
[Federal Register: July 2, 2008 (Volume 73, Number 128)]
[Rules and Regulations]               
[Page 37852-37858]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr02jy08-37]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2006-1024; FRL-8368-1]

 
Residues of Quaternany Ammonium Compounds, Didecyl Dimethyl 
Ammonium Carbonate and Didecyl Dimethyl Ammonium Bicarbonate; Exemption 
from the Requirement of a Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes an exemption from the requirement 
of a tolerance for residues of the quaternany ammonium compounds, 
didecyl dimethyl ammonium carbonate and didecyl dimethyl ammonium 
bicarbonate (hereinafter cited jointly as DDACB), on food-contact 
surfaces when applied/used in public eating places, dairy processing 
equipment, and/or food processing equipment and utensils. Lonza, Inc., 
submitted a petition to EPA under the Federal Food, Drug, and Cosmetic 
Act (FFDCA), as amended by the Food Quality Protection Act of 1996 
(FQPA), requesting to establish concentration limits of DDACB in end-
use products eligible for the exemption from the requirement of a 
tolerance. As amended, the regulation will exempt solutions from the 
requirement of tolerance residues resulting from contact with surfaces 
treated with solutions where the end-use concentration of DDACB does 
not exceed 240 parts per million (ppm).

DATES: This regulation is effective July 2, 2008. Objections and 
requests for hearings must be received on or before September 2, 2008, 
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-2006-1024. 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 website 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 either in the electronic docket at http://
www.regulations.gov, or, if only available in hard copy, at the Office 
of Pesticide Programs (OPP) Regulatory Public Docket in Rm. S-4400, One 
Potomac Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The 
hours of operation of this Docket Facility are 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: Velma Noble, Antimicrobials Division 
(7510P), Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001; telephone

[[Page 37853]]

number: (703) 308-6233; e-mail address: noble.velma@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 dairy 
cattle milk producer, food manufacturer, or beverage manufacturer. 
Potentially affected entities may include, but are not limited to:
      Dairy Cattle Milk Production (NAICS code 11212).
      Food manufacturing (NAICS code 311).
      Beverage Manufacturing (NAICS code 3121).
     This listing is not intended to be exhaustive, but rather provides 
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 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 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 FFDCA, as amended by FQPA, any person may 
file an objection to any aspect of this regulation and may also request 
a hearing on those objections. The EPA procedural regulations which 
govern the submission of objections and requests for hearings appear in 
40 CFR part 178. 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-2006-1024 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 on or before September 2, 2008.
     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 your copies, identified by docket ID 
number EPA-HQ-OPP-2006-1024, 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 Exemption

     In the Federal Register of November 28, 2007 (72 FR 67300) (FRL-
8141-2), 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 tolerance 
petition (PP 6F7131) by Lonza, Inc., 90 Boroline Rd., Allendale, NJ 
07401. The petition requested that 40 CFR 180.190(a) be amended by 
establishing concentration limits for DDACB in end-use solutions 
eligible for tolerance exemption. That notice referenced a summary of 
the petition prepared by Lonza, Inc., 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.

III. Aggregate Risk Assessment and Determination of Safety

     Section 408(c)(2)(A)(i) of FFDCA allows EPA to establish an 
exemption from the requirement for 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(c)(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. Pursuant to section 408(c)(2)(B) of FFDCA, in 
establishing or maintaining in effect an exemption from the requirement 
of a tolerance, EPA must take into account the factors set forth in 
section 408(b)(2)(C) of FFDCA, which 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(c)(2)(A) of FFDCA, and the factors 
specified in section 408(c)(2)(B) 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 the petitioned-for 
exemption from the requirement for a tolerance for residues of DDACB on 
food-contact surfaces in public eating places, dairy processing 
equipment, and food processing equipment and utensils. EPA's assessment 
of exposures and risks associated with establishing the exemption from 
the requirement for a 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 subgroups of consumers, including infants and 
children. Specific information on the studies received and the nature 
of the adverse effects caused by DDACB as well as the no-observed-
adverse-effect-level (NOAEL) and the lowest-observed-adverse-effect-
level (LOAEL) from the toxicity studies are discussed in this unit.
     DDACB is a part of the aliphatic alkyl quaternaries chemical case 
which is comprised of six compounds that are structurally similar 
quaternary ammonium compounds (quats). This group of chemicals are 
characterized by having a positively charged nitrogen covalently bonded 
to two alkyl group substituents (at least one C8 or longer)

