator, Region 9. 

■ Chapter I, title 40 of the Code of 

Federal Regulations is amended as 

follows: 

PART 52—[AMENDED] 

■ 1. The authority citation for Part 52 

continues to read as follows: 

Authority: 42 U.S.C. 7401 et seq. 

Subpart F—California 

■ 2. Section 52.220 is amended by 

adding paragraph (c)(380) to read as 

follows: 

§ 52.220 Identification of plan. 

* * * * * 

(c) * * * 

(380) The following plan was 

submitted on July 14, 2010, by the 

Governor’s Designee. 

(i) Incorporation by reference. 

(A) Great Basin Unified Air Pollution 

Control District. 

(1) ‘‘Board Order #080128–01 

Requiring the City of Los Angeles to 

Undertake Measures to Control PM–10 

Emissions from the Dried Bed of Owens 

Lake,’’ including Attachments A–D, 

adopted February 1, 2008, and included 

as Appendix C to the ‘‘2010 PM–10 

Maintenance Plan and Redesignation 

Request for the Coso Junction Planning 

Area,’’ adopted May 17, 2010. 

(ii) Additional materials. 

(A) Great Basin Unified Air Pollution 

Control District (GBUAPCD). 

(1) Non-regulatory portions of ‘‘The 

2010 PM–10 Maintenance Plan and 

Redesignation Request for the Coso 

Junction Planning Area’’ (the 2010 Plan), 

including Appendices A, B, and D, 

adopted May 17, 2010. 

(2) Letter dated June 10, 2010 from 

Theodore D. Schade, GBUAPCD, to 

Deborah Jordan, United States 

Environmental Protection Agency 

Region 9, regarding Coso Junction PM– 

10 Contingency Measures. 

(3) GBUAPCD Board Resolution 

2010–01, dated May 17, 2010, adopting 

the 2010 Plan. 

(B) California Air Resources Board 

(CARB). 

(1) CARB Resolution 10–25, dated 

June 24, 2010, adopting the 2010 Plan. 

PART 81—[AMENDED] 

■ 3. The authority citation for part 81 

continues to read as follows: 

Authority: 42 U.S.C. 7401 et seq. 

Subpart C—[Amended] 

■ 4. Section 81.305 is amended in the 

table for ‘‘California–PM–10’’ by revising 

the entry under Inyo County for the 

‘‘Coso Junction planning area’’ to read as 

follows: 

§ 81.305 California. 

* * * * * 

CALIFORNIA—PM–10 

Designated area 

Designation Classification 

Date Type Date Type 

Inyo County 

Coso Junction planning area .......................... October 4, 2010 ......... Attainment.

That portion of Inyo County contained within 

Hydrologic Unit #18090205.

* * * * * * * 

* * * * * 

[FR Doc. 2010–21960 Filed 9–2–10; 8:45 am] 

BILLING CODE 6560–50–P 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 180 

[EPA–HQ–OPP–2009–0910; FRL–8842–7] 

Thiabendazole; Pesticide Tolerances 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Final rule. 

SUMMARY: This regulation establishes 

tolerances for residues of thiabendazole, 

and its metabolites, benzimidazole (free 

and conjugated), [2-(4-thiazolyl) 

benzimidazole], in or on corn. Syngenta 

Crop Protection requested these 

tolerances under the Federal Food, 

Drug, and Cosmetic Act (FFDCA). 

DATES: This regulation is effective 

September 3, 2010. Objections and 

requests for hearings must be received 

on or before November 2, 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–2009–0910. 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 


erowe on DSK5CLS3C1PROD with RULES
54034 Federal Register / Vol. 75, No. 171 / Friday, September 3, 2010 / Rules and Regulations 

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: 

Janet Whitehurst, Office of Pesticide 

Programs, Environmental Protection 

Agency, 1200 Pennsylvania Ave., NW., 

Washington, DC 20460–0001; telephone 

number: (703) 305–6129; e-mail address: 

whitehurst.janet@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. 

