

[Federal Register: August 29, 2007 (Volume 72, Number 167)]
[Rules and Regulations]               
[Page 49646-49651]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29au07-2]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2005-0157; FRL-8143-9]

 
Propylene Oxide; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for residues of 
propylene oxide and for the reaction product, propylene chlorohydrin, 
in or on fig; grape, raisin; and plum, prune, dried, when used as a 
post-harvest fumigant. This rule additionally removes all directions 
for use currently listed in 40 CFR 180.491. Aberco, Incorporated 
requested these tolerances under the Federal Food, Drug, and Cosmetic 
Act (FFDCA).

DATES: This regulation is effective August 29, 2007. Objections and 
requests for hearings must be received on or before October 29, 2007, 
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-2005-0157. To access the 
electronic docket, go to http://www.regulations.gov, select ``Advanced 

Search,'' then ``Docket Search.'' Insert the docket ID number where 
indicated and select the ``Submit'' button. Follow the instructions on 
the regulations.gov web site to view the docket index or access 
available documents. All documents in the docket are listed in the 
docket index available in regulations.gov. Although listed in the 
index, some information is not publicly available, e.g., Confidential 
Business Information (CBI) or other information whose disclosure is 
restricted by statute. Certain other material, such as copyrighted 
material, is not placed on the Internet and will be publicly available 
only in hard copy form. Publicly available docket materials are 
available in the electronic docket at http://www.regulations.gov, or, 

if only available in hard copy, at the OPP Regulatory Public Docket in 
Rm. S-4400, One Potomac Yard (South Bldg.), 2777 S. Crystal Dr., 
Arlington, VA. The Docket Facility is open from 8:30 a.m. to 4 p.m., 
Monday through Friday, excluding legal holidays. The Docket Facility 
telephone number is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: Tony Kish, Registration Division 
(7505P), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 308-9443; e-mail address: kish.tony@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), e.g., agricultural 
workers; greenhouse, nursery, and floriculture workers; farmers.
     Animal production (NAICS code 112), e.g., cattle ranchers 
and farmers, dairy cattle farmers, livestock farmers.
     Food manufacturing (NAICS code 311), e.g., agricultural 
workers; farmers; greenhouse, nursery, and floriculture workers; 
ranchers; pesticide applicators.
     Pesticide manufacturing (NAICS code 32532), e.g., 
agricultural workers; commercial applicators; farmers; greenhouse, 
nursery, and floriculture workers; residential users.
    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

[[Page 49647]]

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 Access Electronic Copies of this Document?

    In addition to accessing an electronic copy of this Federal 
Register document through the electronic docket at http://www.regulations.gov
, you may access this Federal Register document 

electronically through the EPA Internet under the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr. You may also access a 

frequently updated electronic version of EPA's tolerance regulations at 
40 CFR part 180 through the Government Printing Office's pilot e-CFR 
site at http://www.gpoaccess.gov/ecfr.


C. Can I File an Objection or Hearing Request?

    Under section 408(g) of the FFDCA, 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-2005-0157 in the subject line on the first page of 
your submission. All requests must be in writing, and must be mailed or 
delivered to the Hearing Clerk as required by 40 CFR part 178 on or 
before October 29, 2007.
    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 that is described in ADDRESSES. Information not marked 
confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA 
without prior notice. Submit this copy, identified by docket ID number 
EPA-HQ-OPP-2005-0157, 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'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. Petition for Tolerance

    In the Federal Register of June 27, 2007 (72 FR 35242) (FRL-8133-
4), 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 
5F6904) by Aberco, Incorporated, 9430 Lanham-Severn Road, Seabrook, MD 
20706. The petition requested that 40 CFR 180.491 be amended by 
establishing a tolerance for residues of the post-harvest fumigant 
propylene oxide, in or on fig; grape, raisin; and plum, prune, dried at 
3.0; 1.0; and 2.0; respectively parts per million (ppm); and that the 
directions for use currently listed in 40 CFR 180.491 under paragraphs 
(a)(2) and (a)(4) be deleted. The petition also identified propylene 
chlorohydrin as a metabolite and included an enforcement method for 
determination of residues of propylene oxide, propylene chlorohydrin, 
and propylene bromohydrin in nutmeats, cocoa, and dried spices. That 
notice referenced a summary of the petition prepared by Aberco, 
Incorporated, the registrant, which is available to the public in the 
docket, http://www.regulations.gov. There were no comments received in 