[[Page 37854]]

and two methyl substituents. In finished form, these quats are salts 
with positively charged nitrogen (cation) balanced by a negatively 
charged molecule (anion). The anion for the quats in this group are 
chlorine, carbonate, bicarbonate, or bromine.
     In 1988, EPA issued PR Notice 88-2 outlining ``Clustering of 
Quaternary Ammonium Compounds.'' In that PR Notice, quats were 
clustered into 4 groups as follows:
     Group I: The alkyl or hydroxyalkyl (straight chain) substituted 
quats; otherwise referred to as the aliphatic alkyl quaternaries.
     Group II: The non-halogenated benzyl substituted quats (including 
alkyl benzyl, dodecyhlbenzyl, hydroxybenzyl, hydroxyethylbenzyl, and 
naphylmethyl).
     Group III: The di- and tri-chlorobenzyl substituted quats.
     Group IV: Quats with unusual substitutes (charged heterocyclic 
compounds).
     In all types of aliphatic alkyl ammonium chloride quaternaries, it 
is the positive entity (quaternized nitrogen containing the aliphatic 
alkyl and/or aromatic alkyl groups) that is of relevance from 
toxicology and exposure perspectives. The negative part of the 
aliphatic alkyl ammonium chloride quaternaries (counter ion) is 
relatively non-toxic entities (bicarbonate, carbonate, chloride). 
Aliphatic alkyl ammonium chloride quaternaries were originally 
formulated with chloride as the negative or the counter ion. However, 
one negative ion in the aliphatic alkyl ammonium chloride quaternaries 
can be replaced with another without disrupting the structural 
integrity of the chemical (i.e., quaternized nitrogen) and thereby 
without having a significant effect on toxicity. Accordingly, the 
toxicological profiles of the aliphatic alkyl ammonium chloride 
quaternaries are very similar and a toxicological assessment of any of 
the aliphatic alkyl ammonium chloride quaternaries is representative of 
the group. Didecyl dimethyl ammonium chloride (DDAC), was chosen as the 
representative chemical for aliphatic alkyl ammonium chloride 
quaternaries because it was registered first. On this basis, the 
toxicology database for DDAC is accepted as representative of the 
hazard for this class of quaternary ammonium compounds.
     The aliphatic alkyl ammonium chloride quaternaries are corrosive, 
highly irritating to the eye and skin, with moderate acute toxicity by 
oral, dermal, and inhalation routes of exposure. These chemicals are 
classified as ``not likely'' to be a human carcinogen based on negative 
carcinogenicity studies in rats and mice feeding studies using doses 
above limit dose. There is no evidence of these chemicals being 
associated with increased susceptibility to developmental toxicity or 
reproductive toxicity based on two developmental toxicity studies and a 
2-generation reproductive study. Lastly, they are negative for 
mutagenicity and neurotoxicity.
     Specific information on the studies received and the nature of the 
toxic effects caused by aliphatic alkyl quaternaries can be found at 
http://www.regulations.gov. Docket ID Number EPA-HQ-OPP-2006-0338, 
Didecyl Dimethyl Ammonium Chloride (DDAC)--Report of Antimicrobials 
Division Toxicity Endpoint Committee (ADTC) and the Hazard 
Identification Assessment Review Committee (HIARC).

