Federal Register / Vol. 62, No. 160 / Tuesday, August 19, 1997 / Rules and Regulations 44089

TEXAS-PM–10 NONATTAINMENT AREAS—Continued

Designated Area

Designation Classification

Date 1 Type Date 1 Type

(Houston 2).

1 limited area in Harris County ................................................................. .................... Unclassifiable .............. ....................

(Aldine).

1 limited area in Harris County ................................................................. .................... Unclassifiable .............. ....................

1 limited area in Galveston County ........................................................... .................... Unclassifiable .............. ....................

Remainder of AQCR ................................................................................. .................... Unclassifiable .............. ....................

AQCR 217:

1 limited area in Bexar County .................................................................. .................... Unclassifiable .............. ....................

Remainder of AQCR ................................................................................. .................... Unclassifiable .............. ....................

AQCR 218 ........................................................................................................ .................... Unclassifiable .............. ....................

1This date is November 15, 1990, unless otherwise noted.

* * * * * * *

[FR Doc. 97–21803 Filed 8–18–97; 8:45 am]

BILLING CODE 6560–50–U

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 180

[OPP–300528; FRL–5737–1]

RIN 2070–AB78

Avermectin; Pesticide Tolerances for

Emergency Exemptions

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Final rule.

SUMMARY: This regulation establishes

time-limited tolerances for the

combined residues of avermectin B1 and

its delta-8,9-isomer in or on celeriac and

spinach. This action is in response to

EPA’s granting of emergency

exemptions under section 18 of the

Federal Insecticide, Fungicide, and

Rodenticide Act authorizing use of the

pesticide on celeriac and spinach. This

regulation establishes a maximum

permissible level for the combined

residues of avermectin B1 and its delta8,9-isomer in or on these food

commodities pursuant to section

408(l)(6) of the Federal Food, Drug, and

Cosmetic Act, as amended by the Food

Quality Protection Act of 1996. These

tolerances will expire and are revoked

on July 31, 1998.

DATES: This regulation is effective

August 19, 1997. Objections and

requests for hearings must be received

by EPA on or before October 20, 1997.

ADDRESSES: Written objections and

hearing requests, identified by the

docket control number, [OPP–300528],

must be submitted to: Hearing Clerk

(1900), Environmental Protection

Agency, Rm. M3708, 401 M St., SW.,

Washington, DC 20460. Fees

accompanying objections and hearing

requests shall be labeled ‘‘Tolerance

Petition Fees’’ and forwarded to: EPA

Headquarters Accounting Operations

Branch, OPP (Tolerance Fees), P.O. Box

360277M, Pittsburgh, PA 15251. A copy

of any objections and hearing requests

filed with the Hearing Clerk identified

by the docket control number, [OPP–

300528], must also be submitted to:

Public Information and Records

Integrity Branch, Information Resources

and Services Division (7506C), Office of

Pesticide Programs, Environmental

Protection Agency, 401 M St., SW.,

Washington, DC 20460. In person, bring

a copy of objections and hearing

requests to Rm. 1132, CM #2, 1921

Jefferson Davis Hwy., Arlington, VA.

A copy of objections and hearing

requests filed with the Hearing Clerk

may also be submitted electronically by

sending electronic mail (e-mail) to: oppdocket@epamail.epa.gov. Copies of

objections and hearing requests must be

submitted as an ASCII file avoiding the

use of special characters and any form

of encryption. Copies of objections and

hearing requests will also be accepted

on disks in WordPerfect 5.1 file format

or ASCII file format. All copies of

objections and hearing requests in

electronic form must be identified by

the docket control number [OPP–

300528]. No Confidential Business

Information (CBI) should be submitted

through e-mail. Electronic copies of

objections and hearing requests on this

rule may be filed online at many Federal

Depository Libraries.

FOR FURTHER INFORMATION CONTACT: By

mail: Daniel Rosenblatt, Registration

Division 7505C, Office of Pesticide

Programs, Environmental Protection

Agency, 401 M St., SW., Washington,

DC 20460. Office location, telephone

number, and e-mail address: Crystal

Mall #2, 1921 Jefferson Davis Hwy.,

Arlington, VA, (703) 308-9375, e-mail:

rosenblatt.dan@epamail.epa.gov.

SUPPLEMENTARY INFORMATION: EPA, on

its own initiative, pursuant to section

408(e) and (l)(6) of the Federal Food,

Drug, and Cosmetic Act (FFDCA), 21

U.S.C. 346a(e) and (l)(6), is establishing

tolerances for the miticide avermectin,

in or on celeriac at 0.05 parts per

million (ppm) and spinach at 0.05 ppm.

These tolerances will expire and are

revoked on July 31, 1998. EPA will

publish a document in the Federal

Register to remove the revoked

tolerances from the Code of Federal

Regulations.

I. Background and Statutory Authority

The Food Quality Protection Act of

1996 (FQPA) (Pub. L. 104–170) was

signed into law August 3, 1996. FQPA

amends both the Federal Food, Drug,

and Cosmetic Act (FFDCA), 21 U.S.C.

301 et seq., and the Federal Insecticide,

Fungicide, and Rodenticide Act

(FIFRA), 7 U.S.C. 136 et seq . The FQPA

amendments went into effect

immediately. Among other things,

FQPA amends FFDCA to bring all EPA

pesticide tolerance-setting activities

under a new section 408 with a new

safety standard and new procedures.