response to the notice of filing.
    The current propylene oxide tolerances include some specific 
directions for use regarding fumigation frequency, duration and 
temperature. These directions are currently on affected labels. Because 
these directions are already on the label, they do not need to be 
duplicated as part of the tolerance. Furthermore, the propylene oxide 
Reregistration Eligibility Document (RED) of August 2006 found that 
these directions should be modified on the label to exactly match the 
conditions under which residue trials were conducted. Therefore, all 
directions in 40 CFR 180.491, paragraphs (a)(2) and (a)(4) are no 
longer needed and can be removed. Similarly, the use directions and 
other information in paragraphs (a)(1), and (a)(5) can also be removed. 
As noted in the petition and the RED, use of propylene oxide can result 
in residues of propylene oxide as well as the reaction product 
propylene chlorohydrin. Commodities that contain salts that are treated 
with propylene oxide can react with chloride ion to form the propylene 
chlorohydrin. Propylene oxide and propylene chlorohydrin are considered 
separately as residues of concern for risk assessment and tolerance 
assessment. Based on the differences in physical-chemical properties 
and toxicological effects, propylene oxide and propylene chlorohydrin 
were assessed separately, and, EPA is establishing separate tolerances 
for these chemicals within different paragraphs of tolerance regulation 
for propylene oxide.

III. Aggregate Risk Assessment and Determination of Safety

    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) of the 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 the 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....'' These provisions were added to the FFDCA by the Food 
Quality Protection Act (FQPA) of 1996.
    Consistent with FFDCA section 408(b)(2)(D), and the factors 
specified in 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 and to make a 
determination on aggregate exposure for the petitioned-for tolerance 
for residues of propylene oxide in or on fig; grape, raisin; and plum, 
prune, dried at 3.0; 1.0; and 2.0 ppm, respectively; and in addition, 
for residues of the reaction product propylene chlorohydrin at 3.0; 
4.0; and 2.0, ppm, respectively. EPA's assessment of exposures and 
risks associated with establishing the tolerance 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

[[Page 49648]]

subgroups of consumers, including infants and children. Specific 
information on the studies received and the nature of the adverse 
effects caused by propylene oxide and propylene chlorohydrin, as well 
as the no-observed-adverse-effect-level (NOAEL) and the lowest-
observed-adverse-effect-level (LOAEL) from the toxicity studies can be 
found at http://www.regulations.gov under the docket number for this 

rule.

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no 
appreciable risk, the toxicological level of concern (LOC) is derived 
from the highest dose at which no adverse effects are observed (the 
NOAEL) in the toxicology study identified as appropriate for use in 
risk assessment. However, if a NOAEL cannot be determined, the lowest 
dose at which adverse effects of concern are identified (the LOAEL) is 
sometimes used for risk assessment. Uncertainty/safety factors (UF) are 
used in conjunction with the LOC to take into account uncertainties 
inherent in the extrapolation from laboratory animal data to humans and 
in the variations in sensitivity among members of the human population 
as well as other unknowns. Safety is assessed for acute and chronic 
risks by comparing aggregate exposure to the pesticide to the acute 
population adjusted dose (aPAD) and chronic population adjusted dose 
(cPAD). The aPAD and cPAD are calculated by dividing the LOC by all 
applicable uncertainty/safety factors. Short-, intermediate, and long-
term risks are evaluated by comparing aggregate exposure to the LOC to 
ensure that the margin of exposure (MOE) called for by the product of 
all applicable uncertainty/safety factors is not exceeded.
    For non-threshold risks, the Agency assumes that any amount of 
exposure will lead to some degree of risk and estimates risk in terms 
of the probability of occurrence of additional adverse cases. 
Generally, cancer risks are considered non-threshold. 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/oppfead1/trac/science http://www.epa.gov/pesticides/.

ides/.

aggregate.pdf.
    A summary of the toxicological endpoints for propylene oxide and 
propylene chlorohydrin used for human risk assessment can be found at 
http://www.regulations.gov in the risk assessment document ``Propylene Oxide-

Revised HED Risk Assessment for Reregistration Eligibility Decision 
Document, July 31, 2006'' at Table 4.4.10 on page 49/95 in Docket ID 
EPA-HQ-OPP-2005-0157. This identical table can also be found in the 
Propylene oxide RED document at the following website address: http://www.epa.gov/oppsrrd1/REDs/propylene_oxide_red.pdf
.