B. Toxicological Endpoints

     For hazards that have a threshold below which there is no 
appreciable risk, a toxicological point of departure (POD) is 
identified as the basis for derivation of reference values for risk 
assessment. The POD may be defined as 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) or a Benchmark Dose (BMD) approach 
is sometimes used for risk assessment. Uncertainty/safety factors (UFs) 
are used in conjunction with the POD 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. The Level of Concern (LOC) is a reference 
value expressed as either a reference dose/population adjusted dose 
(RfD/PAD) or margin of exposure (MOE). Safety is assessed for acute and 
chronic dietary risks by comparing aggregate food and water 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 POD by all applicable UFs. Aggregate short-, intermediate-
, and chronic-term risks are evaluated by comparing food, water, and 
residential exposure to the POD to ensure that the MOE called for by 
the product of all applicable UFs 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 a cancer occurrence greater than that expected in 
a lifetime. 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/pesticides/factsheets/riskassess.htm.
     The Agency's LOC for aliphatic alkyl ammonium chloride 
quaternaries' inhalation and oral exposures is 100 (i.e., a MOE less 
than 100 exceeds the Agency's level of concern). The LOC is based on an 
UF of 10x for interspecies extrapolation and 10x UF for intraspecies 
extrapolation. For dermal exposures, irritation as the effect was 
selected for the short-term endpoint and a reduced MOE was used to 
characterize the risk. The use of irritation as a toxic endpoint for 
assessment of dermal risk is appropriate in this case, as dermal 
exposure that results in primarily an irritation response is considered 
a self-limiting type of exposure that is not expected to last for any 
length of time, and variability in the response is not expected to be 
as great as systemic toxic responses. For aliphatic alkyl quaternaries, 
the MOE for short-term dermal risk is reduced to a total factor of 10x 
(3x for interspecies extrapolation, 3x for intraspecies variation).
     A summary of the toxicological endpoints for aliphatic alkyl 
quaternaries used for human risk assessment is shown in Table 1 of this 
unit. Specific information on the studies received such as the NOAEL 
and the LOAEL from the toxicity studies caused by aliphatic alkyl 
quaternaries can be found at http://www.regulations.gov. Docket ID 
Number EPA-HQ-OPP-2006-0338, Didecyl Dimethyl Ammonium Chloride 
(DDBAC)--Report of Antimicrobials Division Toxicity Endpoint Committee 
(ADTC) and the Hazard Identification Assessment Review Committee 
(HIARC).

[[Page 37855]]