These activities are described below and

discussed in greater detail in the final

rule establishing the time-limited

tolerance associated with the emergency

exemption for use of propiconazole on

sorghum (61 FR 58135, November 13,

1996)(FRL-5572-9).

New section 408(b)(2)(A)(i) of the

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) defines

‘‘safe’’ to mean that ‘‘there is a

reasonable certainty that no harm will
44090 Federal Register / Vol. 62, No. 160 / Tuesday, August 19, 1997 / Rules and Regulations

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) 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. . . .’’

Section 18 of FIFRA authorizes EPA

to exempt any Federal or State agency

from any provision of FIFRA, if EPA

determines that ‘‘emergency conditions

exist which require such exemption.’’

This provision was not amended by

FQPA. EPA has established regulations

governing such emergency exemptions

in 40 CFR part 166.

Section 408(l)(6) of the FFDCA

requires EPA to establish a time-limited

tolerance or exemption from the

requirement for a tolerance for pesticide

chemical residues in food that will

result from the use of a pesticide under

an emergency exemption granted by

EPA under section 18 of FIFRA. Such

tolerances can be established without

providing notice or period for public

comment.

Because decisions on section 18-

related tolerances must proceed before

EPA reaches closure on several policy

issues relating to interpretation and

implementation of the FQPA, EPA does

not intend for its actions on such

tolerance to set binding precedents for

the application of section 408 and the

new safety standard to other tolerances

and exemptions.

II. Emergency Exemption for

Avermectin on Celeriac and Spinach

and FFDCA Tolerances

Celeriac is similar to celery in

appearance and growth habit. It is used

in salads and can be cooked. When

under pressure from the two-spotted

spider mite (Tetranychus urticae),

celeriac plants become stunted and

cosmetically damaged. These problems

can render the commodity

unmarketable. Based on the information

provided by California, EPA concluded

that the pressure posed by the twospotted spider mite on the State’s

celeriac growers represents an urgent

and non-routine situation.

In a separate action, the State of

California requested the use of

avermectin on spinach to control the

leafminer (Liriomyza spp.). Spinach is

grown for the fresh market and the

processed market. Leafminer has grown

increasingly resistant to the registered

insecticide alternatives. Leafminer

damage renders the spinach disfigured

and stunted. Losses would be expected

to be as high as 40% without the use of

avermectin. EPA’s assessment of the

resistance problem and the comparative

efficacy information submitted by the

state is that leafminer poses an urgent

and non-routine problem. Therefore,

EPA has authorized under FIFRA

section 18 the use of avermectin on both

celeriac and spinach for control of the

two-spotted spider mite and leafminer

in California.

As part of its assessment of this

emergency exemption, EPA assessed the

potential risks presented by residues of

avermectin in or on celeriac and

spinach. In doing so, EPA considered

the new safety standard in FFDCA

section 408(b)(2), and EPA decided that

the necessary tolerances under FFDCA

section 408(l)(6) would be consistent

with the new safety standard and with

FIFRA section 18. Consistent with the

need to move quickly on the emergency

exemption in order to address an urgent

non-routine situation and to ensure that

the resulting food is safe and lawful,

EPA is issuing these tolerances without

notice and opportunity for public

comment under section 408(e), as

provided in section 408(l)(6). Although

these tolerances will expire and are

revoked on July 31, 1998, under FFDCA

section 408(l)(5), residues of the

pesticide not in excess of the amounts

specified in the tolerance remaining in

or on celeriac or spinach after that date

will not be unlawful, provided the

pesticide is applied in a manner that

was lawful under FIFRA. EPA will take

action to revoke these tolerances earlier

if any experience with, scientific data

on, or other relevant information on this

pesticide indicate that the residues are

not safe.

Because these tolerances are being

approved under emergency conditions

EPA has not made any decisions about

whether avermectin meets EPA’s

registration requirements for use on

celeriac or spinach or whether a

permanent tolerance for these uses

would be appropriate. Under these

circumstances, EPA does not believe

that these tolerances serve as a basis for

registration of avermectin by a State for

special local needs under FIFRA section

24(c). Nor do these tolerances serve as

the basis for any State other than

California to use this pesticide on these

crops under section 18 of FIFRA

without following all provisions of

section 18 as identified in 40 CFR part

166. For additional information

regarding the emergency exemptions for

avermectin, contact the Agency’s

Registration Division at the address

provided above.

III. Risk Assessment and Statutory

Findings

EPA performs a number of analyses to

determine the risks from aggregate

exposure to pesticide residues. First,

EPA determines the toxicity of

pesticides based primarily on

toxicological studies using laboratory

animals. These studies address many

adverse health effects, including (but

not limited to) reproductive effects,

developmental toxicity, toxicity to the

nervous system, and carcinogenicity.

Second, EPA examines exposure to the

pesticide through the diet (e.g., food and

drinking water) and through exposures

that occur as a result of pesticide use in

residential settings.

A. Toxicity

1. Threshold and non-threshold

effects. For many animal studies, a dose

response relationship can be

determined, which provides a dose that

causes adverse effects (threshold effects)

and doses causing no observed effects

(the ‘‘no-observed effect level’’ or

‘‘NOEL’’).