C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to propylene oxide and propylene chlorohydrin, EPA considered 
exposure under the petitioned-for tolerances as well as all existing 
propylene oxide tolerances in (40 CFR 180.491). EPA assessed dietary 
exposures from propylene oxide and propylene chlorohydrin 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.
    In estimating acute dietary exposure for propylene oxide and 
propylene chlorohydrin, EPA used food consumption information from the 
USDA 1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by 
Individuals (CSFII). As to residue levels in food, EPA relied upon 
average field trial residue data and percent crop treated information 
for all commodities covered by existing tolerances.
    ii. Chronic exposure. In conducting the chronic dietary exposure 
assessment EPA used the food consumption data from the USDA 1994-1996 
and 1998 Nationwide (CSFII). As to residue levels in food, EPA relied 
upon average field trial residue data for propylene oxide, tolerance 
level residues for propylene chlorohydrin, and percent crop treated 
information for all commodities covered by existing propylene oxide 
tolerances.
    iii. Cancer. The cancer assessment for propylene oxide incorporated 
new residue and percent crop treated data for nutmeats and omitted guar 
(edible gums) as a fumigated commodity. No cancer exposure assessment 
is needed for propylene chlorohydrin because the cancer data which were 
negative for both rats and mice, showed no cancer risk to humans.
    iv. Anticipated residue and percent crop treated (PCT) information. 
Section 408(b)(2)(E) of the 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 pursuant 
to section 408(f)(1) require 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 section 408(f)(1) of 
FFDCA. Data will be required to be submitted no later than 5 years from 
the date of issuance of this tolerance.
    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:
    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 
such pesticide residue;
    b. The exposure estimate does not underestimate exposure for any 
significant subpopulation group; and
    c. Data are available on pesticide use and food consumption in a 
particular area, the exposure estimate does not understate exposure for 
the population in such area. In addition, the Agency must provide for 
periodic evaluation of any estimates used. To provide for the periodic 
evaluation of the estimate of PCT as required by section 408(b)(2)(F) 
of FFDCA, EPA may require registrants to submit data on PCT.
    The Agency used PCT information as follows:
    The percent crop treated values used were as follows: Herbs, 
spices, and bulb vegetables at 1%; tree nuts at 2%; cocoa bean at 1.3%; 
and 100% for the new proposed uses -- fig grape; raisin; and plum, 
prune, dried.
    The Agency believes that the three conditions listed above have 
been met. With respect to Condition 1, 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 2 and 3, 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

[[Page 49649]]