 Table 1. --Summary of Toxicological Doses and Endpoints for Aliphatic Alkyl Ammonium Chloride Quaternaries for
                                          Use in Human Risk Assessment
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                                        Point of Departure and
          Exposure/Scenario               Uncertainty/Safety     RfD, PAD, LOC for Risk  Study and Toxicological
                                               Factors                 Assessment                Effects
----------------------------------------------------------------------------------------------------------------
Acute dietary                          NOAEL = 10 milligrams/   Acute RfD = 0.1 mg/kg/   Prenatal Developmental
 (Females 13-50 years of age)........   kilograms/day (mg/kg/    day                      Toxicity--Rat
                                        day) UFA = 10x          aPAD = 0.1 mg/kg/day...  (MRID 41886701)
                                       UFH = 10 x.............                           LOAEL = 20 mg/kg/day
                                       FQPA SF = 1x...........                            based on increased
                                                                                          incidence of skeletal
                                                                                          variations.
----------------------------------------------------------------------------------------------------------------
Chronic dietary                        NOAEL= 10 mg/kg/day UFA  Chronic RfD =0.1 mg/kg/  Chronic Toxicity--Dog
(All populations)....................   = 10x                    day                     (MRID 41970401)
                                       UFH = 10 x.............  cPAD = 0.1 mg/kg/day...  LOAEL = 20 mg/kg/day
                                       FQPA SF = 1x...........                            based on increased
                                                                                          incidence of clinical
                                                                                          signs in males and
                                                                                          females and decreased
                                                                                          total cholesterol
                                                                                          levels in females.
----------------------------------------------------------------------------------------------------------------
Incidental oral short-term             NOAEL= 10 mg/kg/day UFA  LOC for MOE = 100        Prenatal Developmental
(1 to 30 days).......................   = 10x                                             Toxicity--Rat
                                       UFH = 10 x.............                           (MRID 41886701)
                                       FQPA SF = 1x...........                           LOAEL = 20 mg/kg/day
                                                                                          based on increased
                                                                                          incidence of skeletal
                                                                                          variations.
----------------------------------------------------------------------------------------------------------------
Incidental oral intermediate-term      NOAEL= 10 mg/kg/day      LOC for MOE = 100        Chronic Toxicity--Dog
(1 to 6 months)......................   UFA= 10x.                                        (MRID 41970401)
                                       UFH= 10x...............                           LOAEL = 20 mg/kg/day
                                       FQPA SF =1x............                            based on increased
                                                                                          incidence of clinical
                                                                                          signs in males and
                                                                                          females and decreased
                                                                                          total cholesterol
                                                                                          levels in females
----------------------------------------------------------------------------------------------------------------
Dermal short-term                        No endpoint identified. No dermal or systemic effects identified in the
(formulated product 0.13% a.i.)......     21-day dermal toxicity study (MRID 45656601) up to and including the
                                                             limit dose of 1,000 mg/kg/day.
----------------------------------------------------------------------------------------------------------------
Dermal short-term                      Dermal study NOAEL= 2    LOC for MOE = 10         90-Day Dermal Toxicity--
(1 to 6 months)......................   mg/kg/day ( (8                                    Rat
                                        micrograms (ug)/                                 (MRID 41305901)
                                        centimeters                                      LOAEL = 6 mg/kg/day
                                        (cm)\2\)\a\ %when                                 based on increased
                                        appropriate)                                      clinical and gross
                                       UFA = 3 x..............                            findings (erythema,
                                       UFH = 3x...............                            edema, exfoliation,
                                       FQPA SF = 1x...........                            excoriation, and
                                                                                          ulceration.
----------------------------------------------------------------------------------------------------------------
Dermal intermediate- and Long-term...                            No endpoint identified.
----------------------------------------------------------------------------------------------------------------
Inhalation short-term                   Oral study NOAEL\b\=    LOC for MOE = 100        Prenatal Developmental
(1 to 30 days).......................   10 mg/kg/day                                      Toxicity
                                        (inhalation absorption                           (MRID 41886701)
                                        rate = 100%)                                     LOAEL = 20 mg/kg/day
                                       UFA = 10 x.............                            based on increased
                                       UFH = 10 x.............                            incidence of skeletal
                                       FQPA SF = 1x...........                            variations.
----------------------------------------------------------------------------------------------------------------
Inhalation                             Oral) study NOAEL\b\ =   LOC for MOE = 100        Chronic Toxicity Study--
(1 to 6 months)......................   10 mg/kg/day                                      Dog
                                        (inhalation absorption                           (MRID 41970401)
                                        rate = 100%)                                     LOAEL = 20 mg/kg/day
                                       UFA = 10x..............                            based on increased
                                       UFH = 10x..............                            incidence of clinical
                                       FQPA SF = 1x...........                            signs males and
                                                                                          females and decreased
                                                                                          total cholesterol
                                                                                          levels in females.
----------------------------------------------------------------------------------------------------------------
UFA = extrapolation from animal to human (interspecies). UFH = potential variation in sensitivity among members
  of the human population (intraspecies). UFL = use of a LOAEL to extrapolate a NOAEL. UFS = use of a short-term
  study for long-term risk assessment. UFDB = to account for the absence of data or other data deficiency. FQPA
  SF = FQPA Safety Factor. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE =
  margin of exposure. LOC = level of concern.
\a\ Short-term dermal endpoint = (2 mg/kg rat x 0.2 kg rat x 1,000 ug/mg)/50 cm\2\ area of rat dosed = 8 ug/
  cm\2\.
\b\ An additional UF of 10x is used for route extrapolation from an oral endpoint to determine, if a
  confirmatory study is warranted.

C. Exposure Assessment

     1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to DDACB, EPA considered exposure under the petitioned-for 
exemption as well as all existing aliphatic alkyl quaternaries 
exemptions or tolerances in (40 CFR 180.940(a)). EPA assessed dietary 
exposures from DDACB in food as follows:
     Aliphatic alkyl quaternaries are to be used as a sanitizer on 
appliances, beverage bottling, counter tops, food packaging, 
refrigerators, tables, and utensils. The use of these actives in 
antimicrobial products for use on food