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–2009–0910 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 

before November 2, 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–2009–0910, 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 June 6, 2010 

(75 FR 35804) (FRL–8831–3), 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 0F7730) by 

Syngenta Crop Science. The petition 

requested that 40 CFR 180.242 be 

amended by establishing tolerances for 

residues of the fungicide thiabendazole, 

and its metabolites, benzimidazole (free 

and conjugated), [2-(4-thiazolyl) 

benzimidazole], in or on corn grain and 

other corn commodities at 0.01 parts per 

million (ppm). That notice referenced a 

summary of the petition prepared by 

Syngenta Crop Protection, the registrant, 

which is available in the docket, http:// 

www.regulations.gov. There were no 

comments received in response to the 

notice of filing. 

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 thiabendazole 

including exposure resulting from the 

tolerances established by this action. 

EPA’s assessment of exposures and risks 

associated with thiabendazole 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. 

The target organs for thiabendazole 

toxicity are the liver and thyroid. Effects 

to these organs were observed in 

multiple studies and across species. 

Thiabendazole causes thyroid tumors in 

male rats through an established nonlinear mode of action involving 

perturbation of thyroid hormone 

synthesis. Accordingly, thiabendazole is 

classified as ‘‘not likely to be 

carcinogenic to humans at doses that do 

not alter rat thyroid hormone 

homeostasis.’’ There is no evidence of 

neurotoxicity in the existing database, 


erowe on DSK5CLS3C1PROD with RULES
Federal Register / Vol. 75, No. 171 / Friday, September 3, 2010 / Rules and Regulations 54035 

and in developmental and reproductive 

studies, effects to offspring are observed 

only at doses toxic to the parents. There 

are no effects seen in the toxicity 

database that would be attributable to a 

single exposure of thiabendazole. The 

Agency is regulating chronic dietary risk 

with a chronic RfD at a dose below 

which thyroid hormone balance is not 

impacted and consequently is protective 

of potential carcinogenic effects. 

Specific information on the studies 

received and the nature of the adverse 

effects caused by thiabendazole as well 

as the no-observed-adverse-effect-level 

(NOAEL) and the lowest-observedadverse-effect-level (LOAEL) from the 

toxicity studies can be found at http:// 

www.regulations.gov in the document 

entitled ‘‘Thiabendazole Human Health 

Risk Assessment for Seed Treatment 

Use on Corn,’’ pages 6–11 in docket ID 

number EPA–HQ–OPP–2007–0546. 

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 

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 thiabendazole used for 

human risk assessment is shown in the 

following Table 1. 

TABLE 1.—SUMMARY OF TOXICOLOGICAL DOSES AND ENDPOINTS FOR THIAZBENDAZOLE FOR USE IN HUMAN HEALTH

RISK ASSESSMENT

Exposure/Scenario Point of Departure Uncertainty/FQPA Factors Level of Concern for Risk 

Assessment 

Study and Toxicological 

Effects 

Acute dietary (general 

population including females 13–49 years) 

No effect attributable to a single dose seen in the database 

Chronic dietary NOAEL = 10 mg/kg/day UFA = 3x 

UFH = 10x 

FQPA = UFDB = 10x 

cRfD = 0.033 mg/kg/day 

cPAD = 0.033 mg/kg/day 

2-Year Feed/Chronic Carcinogenicity in the Rat 

LOAEL = 30 mg/kg/day 

based on decreased 

body weight gains and 

histopathological 

changes in liver and 

thyroid 

Incidental oral (ST/IT) NOAEL = 10 mg/kg/day UFA = 3x 

UFH = 10x 

FQPA = UFDB = 10x 

LOC for MOE = 300 Subchronic oral toxicity 

study - rat 

LOAEL = 40 mg/kg/day 

based on reduced body 

weight gains and 

histopathological 

changes in the bone 

marrow, liver and thyroid 

Dermal short-term (1-30 

days) DAF = 0.5% 

NOAEL= 10 mg/kg/day UFA = 3x 

UFH = 10 

FQPA = UFDB = 10x 

Occupational and residential LOC for MOE = 300 Subchronic oral toxicity 

study - rat 

LOAEL = 40 mg/kg/day 

based on reduced body 

weight gains and 

histopathological 

changes in the bone 

marrow, liver and thyroid 

Inhalation short-term (1–30 

days) 

NOAEL = 10 mg/kg/day UFA = 3x 

UFH =10x 

FQPA = UFDB = 10x 

Occupational LOC for 

MOE = 300 

Subchronic oral toxicity 

study - rat 

LOAEL = 40 mg/kg/day 

based on reduced body 

weight gains and 

histopathological 

changes in the bone 

marrow, liver and thyroid 


erowe on DSK5CLS3C1PROD with RULES
54036 Federal Register / Vol. 75, No. 171 / Friday, September 3, 2010 / Rules and Regulations 