Once a study has been evaluated and

the observed effects have been

determined to be threshold effects, EPA

generally divides the NOEL from the

study with the lowest NOEL by an

uncertainty factor (usually 100 or more)

to determine the Reference Dose (RfD).

The RfD is a level at or below which

daily aggregate exposure over a lifetime

will not pose appreciable risks to

human health. An uncertainty factor

(sometimes called a ‘‘safety factor’’) of

100 is commonly used since it is

assumed that people may be up to 10

times more sensitive to pesticides than

the test animals, and that one person or

subgroup of the population (such as

infants and children) could be up to 10

times more sensitive to a pesticide than

another. In addition, EPA assesses the

potential risks to infants and children

based on the weight of the evidence of

the toxicology studies and determines

whether an additional uncertainty factor

is warranted. Thus, an aggregate daily

exposure to a pesticide residue at or

below the RfD (expressed as 100% or

less of the RfD) is generally considered

acceptable by EPA. EPA generally uses

the RfD to evaluate the chronic risks

posed by pesticide exposure. For shorter

term risks, EPA calculates a margin of

exposure (MOE) by dividing the

estimated human exposure into the

NOEL from the appropriate animal

study. Commonly, EPA finds MOEs
Federal Register / Vol. 62, No. 160 / Tuesday, August 19, 1997 / Rules and Regulations 44091

lower than 100 to be unacceptable. This

100-fold MOE is based on the same

rationale as the 100-fold uncertainty

factor.

Lifetime feeding studies in two

species of laboratory animals are

conducted to screen pesticides for

cancer effects. When evidence of

increased cancer is noted in these

studies, the Agency conducts a weight

of the evidence review of all relevant

toxicological data including short-term

and mutagenicity studies and structure

activity relationship. Once a pesticide

has been classified as a potential human

carcinogen, different types of risk

assessments (e.g., linear low dose

extrapolations or MOE calculation based

on the appropriate NOEL) will be

carried out based on the nature of the

carcinogenic response and the Agency’s

knowledge of its mode of action.

2. Differences in toxic effect due to

exposure duration. The toxicological

effects of a pesticide can vary with

different exposure durations. EPA

considers the entire toxicity data base,

and based on the effects seen for

different durations and routes of

exposure, determines which risk

assessments should be done to assure

that the public is adequately protected

from any pesticide exposure scenario.

Both short and long durations of

exposure are always considered.

Typically, risk assessments include

‘‘acute’’, ‘‘short-term’’, ‘‘intermediate

term’’, and ‘‘chronic’’ risks. These

assessments are defined by the Agency

as follows.

Acute risk, by the Agency’s definition,

results from 1-day consumption of food

and water, and reflects toxicity which

could be expressed following a single

oral exposure to the pesticide residues.

High end exposure to food and water

residues are typically assumed.

Short-term risk results from exposure

to the pesticide for a period of 1-7 days,

and therefore overlaps with the acute

risk assessment. Historically, this risk

assessment was intended to address

primarily dermal and inhalation

exposure which could result, for

example, from residential pesticide

applications. However, since enaction of

FQPA, this assessment has been

expanded to include both dietary and

non-dietary sources of exposure, and

will typically consider exposure from

food, water, and residential uses when

reliable data are available. In this

assessment, risks from average food and

water exposure, and high-end

residential exposure, are aggregated.

High-end exposures from all 3 sources

are not typically added because of the

very low probability of this occurring in

most cases, and because the other

conservative assumptions built into the

assessment assure adequate protection

of public health. However, for cases in

which high-end exposure can

reasonably be expected from multiple

sources (e.g. frequent and widespread

homeowner use in a specific

geographical area), multiple high-end

risks will be aggregated and presented

as part of the comprehensive risk

assessment/characterization. Since the

toxicological endpoint considered in

this assessment reflects exposure over a

period of at least 7 days, an additional

degree of conservatism is built into the

assessment; i.e., the risk assessment

nominally covers 1-7 days exposure,

and the toxicological endpoint/NOEL is

selected to be adequate for at least 7

days of exposure. (Toxicity results at

lower levels when the dosing duration

is increased.)

Intermediate-term risk results from

exposure for 7 days to several months.

This assessment is handled in a manner

similar to the short-term risk

assessment.

Chronic risk assessment describes risk

which could result from several months

to a lifetime of exposure. For this

assessment, risks are aggregated

considering average exposure from all

sources for representative population

subgroups including infants and

children.

B. Aggregate Exposure

In examining aggregate exposure,

FFDCA section 408 requires that EPA

take into account available and reliable

information concerning exposure from

the pesticide residue in the food in

question, residues in other foods for

which there are tolerances, residues in

groundwater or surface water that is

consumed as drinking water, and other

non-occupational exposures through

pesticide use in gardens, lawns, or

buildings (residential and other indoor

uses). Dietary exposure to residues of a

pesticide in a food commodity are

estimated by multiplying the average

daily consumption of the food forms of

that commodity by the tolerance level or

the anticipated pesticide residue level.