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 information on 
the regional consumption of food to which propylene oxide may be 
applied in a particular area.
    2. Dietary exposure from drinking water. For propylene oxide 
fumigations, residues of propylene oxide and propylene chlorohydrin 
from drinking water are expected to be negligible because
    i. Fumigations are either in closed chambers with emission 
reduction technology, or in temporary/intermittent outdoor field 
locations (tents, tarps, rail cars, etc.) at a use rate 53 times lower 
than that used in closed chambers, both of which result in minimal 
emissions, and
    ii. Due to atmospheric dilution and the physical-chemical 
characteristics of propylene oxide, negligible residues are expected to 
be able to enter soil and any nearby water. Therefore, water exposures 
were not included in the risk assessment.
    3. From non-dietary exposure. The term ``residential exposure'' is 
used in this document to refer to non-occupational, non-dietary 
exposure (e.g., for lawn and garden pest control, indoor pest control, 
termiticides, and flea and tick control on pets).
    Propylene oxide and propylene chlorohydrin are not registered for 
use on any residential sites. However, exposure could occur to people 
residing near fumigation facilities. Propylene oxide and propylene 
chlorohydrin emissions monitoring data necessary to quantitatively 
estimate exposures and risks from sterilization/fumigation facilities 
are unavailable. Therefore, a qualitative assessment was conducted 
comparing the risks associated with fugitive emissions from the use of 
a similar chemical, ethylene oxide, in similar commercial fumigation 
scenarios. With the use of required buffer zones at designated 
distances to be added to labels, the assessment found that propylene 
oxide and propylene chlorohydrin residential exposure risks are not 
expected to be of concern.
    4. Cumulative effects from substances with a common mechanism of 
toxicity. Section 408(b)(2)(D)(v) of the 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.''
    Unlike other pesticides for which EPA has followed a cumulative 
risk approach based on a common mechanism of toxicity, EPA has not made 
a common mechanism of toxicity finding as to propylene oxide or 
propylene chlorohydrin and any other substances and propylene oxide or 
propylene chlorohydrin do not appear to produce a toxic metabolite 
produced by other substances. For the purposes of this tolerance 
action, therefore, EPA has not assumed that propylene oxide or 
propylene chlorohydrin 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 of FFDCA provides that EPA shall apply 
an additional (``10X'') tenfold 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. In 
applying this provision, EPA either retains the default value of 10X 
when reliable data do not support the choice of a different factor, or, 
if reliable data are available, EPA uses a different additional FQPA 
safety factor value based on the use of traditional uncertainty/safety 
factors and/or special FQPA safety factors, as appropriate.
    2. Prenatal and postnatal sensitivity. For propylene oxide, there 
is no quantitative susceptibility between the rat fetuses and the dams 
from the rat developmental study. The study indicated a possible 
qualitative susceptibility since the skeletal variations (increased 
litter incidence for the accessory 7th cervical rib) were observed at 
the same dose which produced maternal toxic effects (ie. decreased body 
weight gain, food consumption and food efficiency). The effects in the 
rat fetuses are being treated as only possible evidence of qualitative 
sensitivity because it is questionable as to whether an accessory 7th 
cervical rib, which is a developmental variation, is properly 
characterized as a more severe effect than decreased body weight gain. 
Although further analysis, including consideration of historical 
control information on this effect, might resolve this question, in the 
absence of this analysis, EPA is taking the conservative position that 
this particular skeletal variation is possible evidence of qualitative 
sensitivity.
    Susceptibility in rabbits could not be adequately ascertained due 
to the absence of an acceptable rabbit developmental study. In the 2-
generation reproduction study, there is no evidence for quantitative or 
qualitative susceptibility in pups exposed to propylene oxide since no 
offspring effects were seen at doses which produced significant 
systemic toxicity in parents. The degree of concern for the possible 
qualitative susceptibility effects seen after in utero exposures in 
rats was low because the effects (ie. increased incidence of the 7th 
cervical rib) are:
    i. Skeletal variations and not malformations,
    ii. Were seen in the presence of maternal toxicity,
    iii. A clear NOAEL was identified, and
    iv. This endpoint is used for assessing potential acute dietary 
risk to the population of concern (Females 13-49). For propylene 
chlorohydrin, in the reproduction study, quantitative susceptibility 
effects were evident because decreased pup weights were observed at a 
dose which had no systemic toxicity in the dams. However, the degree of 
concern is low for the quantitative susceptibility seen in the 
reproduction study because a clear NOAEL was identified, and that dose 
and the endpoint of this study is used for assessing chronic dietary 
risk in conjunction with the retaining of a 10X database uncertainty 
factor.
    3. Conclusion. For both propylene oxide and propylene chlorohydrin, 
EPA has determined it is necessary to retain the additional 10X safety 
factor for the protection of infants and children due to the absence of 
a propylene oxide developmental toxicity study in rabbits, and a 
chronic study in non-rodents by the oral route; and for propylene 
chlorohydrin, due to the absence of a developmental toxicity study in 
rats and rabbits, a chronic toxicity study in nonrodents, and a chronic 
carcinogenicity study in rats and mice (because the doses used in the 
existing studies found in the literature are inadequate). Because no 
acute endpoint has been identified for propylene chlorohydrin, EPA has 
applied the additional 10X safety factor to the chronic endpoint in 
assessing acute risk for propylene chlorohydrin. This is a very 
conservative approach to assessing