TABLE 1.—SUMMARY OF TOXICOLOGICAL DOSES AND ENDPOINTS FOR THIAZBENDAZOLE FOR USE IN HUMAN HEALTH

RISK ASSESSMENT—Continued 

Exposure/Scenario Point of Departure Uncertainty/FQPA Factors Level of Concern for Risk 

Assessment 

Study and Toxicological 

Effects 

Dermal intermediate-term 

(1-6 mos) DAF = 0.5%* 

NOAEL = 10 mg/kg/day UFA = 3x 

UFH = 10x 

FQPA = UFDB = 10x 

Occupational LOC for 

MOE = 300 

Subchronic oral toxicity 

study - rat 

LOAEL = 40 mg/kg/day 

based on reduced body 

weight gains and 

histopathological 

changes in the bone 

marrow, liver and thyroid 

Inhalation intermediateterm (1-6 mos) NOAEL = 10 mg/kg/day UFA = 3x 

UFH = 10x 

FQPA = UFDB = 10x 

Occupational LOC for 

MOE = 300 

Subchronic oral toxicity 

study - rat 

LOAEL = 40 mg/kg/day 

based on reduced body 

weight gains and 

histopathological 

changes in the bone 

marrow, liver and thyroid 

Cancer (all routes) Not likely to be carcinogenic to humans at doses that do not alter rat thyroid hormone homeostasis 

UFA = extrapolation from animal to human (interspecies). 

UFH = potential variation in sensitivity among members of the human population (intraspecies). 

UFDB = to account for the absence of data or other data deficiency. 

FQPA SF = Food Quality Protection Act Safety Factor. 

PAD = population adjusted dose (a = acute, c = chronic). 

RfD = reference dose. MOE = margin of exposure. 

LOC = level of concern. 

The overall composite uncertainty 

factor for assessing thiabendazole risk is 

300X. That is based on a 10X for 

intraspecies variability among humans, 

3X for interspecies pharmacokinetic 

differences between humans and rats, 

and 10X for FQPA safety factor for 

database uncertainty. The 3X 

interspecies factor was chosen because 

the endpoint used for the Point of 

Departure is a thyroid effect and adult 

rats are known to be more sensitive 

pharmacodynamically to thyroid 

toxicants than humans. Focusing on the 

thyroid effects will produce the most 

protective PAD despite the fact that a 

reduced interspecies factor is 

appropriate as to this effect. 

C. Exposure Assessment 

1. Dietary exposure from food and 

feed uses. In evaluating dietary 

exposure to thiabendazole, EPA 

considered exposure under the 

petitioned-for tolerances as well as all 

existing thiabendazole tolerances in 40 

CFR 180.242. EPA assessed dietary 

exposures from thiabendazole 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. No such effects were 

identified in the toxicological studies 

for thiabendazole; therefore, a 

quantitative acute dietary exposure 

assessment is unnecessary. 

ii. Chronic exposure. Thiabendazole 

chronic dietary exposure assessments 

were conducted using the DEEMFCIDTM (ver. 2.03) which incorporates 

consumption data from the United 

States Department of Agriculture 

(USDA) Continuing Survey of Food 

Intake by Individuals (CSFII) (1994– 

1996 and 1998). In estimating residue 

levels on food, EPA assumed residues in 

corn were at tolerances levels. For other 

commodities, EPA estimated residue 

levels based on residue monitoring data. 

EPA also used percent crop treated 

(PCT) data on some commodities. 

iii. 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 FFDCA 

section 408(f)(1) 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 FFDCA section 

408(b)(2)(E) and authorized under 

FFDCA section 408(f)(1). 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 FFDCA section 408(b)(2)(F), 

EPA may require registrants to submit 

data on PCT. 

The following PCT were used in the 

assessment: 

• Apple 30%. 

• Orange 20%. 

• Pear 45%. 

• Potato 1%. 

• Soybeans 1%. 

• Strawberry 6.3% imported. 

• Sweet potato 1%. 

• Wheat 1%. 