The Theoretical Maximum Residue

Contribution (TMRC) is an estimate of

the level of residues consumed daily if

each food item contained pesticide

residues equal to the tolerance. In

evaluating food exposures, EPA takes

into account varying consumption

patterns of major identifiable subgroups

of consumers, including infants and

children. The TMRC is a ‘‘worst case’’

estimate since it is based on the

assumptions that food contains

pesticide residues at the tolerance level

and that 100% of the crop is treated by

pesticides that have established

tolerances. If the TMRC exceeds the RfD

or poses a lifetime cancer risk that is

greater than approximately one in a

million, EPA attempts to derive a more

accurate exposure estimate for the

pesticide by evaluating additional types

of information (anticipated residue data

and/or percent of crop treated data)

which show, generally, that pesticide

residues in most foods when they are

eaten are well below established

tolerances.

Percent of crop treated estimates are

derived from federal and private market

survey data. Typically, a range of

estimates are supplied and the upper

end of this range is assumed for the

exposure assessment. By using this

upper end estimate of percent of crop

treated, the Agency is reasonably certain

that exposure is not understated for any

significant subpopulation group.

Further, regional consumption

information is taken into account

through EPA’s computer-based model

for evaluating the exposure of

significant subpopulations including

several regional groups, to pesticide

residues. For this pesticide, the

population subgroup (of highest

concern, females 13 years and older,)

was not regionally based.

IV. Aggregate Risk Assessment and

Determination of Safety

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

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 avermectin and to make a

determination on aggregate exposure,

consistent with section 408(b)(2), for

time-limited tolerances for residues of

avermectin on celeriac at 0.05 ppm and

spinach at 0.05 ppm. EPA’s assessment

of the dietary exposures and risks

associated with establishing the

tolerances 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 nature of the

toxic effects caused by avermectin are

discussed below.

1. Acute toxicity. For acute dietary

risk assessment, EPA recommends use

of a NOEL of 0.06 mg/kg/day from the

developmental toxicity study in mice.

The effects observed at the Lowest Effect
44092 Federal Register / Vol. 62, No. 160 / Tuesday, August 19, 1997 / Rules and Regulations

Level (LEL) of 0.10 mg/kg/day involved

cleft palate. For the purposes of this

action, an MOE of 300 is considered

necessary to be adequately protective for

dietary (food only) exposure.

2. Short - and intermediate - term

toxicity. For short- and intermediateterm MOE calculations, EPA

recommends use of the developmental

NOEL of 0.2 mg/kg/day from the oral

developmental toxicity study in mice.

At the LEL of 0.4 mg/kg/day, there was

an increased incidence of cleft palate.

3. Chronic toxicity. EPA has

established the RfD for avermectin at

0.0004 milligrams/kilogram/day (mg/kg/

day). This RfD is based on a 2-

generation rat reproductive toxicity

study with a NOEL of 0.12 mg/kg/day

and an uncertainty factor of 300. In

addition to the uncertainty factor of 100

for inter- and intra-species variations, a

Modifying Factor (MF) of 3 was used.

The MF was used because of the

severity of the effects (pup deaths) and

the steep dose-response curve. At the

LEL of 0.40 mg/kg/day, there was

decreased pup body weight and

viability during lactation as well as an

increased incidence of retinal rosettes in

F2b weanlings.

4. Carcinogenicity. Avermectin has

been classified by EPA as a Group E

(‘‘evidence of non-carcinogenicity for

humans’’) chemical. Therefore, a cancer

risk assessment is not needed.

B. Exposures and Risks

1. From food and feed uses.

Tolerances have been established (40

CFR 180.449) for the combined residues

of avermectin B1 and its delta-8,9-

isomer, in or on a variety of raw

agricultural commodities, ranging from

0.005 ppm in cottonseed to 0.05 ppm in

celery. Risk assessments were

conducted by EPA to assess dietary

exposures and risks from avermectin as

follows:

i. Acute exposure and risk. Acute

dietary 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 one day or single exposure. In a

separate and earlier registration action,

the Agency required the development of

more highly refined residue and

exposure information to support the

pesticide. In response, in October 1996,

EPA received a Monte Carlo analysis for

all uses of avermectin at that time. Since

that analysis was generated before these

section 18 actions were submitted, EPA

does not have information on acute

exposures for spinach and celeriac. In

addition, given the limitations of EPA’s

dietary analysis system, EPA does not

have consumption data on the minor

crop celeriac. Further, the Agency does

not have the capability to independently

perform Monte Carlo analysis.

Therefore, the acute exposure

assessment for this action does not

include data associated with the

consumption of spinach and celeriac.

With the above exceptions, data

available to EPA suggest a high-end

exposure estimate of 0.000078 mg/kg/

day for uses of avermectin. This results

in a dietary (food only) MOE of 769 for

females 13 years and older, the

population subgroup of concern. In

EPA’s judgement, the addition of

spinach and celeriac to acute exposure

and risk calculations would not produce

acute risks (food only) that exceed a

level of concern.

ii. Chronic exposure and risk. As

mentioned above, the commodity

celeriac is not uniquely identified in the

Agency’s food consumption data

system. However, EPA reviewed

information that establishes chronic

dietary exposure estimates for

avermectin. This chronic dietary (food

only) risk assessment used anticipated

residue refinement for commodities

with tolerances for avermectin, but did

not incorporate any refinement for

percent of crop treated (default of 100%

was assumed). Therefore, the resulting

exposure estimates should be viewed as

partially refined; further refinement for

percent of crop treated would result in

lower dietary exposure estimates. The

existing avermectin tolerances plus the

proposed tolerances associated with the

section 18 use of the chemical result in

an Anticipated Residue Contribution

that ranges from 5 percent of the RfD for

the U.S. population to 12% of the RfD

for non-nursing infants less than a year

old.