[[Page 49650]]

acute risk because repeated exposure to a pesticide would typically 
result in lower NOAELs than an acute exposure. For propylene oxide, 
there is no evidence for quantitative or qualitative susceptibility in 
pups exposed to the chemical. For propylene chlorohydrin, the degree of 
concern is also low for the quantitative susceptibility seen in the 
reproduction study since the dose and the endpoint of this study is 
used for assessing chronic dietary risk in conjunction with the 
retaining of the 10X database uncertainty factor. No additional FQPA 
factor above 10X is required for either propylene oxide or propylene 
chlorohydrin. Propylene oxide is missing an adequate rabbit 
developmental study and a chronic study in a non-rodent species, but an 
existing developmental study in rabbits indicates effects occur at high 
doses and a chronic study in rodents is available, therefore a factor 
of 10X is sufficient. For propylene chlorohydrin, although there are 
data gaps, there are acceptable longer term studies including chronic 
studies in rats and mice and a reproduction study in rats. Given these 
chronic data, an additional safety factor of 10X should be sufficient 
for the protection of infants and children, as well as the general 
population and other major identifiable subgroups, from chronic 
exposure to propylene chlorohydrin. Further, use of the chronic 
endpoint and the additional 10X safety factor to assess acute risk is 
such a conservative approach to assessing acute risk that no further 
safety factor for this risk assessment. Other relevant factors here are 
that:
    i. There is no indication that propylene oxide or propylene 
chlorohydrin are neurotoxic chemicals and there is no need for 
developmental neurotoxicity studies or additional uncertainty factors 
to account for neurotoxicity; and
    ii. The exposure databases is unlikely to underestimate exposure 
because it is based on reliable data on anticipated residues and 
percent crop treated information.

E. Aggregate Risks and Determination of Safety

    Safety is assessed for acute and chronic risks by comparing 
aggregate exposure to the pesticide to the aPAD and cPAD. The aPAD and 
cPAD are calculated by dividing the LOC by all applicable uncertainty/
safety factors. For linear cancer risks, EPA calculates the probability 
of additional cancer cases given aggregate exposure. Short-, 
intermediate, and long-term risks are evaluated by comparing aggregate 
exposure to the LOC to ensure that the MOE called for by the product of 
all applicable uncertainty/safety factors is not exceeded. As discussed 
prior, because propylene oxide and propylene chlorohydrin residues 
which could enter water are expected to be negligible, water exposures 
were not included in the aggregate risk assessments.
    1. Acute risk. Using the exposure assumptions discussed in this 
unit for acute exposure, the acute dietary exposure from only food to 
propylene oxide will occupy 7% of the aPAD for the population group 
(females 13-49 years old) receiving the greatest exposure. Because no 
acute endpoint has been identified for propylene chlorohydrin, EPA has 
assessed acute risk for propylene chlorohydrin using the cPAD for 
propylene chlorohydrin. Using the exposure assumptions discussed in 
this unit for acute exposure, the acute dietary exposure from only food 
to propylene chlorohydrin will occupy 90% of the cPAD for the 
population group receiving the greatest exposure (infants less than one 
year old).
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that exposure to propylene 
oxide from only food will utilize 14% of the cPAD for the population 
group (children 3-5 years). Using the exposure assumptions described in 
this unit for chronic exposure, EPA has concluded that exposure to 
propylene chlorohydrin from only food will utilize 29% of the cPAD for 
the population group (children 1-2 years). There are no residential 
uses for propylene oxide or propylene chlorohydrin, but residential 
bystanders may be exposed to air emissions from fumigation facilities 
or structures. However, dietary and bystander exposure for either 
propylene oxide or propylene chlorohydrin cannot be combined for this 
assessment because the endpoints selected for these exposures are not 
based on a common effect. Therefore, risk from dietary and inhalation 
routes were not aggregated.
    3. Short-term risk. Short-term aggregate exposure takes into 
account residential exposure plus chronic exposure to food and water 
(considered to be a background exposure level).
    Though residential exposure could occur with the use of propylene 
oxide, the potential short-term exposures to propylene oxide and 
propylene chlorohydrin were not aggregated with chronic dietary food 
and water exposures for the same because the toxic effects are 
different.
    4. Intermediate-term risk. Intermediate-term aggregate exposure 
takes into account residential exposure plus chronic exposure to food 
and water (considered to be a background exposure level).
    Though residential exposure could occur with the use of propylene 
oxide, the potential intermediate-term exposures propylene oxide and 
propylene chlorohydrin were not aggregated with chronic dietary food 
and water exposures for the same because the toxic effects are 
different.
    5. Aggregate cancer risk for U.S. population. The cancer dietary 
risk estimates for propylene oxide are below EPA's level of concern; 
the cancer dietary excess lifetime risk estimate for the U.S. general 
population is 4x10-7. EPA considers risks in the range of 1 
x 10-6 (such as the cancer risk for propylene oxide) to be 
negligible and thus pose a reasonable certainty of no harm. There is no 
cancer risk for propylene chlorohydrin as evidenced by the cancer data 
which were negative for both rats and mice.
    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 propylene oxide and propylene chlorohydrin residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology is available to enforce the 
tolerance expression. An acceptable method was submitted (ABC.METHOD 
46306-PPO/Hydrins Rev 1.0; MRID 45301902) which is able to quantify 
propylene oxide and propylene chlorohydrin residues in various 
commodities using headspace gas chromatography with flame ionization 
detection. The method may be requested from: Chief, Analytical 
Chemistry Branch, Environmental Science Center, 701 Mapes Rd., Ft. 
Meade, MD 20755-5350; telephone number: (410) 305-2905; e-mail address: 
residuemethods@epa.gov.