In most cases, EPA uses available data 

from USDA/National Agricultural 


erowe on DSK5CLS3C1PROD with RULES
Federal Register / Vol. 75, No. 171 / Friday, September 3, 2010 / Rules and Regulations 54037 

Statistics Service (NASS), proprietary 

market surveys, and the National 

Pesticide Use Database for the chemical/ 

crop combination for the most recent 6– 

7 years. EPA uses an average PCT for 

chronic dietary risk analysis. The 

average PCT figure for each existing use 

is derived by combining available 

public and private market survey data 

for that use, averaging across all 

observations, and rounding to the 

nearest 5%, except for those situations 

in which the average PCT is less than 

one. In those cases, 1% is used as the 

average PCT and 2.5% is used as the 

maximum PCT. EPA uses a maximum 

PCT for acute dietary risk analysis. The 

maximum PCT figure is the highest 

observed maximum value reported 

within the recent 6 years of available 

public and private market survey data 

for the existing use and rounded up to 

the nearest multiple of 5%. 

The Agency believes that the three 

conditions discussed above have been 

met. With respect to Condition a, PCT 

estimates are derived from Federal and 

private 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 thiabendazole may be applied in 

a particular area. 

iv. Cancer. EPA has concluded that 

thiabendazole does not pose a cancer 

risk to humans. Therefore, a dietary 

exposure assessment for the purpose of 

assessing cancer risk is unnecessary. 

2. Dietary exposure from drinking 

water. The Agency used screening level 

water exposure models in the dietary 

exposure analysis and risk assessment 

for thiabendazole drinking water. These 

simulation models take into account 

data on the physical, chemical, and fate/ 

transport characteristics of 

thiabendazole. 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. 

A Tier 2 drinking water assessment 

was conducted for thiabendazole in 

surface water and Tier 1 in ground 

water for the proposed new seed 

treatment product on corn. The annual 

mean concentration of 0.0000048 ppm 

was used in the chronic dietary 

exposure analysis. Drinking water 

concentrations from ground water 

sources were estimated, but were lower 

than that estimated concentration from 

surface water, so the estimated 

concentration from surface water 

sources was used in the dietary 

exposure analysis. 

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). 

Thiabendazole is currently registered 

for the following uses that could result 

in residential exposures: paint and 

sponges. These residential uses have 

been assessed and aggregated with the 

food and water exposures. EPA assumed 

that 5% of the thiabendazole on sponges 

is transferred to the surface being wiped 

(such as counters, tables, floors) each 

day. 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 thiabendazole to 

share a common mechanism of toxicity 

with any other substances, and 

thiabendazole does not appear to 

produce a toxic metabolite produced by 

other substances. For the purposes of 

this tolerance action, therefore, EPA has 

assumed that thiabendazole 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 

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. 

In prenatal developmental toxicity 

studies in rats, rabbits, and mice and in 

the 2-generation reproduction study in 

rats, effects in the fetuses or neonates 

occurred at or above doses that caused 

maternal or parental toxicity. 

3. Conclusion. EPA is retaining a 

FQPA factor of 10X based on the 

following findings: 

i. The database for thiabendazole is 

complete except for a developmental 

thyroid study and data needed for the 

new data requirements including an 

immunotoxicity study and the 

neurotoxicity screening battery. Pending 

the outcome of the developmental 

thyroid toxicity study, there is 

uncertainty with respect to the effect of 

thiabendazole in developing offspring. 

There is evidence of thyroid toxicity 

following subchronic and chronic 

exposures to rats characterized as 

histopathological changes in the thyroid 

in multiple studies in rats. Disruption of 

thyroid homeostasis is the initial, 

critical effect that may lead to adverse 

effects on the developing nervous 

system. Thus, the absence of the 

developmental thyroid study raises 

concern whether infants and children 

are sufficiently protected from 

developmental effects. The 

developmental thyroid toxicity study 

will better address this concern than a 

developmental neurotoxicity study. The 

absence of neurotoxicity studies (acute, 

subchronic, and developmental) raise 

relatively low concern because: (1) 

Thiabendazole has shown no indication 

of neurotoxicity in relevant studies, and; 

(2) to the extent that thiabendazole’s 

thyroid effects may have neurological 

effects on the young, the nature of the 

thyroid effects (and the potential for any 

resulting neurological effects on the 

young) will be addressed by the 

developmental thyroid study. The 


erowe on DSK5CLS3C1PROD with RULES
54038 Federal Register / Vol. 75, No. 171 / Friday, September 3, 2010 / Rules and Regulations 

absence of the immunotoxicity study 

raises relatively low concern because 

there are no indications in the available 

studies that organs associated with 

immune function, such as the thymus 

and spleen, are affected by 

thiabendazole. 

ii. There is no evidence that 

thiabendazole results in increased 

susceptibility in in utero rats or rabbits 

in the prenatal developmental studies or 

in young rats in the 2-generation 

reproduction study. 

iii. There are no residual uncertainties 

identified in the exposure databases. 