2. From drinking water. In examining

aggregate exposure, FQPA directs EPA

to consider available information

concerning exposures from the pesticide

residues in food and all other nonoccupational exposures. The primary

non-food sources of exposure the

Agency looks at include drinking water

(whether from ground or surface water),

and exposure through pesticide use in

gardens, lawns, or buildings (residential

and other indoor uses). Based on data

available to EPA, avermectin is

moderately persistent and not very

mobile. It is not likely to be found

extensively in ground water, but could

be found in surface water. Under

anaerobic conditions in the absence of

light, avermectin does not degrade. No

Health Advisories or Maximum

Contaminant Levels for avermectin in

drinking water have been established.

Because the Agency lacks sufficient

water-related exposure data to complete

a comprehensive drinking water risk

assessment for many pesticides, EPA

has commenced and nearly completed a

process to identify a reasonable yet

conservative bounding figure for the

potential contribution of water-related

exposure to the aggregate risk posed by

a pesticide. In developing the bounding

figure, EPA estimated residue levels in

water for a number of specific pesticides

using various data sources. The Agency

then applied the estimated residue

levels, in conjunction with appropriate

toxicological endpoints (RfD’s or acute

dietary NOEL’s) and assumptions about

body weight and consumption, to

calculate, for each pesticide, the

increment of aggregate risk contributed

by consumption of contaminated water.

While EPA has not yet pinpointed the

appropriate bounding figure for

exposure from contaminated water, the

ranges the Agency is continuing to

examine are all below the level that

would cause avermectin to exceed the

RfD if the tolerance being considered in

this document were granted. The

Agency has therefore concluded that the

potential exposures associated with

avermectin in water, even at the higher

levels the Agency is considering as a

conservative upper bound, would not

prevent the Agency from determining

that there is a reasonable certainty of no

harm if the tolerance is granted.

3. From non-dietary exposure.

Avermectin is currently registered for

use on the following residential nonfood sites: ornamental crops

(herbaceous and woody), turf,

households (indoor and outdoor), and

non-food areas of food handling

establishments.

i. Chronic exposure and risk. Given

the uses for avermectin, a chronic nondietary exposure scenario would not be

expected.

ii. Short- and intermediate-term

exposure and risk. EPA assessed indoor

residential risk characterization data to

evaluate short- and intermediate-term

exposure and risk. Based on the

assumptions for exposure total oral,

dermal, and respiratory estimated

absorbed daily exposure could total

.00023 mg/kg/day. This correlates to a

total short- and intermediate-term

indoor residential MOE of 870 for the

U.S. population.

4. Cumulative exposure to substances

with common mechanism of toxicity.

Section 408(b)(2)(D)(v) 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.’’
Federal Register / Vol. 62, No. 160 / Tuesday, August 19, 1997 / Rules and Regulations 44093

The Agency believes that ‘‘available

information’’ in this context might

include not only toxicity, chemistry,

and exposure data, but also scientific

policies and methodologies for

understanding common mechanisms of

toxicity and conducting cumulative risk

assessments. For most pesticides,

although the Agency has some

information in its files that may turn out

to be helpful in eventually determining

whether a pesticide shares a common

mechanism of toxicity with any other

substances, EPA does not at this time

have the methodologies to resolve the

complex scientific issues concerning

common mechanism of toxicity in a

meaningful way. EPA has begun a pilot

process to study this issue further

through the examination of particular

classes of pesticides. The Agency hopes

that the results of this pilot process will

increase the Agency’s scientific

understanding of this question such that

EPA will be able to develop and apply

scientific principles for better

determining which chemicals have a

common mechanism of toxicity and

evaluating the cumulative effects of

such chemicals. The Agency anticipates,

however, that even as its understanding

of the science of common mechanisms

increases, decisions on specific classes

of chemicals will be heavily dependent

on chemical specific data, much of

which may not be presently available.

Although at present the Agency does

not know how to apply the information

in its files concerning common

mechanism issues to most risk

assessments, there are pesticides as to

which the common mechanism issues

can be resolved. These pesticides

include pesticides that are

toxicologically dissimilar to existing

chemical substances (in which case the

Agency can conclude that it is unlikely

that a pesticide shares a common

mechanism of activity with other

substances) and pesticides that produce

a common toxic metabolite (in which

case common mechanism of activity

will be assumed).

EPA does not have, at this time,

available data to determine whether

avermectin has a common mechanism

of toxicity with other substances or how

to include this pesticide in a cumulative

risk assessment. Unlike other pesticides

for which EPA has followed a

cumulative risk approach based on a

common mechanism of toxicity,

avermectin does not appear to produce

a toxic metabolite produced by other

substances. For the purposes of this

tolerance action, therefore, EPA has not

assumed that avermectin has a common

mechanism of toxicity with other

substances.

C. Aggregate Risks and Determination of

Safety for U.S. Population

1. Acute risk. The population

subgroup of concern is females 13 years

and older. The MOE for this subgroup

from food exposures is 769. Despite the

potential for exposures to avermectin

from drinking water and spinach, EPA

does not expect the acute aggregate risk

to exceed levels of concern.