B. International Residue Limits

    There are no Codex Maximum Residue Levels (MRLs) for residues of 
propylene oxide and propylene chlorohydrin in any commodity. No 
Canadian or Mexican MRLs have been established.

V. Conclusion

    Therefore, tolerances are established for residues of propylene 
oxide when used as a post harvest fumigant, in or on fig; grape, 
raisin; and plum, prune, dried, at 3.0; 1.0; and 2.0; respectively

[[Page 49651]]

ppm, and separate tolerances are established for the reaction product, 
propylene chlorohydrin, in or on fig; grape, raisin; and plum, prune, 
dried, at 3.0, 4.0, and 2.0 ppm, respectively. The use directions 
currently listed in 40 CFR 180.491 paragraphs (a)(1), (a)(2), (a)(4) 
and (a)(5) are also being removed.

VI. Statutory and Executive Order Reviews

    This final rule establishes a tolerance 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 rule has been 
exempted from review under Executive Order 12866, this rule is not 
subject to Executive Order 13211, 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 6, 
2000) do not apply to this rule. In addition, This 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 17, 2007.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

0
Therefore, 40 CFR chapter I is amended as follows:

PART 180--AMENDED

0
1. The authority citation for part 180 continues to read as follows:

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

0
2. Section 180.491 is amended by revising paragraph (a) to read as 
follows:


Sec.  180.491  Propylene oxide; tolerances for residues.

    (a) General. (1) Tolerances are established for residues of 
propylene oxide when used as a postharvest fumigant in or on the 
following food commodities:

------------------------------------------------------------------------
                                                              Parts per
                         Commodity                             million
------------------------------------------------------------------------
Cocoa bean, bean...........................................          300
Fig........................................................          3.0
Grape, raisin..............................................          1.0
Gum, edible................................................          300
Nutmeat, processed, except peanuts.........................          300
Plum, prune, dried.........................................          2.0
Spices, processed..........................................          300
------------------------------------------------------------------------

    (2) Tolerances are established for the reaction product, propylene 
chlorohydrin, from use of propylene oxide as a postharverst fumigant, 
in or on the following food commodities:

------------------------------------------------------------------------
                                                              Parts per
                         Commodity                             million
------------------------------------------------------------------------
Fig........................................................          3.0
Grape, raisin..............................................          4.0
Plum, prune, dried.........................................          2.0
------------------------------------------------------------------------

* * * * *

[FR Doc. E7-17010 Filed 8-28-07; 8:45 am]

BILLING CODE 6560-50-S