The dietary food exposure assessments 

were performed based on PCT and 

anticipated residues primarily from 

Pesticide Data Program (PDP) data and 

some tolerance-level residues. These 

data are reliable and will not 

underestimate the exposure and risk. 

EPA made conservative (protective) 

assumptions in the ground water and 

surface water modeling used to assess 

exposure to thiabendazole in drinking 

water. 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 thiabendazole. 

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 population 

adjusted dose (aPAD) and chronic PAD 

(cPAD). For linear cancer risks, EPA 

calculates the lifetime probability of 

acquiring cancer given the estimated 

aggregate exposure. Short-term, 

intermediate-term, 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. An acute aggregate risk 

assessment takes into account acute 

exposure estimates from dietary 

consumption of food and drinking 

water. No adverse effect resulting from 

a single oral exposure was identified 

and no acute dietary endpoint was 

selected. Therefore, thiabendazole is not 

expected to pose an acute risk. 

2. Chronic risk. Using the exposure 

assumptions described in this unit for 

chronic exposure, EPA has concluded 

that chronic exposure to thiabendazole 

from food and water will utilize 1.4% of 

the cPAD occupied for the U.S. 

population. The most highly exposed 

subpopulation was all infants at 4.6% 

cPAD. 

3. Short- and intermediate-term risk. 

Short-term and intermediate-term 

aggregate exposure takes into account 

short-term residential exposure plus 

chronic exposure to food and water 

(considered to be a background 

exposure level). To assess short-term 

and intermediate-term aggregate risk 

likely to result from the new and 

existing thiabendazole uses, EPA 

combined average food and water 

exposures with estimates of residential 

exposure for both adult painters and 

adult females and small children 

exposed to surfaces cleaned with treated 

sponges. 

No risks of concern were seen for 

adult painters. A potential risk of 

concern would be the use of 

thiabendazole treated sponges, if the 

Agency assumes that 100% of the 

thiabendazole on a treated sponge is 

transferred to surfaces each day. It is 

very unlikely that a sponge would 

release all of the thiabendazole used to 

treat it in a single day, and the user 

would use a new sponge every day. 

Since this is a very unrealistic 

assumption, a second aggregate 

assessment was conducted assuming 

that 100% of the thiabendazole on a 

treated sponge is transferred to surfaces 

over 20 days and that each 20 days the 

user would use a new sponge. This 

assumption is still conservative because: 

(1) Sponges will generally be used much 

longer than 20 days; (2) it is very 

unlikely that 100% of the thiabendazole 

would be released from the sponge in 

such a short period given that 

environmental fate data show 

thiabendazole to have low water 

solubility indicating that thiabendazole 

will bind strongly to the sponge; and (3) 

it is very unlikely that 100% of any 

released thiabendazole would be 

transferred to countertops because this 

assumption does not account for any 

thiabendazole that is washed down the 

sink or that normally degrades. With 

this assumption, none of the aggregate 

exposures represent risks of concern, as 

all MOEs are greater than the target 

MOE of 300. 

A summary of the short-term and 

intermediate-term aggregate risk for 

thiabendazole used in the human risk 

assessment is shown in Tables 2 and 3 

of this unit. 