2. Chronic risk. Using the ARC

exposure assumptions described above,

EPA has concluded that aggregate

exposure to avermectin from food will

utilize 5 percent of the RfD for the U.S.

population. The existing avermectin

tolerances plus the tolerances associated

with this action result in an Anticipated

Residue Contribution that is equivalent

to 5% of the RfD. EPA generally has no

concern for exposures below 100% of

the RfD because the RfD represents the

level at or below which daily aggregate

dietary exposure over a lifetime will not

pose appreciable risks to human health.

Despite the potential for exposure to

avermectin in drinking water, EPA does

not expect the aggregate exposure to

exceed 100% of the RfD. EPA concludes

that there is a reasonable certainty that

no harm will result from aggregate

exposure to avermectin residues.

3. Short- and intermediate-term risk.

Short- and intermediate-term aggregate

exposure takes into account chronic

dietary food and water (considered to be

a background exposure level) plus

indoor and outdoor residential exposure

As referenced above, for short- and

intermediate-term exposures, EPA

assessed information that addresses this

topic in relation to human exposure

associated with residential use through

oral, dermal, and respiratory exposures.

The anticipated MOE was 803 for the

U.S. population. EPA considers this

MOE to be adequately protective.

D. Aggregate Cancer Risk for U.S.

Population

Avermectin has been classified as a

Group E ‘‘evidence of noncarcinogenicity for humans’’ chemical

by EPA. Therefore, a cancer risk

assessment is not needed.

E. Aggregate Risks and Determination of

Safety for Infants and Children

1. Safety factor for infants and

children — a. In general. In assessing

the potential for additional sensitivity of

infants and children to residues of

avermectin, EPA considered data from

developmental toxicity studies in the

mouse, rat and rabbit and a twogeneration reproduction study in the rat.

The developmental toxicity studies are

designed to evaluate adverse effects on

the developing organism resulting from

maternal pesticide exposure during

gestation. Reproduction studies provide

information relating to effects from

exposure to the pesticide on the

reproductive capability of mating

animals and data on systemic toxicity.

FFDCA section 408 provides that EPA

shall apply an additional tenfold margin

of safety for infants and children in the

case of threshold effects to account for

pre-and post-natal toxicity and the

completeness of the database unless

EPA determines that a different margin

of safety will be safe for infants and

children. Margins of safety are

incorporated into EPA risk assessments

either directly through use of a MOE

analysis or through using uncertainty

(safety) factors in calculating a dose

level that poses no appreciable risk to

humans. EPA believes that reliable data

support using the standard factor

(usually 100 for combined inter- and

intra-species variability)) and not the

additional tenfold factor when EPA has

a complete data base under existing

guidelines and when the severity of the

effect in infants or children or the

potency or unusual toxic properties of a

compound do not raise concerns

regarding the adequacy of the standard

safety factor.

b. Developmental toxicity studies. In

the mouse developmental toxicity

analysis, the maternal (systemic) NOEL

was 0.05 mg/kg/day based on mortality

at the lowest observed effect level

(LOEL) of 0.075 mg/kg/day. The

developmental (fetal) NOEL was 0.2 mg/

kg/day based on cleft palate at the LOEL

of 0.4 mg/kg/day. The Delta-8,9-Isomer

was also tested for developmental

toxicity in the mouse. In the mouse

developmental study for the isomer, the

maternal (systemic) NOEL was 0.10 mg/

kg/day, based on mortality at the LOEL

of 0.20 mg/kg/day. The developmental

(fetal) NOEL was 0.06 mg/kg/day, based

on cleft palate at the LOEL of 0.10 mg/

kg/day.

In the rat developmental study, the

maternal (systemic) NOEL was greater

than or equal to 1.6 mg/kg/day. The

developmental (fetal) NOEL was 1.6 mg/

kg/day. In the rabbit developmental

study, the maternal (systemic) NOEL

was 1.0 mg/kg/day, based on decreased

body weight and decreased food and

water consumption at the LOEL of 2.0

mg/kg/day. The developmental (fetal)

NOEL was 1.0 mg/kg/day, based on

clubbed foot, and delayed ossification of

sternebrae, metacarpals, and phalanges

at the LOEL of 2.0 mg/kg/day.

c. Reproductive toxicity study. In the

2-generation rat reproductive toxicity

study, the maternal (systemic) NOEL

was 0.4 mg/kg/day (HDT). The
44094 Federal Register / Vol. 62, No. 160 / Tuesday, August 19, 1997 / Rules and Regulations

developmental (pup) NOEL was 1.2 mg/

kg/day, based on decreased viability

indices, decreased pup body weight,

and retinal fold in weanlings at the

LOEL of 0.4 mg/kg/day. The

reproductive (pup) NOEL was 0.4 mg/

kg/day (HDT).

d. Pre- and post-natal sensitivity. Both

the delta-8,9-isomer of avermectin and

avermectin per se exhibit cleft palate in

CF1 mouse developmental studies. The

NOEL for cleft plate for the delta-8,9-

isomer is 0.06 mg/kg/day with the LOEL

at 0.10 mg/kg/day. For avermectin per

se, the NOEL for cleft palate is 0.2 mg/

kg/day with the LOEL at 0.4 mg/kg/day.

Therefore, pre-natal sensitivity to the

regulated residue for avermectin is

demonstrated when considering these

developmental findings in the CF1

Mouse. An additional 3-fold uncertainty

factor has been added to account for

these developmental findings.