[[Page 37856]]

or feed-contact surfaces, agricultural commodities, and application to 
food-grade eggs may result in pesticide residues in human food. 
Residues from treated surfaces, such as appliances, countertops, 
equipment, and utensils can migrate to food coming into contact with 
the treated and rinsed surfaces and can be ingested by humans.
     The Agency assessed acute and chronic dietary exposures from the 
use of DDACB as a disinfectant and food-contact sanitizer on utensils, 
countertops, and in food/beverage processing facilities. The assessment 
calculated the Daily Dietary Dose (DDD) and the Estimated Daily Intake 
(EDI) using modified Food and Drug Administration (FDA) methodologies 
for utensils and Indirect Dietary Residential Exposure Model software 
(IDREAM) for countertops. IDREAM incorporates consumption data from 
United States Department of Agriculture (USDA) Continuing Survey of 
Food Intakes by Individuals (CSFII) for 1994-1996 and 1998. The USDA 
CSFII 1994-1996 and 1998 data are based on the reported consumption of 
more than 20,000 individuals over two non-consecutive survey days.
     The EDI calculations presented in this assessment for treated 
indirect dietary exposures resulting from sanitizing utensils assumed 
that food would contact 4,000 cm\2\ (which represents contact with 
treated china, glass, and silverware used by an individual who 
regularly eats three meals per day at an institutional or public 
facility) and that the residual solution remaining on the surface or 
pesticide migration fraction is 1 mg/cm\2\ of treated area. The body 
weights used for this assessment were 70 kg for an adult male, 60 kg 
for an adult woman, and 10 kg for an infant. Based on data provided in 
a new residue study, Transferability Equivalence among Quats and 
Measured Food Surrogate Transfer Efficiency (MRID 46870703), a 
conservative transfer rate of 43% was used to demonstrate the amount of 
residues on the surface that will be transferred to food and 
subsequently ingested. The maximum application rate for DDACB on 
utensils is 0.0020 lbs active ingredient (a.i) per gallon of treatment 
solution.
     There are two levels of refinement for assessing dietary exposure 
to antimicrobial products used on countertops. The three dimensional 
approach, Tier 2, was utilized for this assessment. This conservative 
approach uses food consumption and preparation patterns as well as data 
and assumptions that are not chemical specific. Food ingredients are 
separated into nine categories based on food preparation, food physical 
properties, and potential, or likelihood of contact with treated 
countertops. The nine food categories are liquids, fruit, bread, 
cheese, vegetable, meat, purees (e.g., oatmeal, pudding), pieces (foods 
normally consumed in small pieces), and powders (foods normally used in 
powder/granular forms). Assumed countertop residues are converted to 
estimated residues contacting the countertops using a translation 
factor for each food category, and default residue transfer efficiency 
for a representative food. Therefore, IDREAM combines the estimated 
countertop residues for surface treatment products, CSFII consumption 
data, food-specific conversion factors that relate the surface area 
contacting a countertop with corresponding weight of the food item, and 
the transfer efficiency of residues from countertops to food. 
Conservative assumptions for these analyses include: All disinfectants 
registered to disinfect kitchen countertops are included; all foods are 
prepared on those countertops; all prepared foods will come in contact 
with treated countertops at the maximum application rate and transfer 
residues do not diminish over time (i.e., residue reduction will not 
occur from cooking or preparation processes); there is a 100% 
likelihood of contact to account for both commercial and residential 
scenarios: All commercial and households use the same active 
ingredients; all foods are prepared and consumed.
     When assessing the food bottling/packaging use, EPA assumed a 100% 
transfer rate because the food is potentially in contact with the 
treated surfaces for very long periods of time. The maximum application 
rate for DDACB for bottling/packing of food is 0.0020 lbs a.i. per 
gallon of treatment solution. EDI values were calculated using an 
approach similar to that used for treated food utensils. Exposure was 
assumed to occur through the ingestion of three food products that 
might be packaged with treated material: Beverages (alcoholic and non-
alcoholic), egg products, and milk. A calorie intake modification 
factor of 0.64 was applied to the EDI for a child to account for the 
differences between intake values among children and adults. The 
calculated percent of an aPAD and a cPAD do not exceed 100% and 
therefore are not of a concern.
     2. Dietary exposure from drinking water. DDACB outdoor uses are as 
an algaecide in wood preservative treatment and a slimicide in 
secondary oil field uses. The oil field uses are considered to be 
contained. The other uses are not expected to significantly contaminate 
drinking water sources. Therefore, the DDACB contributions for drinking 
water exposure are considered to be negligible and are not quantified.
     3. From non-dietary exposure. The term ``residential exposure'' is 
used in this document to refer to non-occupational, non-dietary 
exposure (e.g., textiles (clothing and diapers), carpets, swimming 
pools, and hard surface disinfection on walls, floors, tables).
     DDACB is currently registered for the following residential non-
dietary sites: Homes and day-care nurseries. EPA assessed residential 
exposure using the following assumptions:
     Residential exposure may occur during the application as well as 
post application of DDACB to indoor hard surfaces (e.g., mopping, 
trigger pump sprays, wiping). The residential handler scenarios were 
assessed to determine dermal and inhalation exposures. Residential post 
application scenarios such as children exposure to treated toys and 
floors were also assessed to determine dermal and incidental oral 
exposures. Surrogate dermal, inhalation, and incidental oral unit 
exposure values were estimated using Pesticide Handler Exposure 
Database (PHED) data and the Chemical Manufactures Association 
Antimicrobial Exposure Assessment Study (EPA, 1999). Note that for this 
assessment, EPA assumed that residential users complete all elements of 
an application (mix/load/apply) without the use of personal protective 
equipment.
     The duration for most residential exposures is believed to be best 
represented by the short-term duration (1 to 30 days). The short-term 
duration was chosen for this assessment because the residential handler 
and post-application scenarios are assumed to be performed on an 
episodic, not daily basis.
     Specific information on the residential exposure assessment for 
DDACB can be found at http://www.regulations.gov. Docket ID Number EPA-
HQ-OPP-2006-1024, Review of Petition to Amend 40 CFR 180.940 to add 
Didecyl Dimethyl Ammonium Carbonate/Bicarbonate.
     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