TABLE 2.—SHORT-TERM AND INTERMEDIATE-TERM AGGREGATE RISK FOR RESIDENTIAL PAINTER

Population Subgroup 

Average Food and 

Water Exposure (mg/kg/ 

day) 

Residential Exposure1

(mg/kg/day) 

Aggregate MOE (food 

and residential)2

U.S. Population 0.000451 0.0046 2000 

Youth (13–19 yrs) 0.000289 0.0046 2000 

Adults (20–49 yrs) 0.000308 0.0046 2000 

Adults (50 + yrs) 0.000331 0.0046 2000 

Females (13–49 yrs) 0.000333 0.0046 2000 

1 Residential Exposure = Dermal exposure + Inhalation Exposure. 

2 (Avg Food Aggregate MOE = NOAEL (10 mg/kg/day and Water Exposure + Residential Exposure). 


erowe on DSK5CLS3C1PROD with RULES
Federal Register / Vol. 75, No. 171 / Friday, September 3, 2010 / Rules and Regulations 54039 

TABLE 3.–SHORT-TERM AND INTERMEDIATE-TERM AGGREGATE RISK CALCULATIONS FOR SPONGE USAGE

Population Subgroup 

Average Food and 

Water Exposure (mg/kg/ 

day) 

Residential Exposure1

(mg/kg/day) 

Aggregate MOE (food 

and residential)2

Fraction of Thiabendazole Transferred Daily From Sponge to Surface = 100% 

Children (3–5 yrs) 0.001252 0.08 120 

Females (13–49 yrs) 0.000333 0.02 500 

Fraction of Thiabendazole Transferred From Sponge to Surface = 5% 

Children (3–5 yrs) 0.001252 0.004 2300 

Females (13–49 yrs) 0.000333 0.001 4500 

1 Residential Exposure = Dermal exposure + Inhalation Exposure. 

2Aggregate MOE = NOAEL (10 mg/kg/day) ÷ (Average Food & Water Exposure plus Residential Exposure). 

5. Aggregate cancer risk for U.S. 

population. Based on the lack of 

evidence of carcinogenicity in two 

adequate rodent carcinogenicity studies, 

thiabendazole 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 

thiabendazole residues. 

IV. Other Considerations 

A. Analytical Enforcement Methodology 

Adequate enforcement methodology 

(spectrophotofluorometric, Methods I, 

A, B and C) is available to enforce the 

tolerance expression. In all of the 

methods, residues are extracted with 

ethyl acetate, and the extracts are 

purified by washing with dilute NaOH 

and/or HCl. 

An high-performance liquid 

chromatography (HPLC) method with 

fluorescence detection (FLD) is available 

for the enforcement of tolerances for 

residues of free and conjugated 

benzimidazole. This method is listed in 

the U.S. EPA Index of Residue 

Analytical Methods under 

thiabendazole as Study No. 93020 

(MRID 43328302). 

In addition, the analytical method 

used in this petition may be used for 

enforcement. This sample is extracted 

and hydrolized and analyzed by liquid 

chromatography/mass spectrometry 

(LC/MS/MS). The method limit of 

quantation (LOQ) is 0.01 ppm, and the 

limit of detection (LOD) is 0.004 ppm. 

The method was adequately validated 

using samples of field corn forage, grain, 

and stover, and sweet corn forage and 

K+CWHR fortified with each analyte at 

0.01, 0.05, and 0.1 ppm. Acceptable 

concurrent recovery data for the method 

were also submitted and achieved. 

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 FFDCA section 408(b)(4). 

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, FFDCA section 408(b)(4) 

requires that EPA explain the reasons 

for departing from the Codex level. 

The Codex has not established any 

MRLs for thiabendazole. 

V. Conclusion 

Therefore, tolerances are established 

for residues of thiabendazole, and its 

metabolites, benzimidazole (free and 

conjugated), [2-(4-thiazolyl) 

benzimidazole], in or on corn grain and 

other corn commodities at 0.01 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, 

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 


erowe on DSK5CLS3C1PROD with RULES
54040 Federal Register / Vol. 75, No. 171 / Friday, September 3, 2010 / Rules and Regulations 

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: August 20, 2010. 

Lois Rossi, 

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 180.242 is amended by 

alphabetically adding the following 

commodities to the table in paragraph 

(a)(1) to read as follows: 

§ 180.242 Thiabendazole; tolerances for 

residues. 

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

Commodity Parts per 

million 

Expiration/ 

Revocation 

Date 

*****

Corn, field, forage ................ 0.01 None 

Corn, field, grain 0.01 None 

Corn, field, stover ................. 0.01 None 

Commodity Parts per 

million 

Expiration/ 

Revocation 

Date 

Corn, pop, forage ................ 0.01 None 

Corn, pop, grain 0.01 None 

Corn, pop, stover ................. 0.01 None 

Corn, sweet, forage ................ 0.01 None 

Corn, sweet, 

kernels plus 

cop with 

husks removed ........... 0.01 None 

Corn, sweet, 

stover ............ 0.01 None 

*****

* * * * * 

[FR Doc. 2010–22121 Filed 9–2–10; 8:45 am] 

BILLING CODE 6560–50–S 

FEDERAL COMMUNICATIONS 

COMMISSION 

47 CFR Part 64 

[CG Docket No. 03–123; DA 10–1235] 

Telecommunications Relay Services 

and Speech-to-Speech Services for 

Individuals With Hearing and Speech 

Disabilities 

AGENCY: Federal Communications 

Commission. 