An acute dietary risk assessment is

needed based on the results of the

developmental study in mice with the

delta-8,9-isomer. This risk assessment

will evaluate acute dietary risk to

females 13 years and older. For the

purpose of the section 18, an MOE of

300 is considered necessary to be

adequately protective for dietary (food

only) exposure.

To evaluate the pre-natal risks, the

acute dietary MOE calculations for

females 13 years and older has been

conducted using the lowest NOEL for all

developmental studies for cleft palate

(0.06 mg/kg/day).

The results of the rat reproduction

study required that a Modifying Factor

of 3 be added to the usual uncertainty

factor of 100 used for the RfD. EPA used

this Modifying Factor in developing this

analysis. Typically, the Agency uses a

modifying factor of 10 when no study is

available and uses a modifying factor of

3 when a study exists which shows

effects in the fetus before they appear in

the parent.

2. Acute risk. The acute dietary MOE

for females 13 years and older (accounts

for both maternal and fetal exposure) is

769. This MOE calculation is based on

the developmental NOEL in mice of

0.06 mg/kg/day. This estimate is based

on Monte Carlo modeling incorporating

anticipated residue and percent of crop

treated refinement. In EPA’s judgement,

the large acute dietary MOE provides

assurance that there is a reasonable

certainty of no harm for females 13

years and older and the pre-natal

development of infants.

3. Chronic risk. Using the

conservative exposure assumptions

described above, EPA has concluded

that aggregate exposure to avermectin

from food will utilize 12% of the RfD for

non-nursing infants less than a year old

and 8% of the RfD for children 1-6 years

old. EPA generally has no concern for

exposures below 100% of the RfD

because the RfD represents the level at

or below which daily aggregate dietary

exposure over a lifetime will not pose

appreciable risks to human health.

Despite the potential for exposure to

avermectin in drinking water, EPA does

not expect the aggregate exposure to

exceed 100% of the RfD. EPA concludes

that there is a reasonable certainty that

no harm will result to infants and

children from aggregate exposure to

avermectin residues.

4. Short- or intermediate-term risk.

The anticipated MOEs for short- and

intermediate-term exposures for infants

and children do not pose a level of

concern. The calculated MOEs range

from 716 for non-nursing infants to 787

for children 7-12 years old.

V. Other Considerations

A. Metabolism In Plants and Animals

The nature of the residue in plants

and animals is adequately understood.

As cited at 40 CFR 180.449, the

regulable residues are avermectin B1

and its delta-8,9-isomer.

B. Analytical Enforcement Methodology

Merck Method 10001, rev. 2, an

HPLC-fluorescence method, may be

used to enforce the tolerance

expression. This method has been

submitted to FDA for publication in

PAM Volume II.

C. Magnitude of Residues

Residues of avermectin B1 and its

delta-8,9-isomer are not expected to

exceed 0.05 ppm on celeriac or spinach

as a result of these section 18 requests.

Secondary residues are not expected in

animal commodities as no feed items

are associated with these section 18

uses. .

D. International Residue Limits

No Codex MRLs have been

established for avermectin residues on

celeriac or spinach.

VI. Conclusion

Therefore, the tolerances are

established for avermectin B1 and its

delta-8,9-isomer in celeriac at 0.05 ppm

and spinach at 0.05 ppm.

VII. Objections and Hearing Requests

The new FFDCA section 408(g)

provides essentially the same process

for persons to ‘‘object’’ to a tolerance

regulation issued by EPA under new

section 408(e) and (l)(6) as was provided

in the old section 408 and in section

409. However, the period for filing

objections is 60 days, rather than 30

days. EPA currently has procedural

regulations which govern the

submission of objections and hearing

requests. These regulations will require

some modification to reflect the new

law. However, until those modifications

can be made, EPA will continue to use

those procedural regulations with

appropriate adjustments to reflect the

new law.

Any person may, by October 20, 1997

file written objections to any aspect of

this regulation and may also request a

hearing on those objections. Objections

and hearing requests must be filed with

the Hearing Clerk, at the address given

above (40 CFR 178.20). A copy of the

objections and/or hearing requests filed

with the Hearing Clerk should be

submitted to the OPP docket for this

rulemaking. The objections submitted

must specify the provisions of the

regulation deemed objectionable and the

grounds for the objections (40 CFR

178.25). Each objection must be

accompanied by the fee prescribed by

40 CFR 180.33(i). If a hearing is

requested, the objections must include a

statement of the factual issues on which

a hearing is requested, the requestor’s

contentions on such issues, and a

summary of any evidence relied upon

by the requestor (40 CFR 178.27). A

request for a hearing will be granted if

the Administrator determines that the

material submitted shows the following:

There is genuine and substantial issue

of fact; there is a reasonable possibility

that available evidence identified by the

requestor would, if established, resolve

one or more of such issues in favor of

the requestor, taking into account

uncontested claims or facts to the

contrary; and resolution of the factual

issues in the manner sought by the

requestor would be adequate to justify

the action requested (40 CFR 178.32).

Information submitted in connection

with an objection or hearing request

may be claimed confidential by marking

any part or all of that information as

Confidential Business Information (CBI).

Information so marked will not be

disclosed except in accordance with

procedures set forth in 40 CFR part 2.