[[Page 37857]]

substances that have a common mechanism of toxicity.''
     EPA's risk assessment for the Group I Cluster is based on an 
assessment of the cumulative exposure to all aliphatic alkyl quaternary 
compounds. The individual exposure scenarios in the DDAC assessments 
(as well as the aggregate assessment in the Aliphatic Alkyl Quaternary 
(DDAC) Reregistration Eligibility Decision (RED)) were developed by 
assuming that a DDAC compound was used on 100% of the surfaces 
authorized on the label that could result in human exposure and summing 
the percent active ingredients on the labels for all of the aliphatic 
alkyl quaternary compounds when used in combination. Thus, because the 
risk assessment for DDAC accounts for exposures to all of the aliphatic 
alkyl quaternary compounds, there is no need for a separate cumulative 
risk assessment for those compounds. The Agency has not identified any 
other substances as sharing a common mode of toxicity with DDAC.

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 SF. 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 SF value based 
on the use of traditional UFs and/or FQPA SFs, as appropriate.
     2. Prenatal and postnatal sensitivity. Given the data on the 
aliphatic alkyl ammonium chloride quaternaries, there is no evidence 
that DDACB result in increased susceptibility in in utero rats or 
rabbits in the prenatal developmental studies or in young rats in the 
2-generation reproduction study.
     3. Conclusion. EPA has determined that reliable data show that it 
would be safe for infants and children to reduce the FQPA SF to 1x. 
That decision is based on the following findings:
     i. The toxicity database for aliphatic alkyl ammonium chloride 
quaternaries is complete.
     ii. There is no indication that aliphatic alkyl ammonium chloride 
quaternaries are a neurotoxic chemical and there is no need for a 
developmental neurotoxicity study or additional UFs to account for 
neurotoxicity.
     iii. There is no evidence that aliphatic alkyl ammonium chloride 
quaternaries result in increased susceptibility in in utero rats or 
rabbits in the prenatal developmental studies or in young rats in the 
2-generation reproduction study.
     iv. There are no residual uncertainties identified in the exposure 
databases. Although EPA may, in the future, refine exposure estimates 
for aliphatic alkyl ammonium chloride quaternaries based on more 
sophisticated modeling techniques, the current exposure assessment is 
based on a combination of conservative assumptions that is likely to 
overstate exposure from food to aliphatic alkyl ammonium chloride 
quaternaries.