ACTION: Final rule; extension of waiver. 

SUMMARY: In this document, the 

Commission extends for an additional 

year current waivers of certain 

Telecommunications Relay Services 

(TRS) mandatory minimum standards 

for Video Relay Service (VRS) and 

Internet Protocol Relay (IP Relay). The 

waived TRS mandatory minimum 

standards are: One-line voice carry over 

(VCO); VCO-to-teletypewriter (TTY); 

VCO-to-VCO; one-line hearing carry 

over (HCO); HCO-to-TTY; HCO-to-HCO; 

call release; speech-to-speech (STS); 

pay-per-call (900) calls; types of calls; 

and equal access to interexchange 

carriers requirements. The Commission 

also extends for one year a requirement 

for default Internet-based TRS providers 

that are unable to meet such standards 

for newly-registered Internet-based TRS 

users who port their customer premises 

equipment (CPE) from a former default 

provider. The Commission extends the 

waivers for one year because the record 

demonstrates that it is technologically 

infeasible for VRS and IP Relay 

providers to offer these services at this 

time. All of these waivers are 

conditioned on the filing of a report, 

due April 16, 2011, addressing whether 

it is necessary for the waivers to remain 

in effect. 

DATES: DA 10–1235 became effective on 

June 30, 2010. The waivers of certain 

TRS mandatory minimum standards for 

VRS and IP Relay will expire on July 1, 

2011, or until the Commission addresses 

pending petitions regarding CPE 

portability, which ever comes first. 

ADDRESSES: Federal Communications 

Commission, 445 12th Street, SW., 

Washington, DC 20554. Parties may 

submit documentation related to the 

waivers, identified by [CG Docket No. 

03–123 and/or DA 10–1235], by mail, to 

Dana Wilson, Consumer and 

Governmental Affairs Bureau, Disability 

Rights Office, Room 3–C418. 

FOR FURTHER INFORMATION CONTACT: 

Gregory Hlibok, (202) 559–5158 (voice/ 

videophone), or e-mail 

Gregory.Hlibok@fcc.gov. 

SUPPLEMENTARY INFORMATION: This is a 

summary of the Commission’s 

document DA 10–1235, adopted June 

30, 2010, released June 30, 2010 

extending certain waivers for TRS 

mandatory minimum standards to July 

1, 2011. The full text of document DA 

10–1235, and copies of any 

subsequently filed documents in this 

matter, will be available for public 

inspection and copies during regular 

business hours at the FCC Reference 

Information Center, Portals II, 445 12th 

Street, SW., Room CY–A257, 

Washington, DC 20554. DA 10–1235, 

and copies of subsequently filed 

documents in this matter also may be 

purchased from the Commission’s 

duplicating contractor at Portals II, 445 

12th Street, SW., Room CY–B402, 

Washington, DC 20554. Customers may 

contact the Commission’s duplicating 

contractor at its Web site, http:// 

www.bcpiweb.com or by calling 1–800– 

378–3160. 

To request materials in accessible 

formats for people with disabilities 

(Braille, large print, electronic files, 

audio format), send an e-mail to 

fcc504@fcc.gov or call the Consumer 

and Governmental Affairs Bureau at 

(202) 418–0530 (voice) or (202) 418– 

0432 (TTY). The Commission’s 

document DA 10–1235 can also be 

downloaded in Word and Portable 

Document Format (PDF) at http:// 

www.fcc.gov/cgb/dro.trs.html. 

Synopsis 

One-line VCO, VCO-to-TTY, and 

VCO-to-VCO. One-line VCO is a type of 

traditional TTY-based TRS that can be 

used by persons with a hearing 

disability who can speak. The VCO user 

speaks directly to the other party to the 

call, and the CA types the response back 


erowe on DSK5CLS3C1PROD with RULES