A copy of the information that does not

contain CBI must be submitted for

inclusion in the public record.

Information not marked confidential

may be disclosed publicly by EPA

without prior notice.

VIII. Public Docket

EPA has established a record for this

rulemaking under docket control

number [OPP–300528] (including any
Federal Register / Vol. 62, No. 160 / Tuesday, August 19, 1997 / Rules and Regulations 44095

comments and data submitted

electronically). A public version of this

record, including printed, paper

versions of electronic comments, which

does not include any information

claimed as CBI, is available for

inspection from 8:30 a.m. to 4 p.m.,

Monday through Friday, excluding legal

holidays. The public record is located in

Room 1132 of the Public Information

and Records Integrity Branch,

Information Resources and Services

Division (7506C), Office of Pesticide

Programs, Environmental Protection

Agency, Crystal Mall #2, 1921 Jefferson

Davis Hwy., Arlington, VA.

Electronic comments may be sent

directly to EPA at:

opp-docket@epamail.epa.gov.

Electronic comments must be

submitted as an ASCII file avoiding the

use of special characters and any form

of encryption.

The official record for this

rulemaking, as well as the public

version, as described above will be kept

in paper form. Accordingly, EPA will

transfer any copies of objections and

hearing requests received electronically

into printed, paper form as they are

received and will place the paper copies

in the official rulemaking record which

will also include all comments

submitted directly in writing. The

official rulemaking record is the paper

record maintained at the Virginia

address in ‘‘ADDRESSES’’ at the

beginning of this document.

IX. Regulatory Assessment

Requirements

This final rule establishes tolerances

under FFDCA section 408(1)(6). 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). 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., or impose any

enforceable duty or contain any

unfunded mandate as described under

Title II of the Unfunded Mandates

Reform Act of 1995 (UMRA) (Pub. L.

104-4). Nor does it require any prior

consultation as specified by Executive

Order 12875, entitled Enhancing the

Intergovernmental Partnership (58 FR

58093, October 28, 1993), or special

considerations as required by Executive

Order 12898, entitled Federal Actions to

Address Environmental Justice in

Minority Populations and Low-Income

Populations (59 FR 7629, February 16,

1994), or require OMB review in

accordance with Executive Order 13045,

entitled Protection of Children from

Environmental Health Risks and Safety

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

In addition, since these tolerances and

exemptions that are established under

FFDCA section 408 (d), such as the

tolerances 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. Nevertheless, the

Agency has previously assessed whether

establishing tolerances, exemptions

from tolerances, raising tolerance levels

or expanding exemptions might

adversely impact small entities and

concluded, as a generic matter, that

there is no adverse economic impact.

The factual basis for the Agency’s

generic certification for tolerance

actions published on May 4, 1981 (46

FR 24950), and was provided to the

Chief Counsel for Advocacy of the Small

Business Administration.

X. Submission to Congress and the

General Accounting Office

Under 5 U.S.C. 801(a)(1)(A), as added

by the Small Business Regulatory

Enforcement Fairness Act of 1996, the

Agency has submitted 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 General

Accounting Office prior to publication

of this rule in today’s Federal Register.

This 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 11, 1997.

James Jones,

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. 3 46a and 371.

2. Section 180.449 is revised to read

as follows:

§ 180.449 Avermectin B1 and its delta-8,9-

isomer; tolerances for residues.

(a) General. Tolerances are

established for the combined residues of

the insecticide avermectin (a mixture of

avermectins containing greater than or

equal to 80% avermectin B1a (5-Odemethyl avermectin Al) and less than

or equal to 20% avermectin Blb (5-Odemethyl-25-de(1-methylpropyl)-25-(1-

methylethyl) avermectin Al)) and its

delta-8,9-isomer in or on the following

commodities:

Commodity Parts per

million

Expiration/

revocation

date

Almonds ............ 0.005 None

Apples ............... 0.020 None

Cattle, fat ........... 0.015 9/1/99

Cattle, mbyp ...... 0.02 9/1/99

Cattle, meat ....... 0.02 9/1/99

Celery ................ 0.05 None

Citrus, dried pulp 0.10 9/1/99

Citrus, oil ........... 0.10 9/1/99

Citrus whole fruit 0.02 9/1/99

Cottonseed ........ 0.005 9/1/99

Cucurbits (cucumbers,

mellons, and

squashes) ...... 0.005 None

Hops, dried ........ 0.2 9/1/99

Lettuce, head .... 0.05 None

Milk .................... 0.005 9/1/99

Pears ................. 0.02 None

Peppers, bell ..... 0.01 None

Potatoes ............ 0.005 9/1/99

Strawberry ......... 0.02 None

Tomatoes, fresh 0.01 None

Walnuts ............. 0.005 None

(b) Section 18 emergency exemptions.

Time-limited tolerances are established

for residues of the miticide avermectin

B1 and its delta-8,9-isomer in

connection with use of the pesticide

under section 18 emergency exemptions

granted by EPA. These tolerances will

expire and are revoked on the dates

specified in the following table:

Commodity Parts per

million

Expiration/

revocation

date

Celeriac ............. 0.05 7/31/98

Spinach ............. 0.05 7/31/98

(c) Tolerances with regional

registrations. [Reserved]

(d) Indirect or inadvertent residues.

[Reserved]

[FR Doc. 97–21924 Filed 8–18–97; 8:45 am]

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