E. Aggregate Risks and Determination of Safety

     1. Dietary risks from food and feed uses. EPA compares the 
estimated dietary exposures to an aPAD and a cPAD, 0.1 mg/kg/day, which 
are the same value for DDACB. Generally, a dietary exposure estimate 
that is less than 100% of the aPAD or the cPAD does not exceed the 
Agency's LOC.
     The antimicrobial indirect food use acute and chronic risk 
estimates from exposure to treated utensils and countertops are below 
the Agency's LOC. For adult males, the acute and chronic dietary 
exposure risk estimates are 5.9% for utensils and 1. 92% for 
countertops. The aPAD and cPAD for adult females of child bearing age 
(13-49), the highly exposed group, is 6.9% for utensils and 1. 79% for 
countertops. For children ages 1-2, the most highly exposed population 
subgroup, the acute and chronic dietary risk estimates are 41. 3% for 
utensils and 6.21% for countertops. Therefore, dietary exposure 
estimates are below the Agency's LOC for all population subgroups. The 
antimicrobial indirect food use chronic risk estimates from exposure to 
treated food packaging and beverage bottles are below the Agency's LOC. 
The percent cPAD values exceeded 100% and are not of concern.
     Specific information on the dietary exposure assessment for DDACB 
can be found at http://www.regulations.gov. Docket ID Number EPA-HQ-
2006-1024, Review of Petition to Amend 40 CFR 180.940 to add Didecyl 
Dimethyl Ammonium Carbonate/Bicarbonate.
     2. Non-occupational risk. Aggregate exposure takes into account 
residential exposure plus chronic exposure to food and water 
(considered to be a background exposure level). Using the exposure 
assumptions described in this unit for other non-occupational 
exposures, EPA has concluded that food, water, and residential 
exposures aggregated result in aggregate MOEs greater than or equal to 
100 for the inhalation route of exposure and 10 for dermal exposure; 
therefore, are not of concern.
     Based on the toxicological and exposure data discussed in this 
preamble, EPA concludes that DDACB will not pose a risk under 
reasonably foreseeable circumstances. Accordingly, EPA finds that there 
is a reasonable certainty that no harm will result to the general 
population, or to infants and children from aggregate exposure to DDACB 
residues.

IV. Other Considerations

     An analytical method for food is not needed. Food-contact 
sanitizers are typically regulated by the State health departments to 
ensure that the food industry is using products in compliance with the 
regulations in 40 CFR 180.940. The end-use solution that is applied to 
the food-contact surface is analyzed not food items that may come into 
contact with treated surface. An analytical method is available to 
analyze the use dilution that is applied to food-contact surfaces. A 
titration method is used to determine the total amount of quaternary 
compound. If the use solution is a mixture of ADBAC and DDACB, then 
high pressure liquid chromatogram with ultraviolet visible (HPLC-UV) is 
used to determine the amount of ADBAC. The amount of DDACB is 
determined by calculating the difference between the total amount of 
quaternary compounds and ADBAC.

V. Conclusion

     Therefore, an exemption is established for residues of DDACB, 
regulated chemical, on food-contact surfaces in public eating 
establishments, on dairy processing equipment, and food processing 
equipment and utensils.

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 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,

[[Page 37858]]

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 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, Aliphatic alkyl quaternaries, Food-contact 
sanitizers, Pesticides and pests, Quaternary ammonium compounds, 
Reporting and recordkeeping requirements.


    Dated: June 10, 2008.
Frank Sanders,
Director, Antimicrobials 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 180.940 is amended by alphabetically adding an entry to the 
table in paragraph (a) to read as follows:


Sec.  180.940  Tolerance exemptions for active and inert ingredients 
for use in antimicrobial formulations (Food-contact surface sanitizing 
solutions).

* * * * *
    (a) * * *

------------------------------------------------------------------------
       Pesticide Chemical            CAS Reg. No.           Limits
------------------------------------------------------------------------

                              * * * * * * *
Quaternary ammonium compounds,    148788-55-0/148812- When ready for
 didecyl dimethyl ammonium         654-1               use, the end-use
 carbonate/didecyl dimethyl                            concentration of
 ammonium bicarbonate                                  these specific
                                                       ammonium
                                                       compounds is not
                                                       to exceed 240 ppm
                                                       of active
                                                       quaternary
                                                       ammonium
                                                       compound.

                              * * * * * * *
------------------------------------------------------------------------

* * * * *
[FR Doc. E8-14880 Filed 7-1-08; 8:45 am]

BILLING CODE 6560-50-S
