[Federal Register Volume 76, Number 22 (Wednesday, February 2, 2011)]
[Rules and Regulations]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-2265]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
Isobutane; Exemption From the Requirement of a Tolerance
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
SUMMARY: This regulation establishes an exemption from the requirement
of a tolerance for residues of isobutane (CAS Reg. No. 75-28-5) when
used as an inert ingredient (propellant) in pesticide formulations
applied to growing crops and raw agricultural commodities after
harvest, and when used as an inert ingredient (propellant) in pesticide
formulations applied to animals (used for food). Landis International,
on behalf of Whitmire Micro-Gen, submitted a petition to EPA under the
Federal Food, Drug, and Cosmetic Act (FFDCA), requesting establishment
of an exemption from the requirement of a tolerance. This regulation
eliminates the need to establish a maximum permissible level for
residues of isobutane.
DATES: This regulation is effective February 2, 2011. Objections and
requests for hearings must be received on or before April 4, 2011 and
must be filed in accordance with the instructions provided in 40 CFR
part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).
ADDRESSES: EPA has established a docket for this action under docket
identification (ID) number EPA-HQ-OPP-2009-0676. All documents in the
docket are listed in the docket index available at http://www.regulations.gov. Although listed in the index, some information is
not publicly available, e.g., Confidential Business Information (CBI)
or other information whose disclosure is restricted by statute. Certain
other material, such as copyrighted material, is not placed on the
Internet and will be publicly available only in hard copy form.
Publicly available docket materials are available in the electronic
docket at http://www.regulations.gov, or, if only available in hard
copy, at the OPP Regulatory Public Docket in Rm. S-4400, One Potomac
Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The Docket
Facility is open from 8:30 a.m. to 4 p.m., Monday through Friday,
excluding legal holidays. The Docket Facility telephone number is (703)
FOR FURTHER INFORMATION CONTACT: Elizabeth Fertich, Registration
Division (7505P), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001; telephone number: (703) 347-8560; e-mail address:
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:
Crop production (NAICS code 111).
Animal production (NAICS code 112).
Food manufacturing (NAICS code 311).
Pesticide manufacturing (NAICS code 32532).
This listing is not intended to be exhaustive, but rather 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
B. How can I get electronic access to other related information?
You may access a frequently updated electronic version of 40 CFR
part 180 through the Government Printing Office's e-CFR site at http://www.gpoaccess.gov/ecfr. To access the harmonized test guidelines
referenced in this document electronically, please go to http://www.epa.gov/ocspp and select ``Test Methods and Guidelines.''
C. How can I file an objection or hearing request?
Under FFDCA section 408(g), 21 U.S.C. 346a, any person may file an
objection to any aspect of this regulation and may also request a
hearing on those objections. You must file your objection or request a
hearing on this regulation in accordance with the instructions provided
in 40 CFR part 178. To ensure proper receipt by EPA, you must identify
docket ID number EPA-HQ-OPP-2009-0676 in the subject line on the first
page of your submission. All objections and requests for a hearing must
be in writing, and must be received by the Hearing Clerk on or before
April 4, 2011. Addresses for mail and hand delivery of objections and
hearing requests are provided in 40 CFR 178.25(b).
In addition to filing an objection or hearing request with the
Hearing Clerk as described in 40 CFR part 178, please submit a copy of
the filing that does not contain any CBI for inclusion in the public
docket. Information not marked confidential pursuant to 40 CFR part 2
may be disclosed publicly by EPA without prior notice. Submit a copy of
your non-CBI objection or hearing request, identified by docket ID
number EPA-HQ-OPP-2009-0676, by one of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the on-line instructions for submitting comments.
Mail: Office of Pesticide Programs (OPP) Regulatory Public
Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania
Ave., NW., Washington, DC 20460-0001.
Delivery: OPP Regulatory Public Docket (7502P),
Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South
Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only
accepted during the Docket Facility's normal hours of operation (8:30
a.m. to 4 p.m., Monday through Friday, excluding legal holidays).
Special arrangements should be made for deliveries of boxed
information. The Docket Facility telephone number is (703) 305-5805.
II. Petition for Exemption
In the Federal Register of October 7, 2009 (74 FR 51597) (FRL-8792-
7), EPA issued a notice pursuant to section 408 of FFDCA, 21 U.S.C.
346a, announcing the filing of a pesticide petition (PP 9E7586) by
Whitmire Micro-Gen, c/o Landis International, P.O. Box 5126, Valdosta,
GA 31603-5126. The petition requested that 40 CFR 180.910 and 40 CFR
180.930 be amended by establishing an exemption from the requirement of
a tolerance for residues of isobutane (CAS Reg. No. 75-28-5) when used
as an inert ingredient (propellant) in pesticide formulations applied
pre- and post-harvest and pesticide formulations applied to animals.
That notice referenced a summary of the petition prepared by
Landis International, on behalf of Whitmire Micro-Gen, the petitioner,
which is available in the docket, http://www.regulations.gov. There
were no comments received in response to the notice of filing.
III. Inert Ingredient Definition
Inert ingredients are all ingredients that are not active
ingredients as defined in 40 CFR 153.125 and include, but are not
limited to, the following types of ingredients (except when they have a
pesticidal efficacy of their own): Solvents such as alcohols and
hydrocarbons; surfactants such as polyoxyethylene polymers and fatty
acids; carriers such as clay and diatomaceous earth; thickeners such as
carrageenan and modified cellulose; wetting, spreading, and dispersing
agents; propellants in aerosol dispensers; microencapsulating agents;
and emulsifiers. The term ``inert'' is not intended to imply
nontoxicity; the ingredient may or may not be chemically active.
Generally, EPA has exempted inert ingredients from the requirement of a
tolerance based on the low toxicity of the individual inert
IV. 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(b)(2)(A)(ii) of FFDCA defines
``safe'' to mean that ``there is a reasonable certainty that no harm
will result from aggregate exposure to the pesticide chemical residue,
including all anticipated dietary exposures and all other exposures for
which there is reliable information.'' This includes exposure through
drinking water and in residential settings, but does not include
occupational exposure. Section 408(b)(2)(C) of FFDCA requires EPA to
give special consideration to exposure of infants and children to the
pesticide chemical residue in establishing a tolerance and to ``ensure
that there is a reasonable certainty that no harm will result to
infants and children from aggregate exposure to the pesticide chemical
residue.* * *''
EPA establishes exemptions from the requirement of a tolerance only
in those cases where it can be clearly demonstrated that the risks from
aggregate exposure to pesticide chemical residues under reasonably
foreseeable circumstances will pose no appreciable risks to human
health. In order to determine the risks from aggregate exposure to
pesticide inert ingredients, the Agency considers the toxicity of the
inert in conjunction with possible exposure to residues of the inert
ingredient through food, drinking water, and through other exposures
that occur as a result of pesticide use in residential settings. If EPA
is able to determine that a finite tolerance is not necessary to ensure
that there is a reasonable certainty that no harm will result from
aggregate exposure to the inert ingredient, an exemption from the
requirement of a tolerance may be established.
Consistent with section 408(c)(2)(A) of FFDCA, and the factors
specified in FFDCA section 408(c)(2)(B), 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 isobutane including exposure
resulting from the exemption established by this action. EPA's
assessment of exposures and risks associated with isobutane follows.
A. Toxicological Profile
EPA has evaluated the available toxicity data and considered their
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
Isobutane is an asphyxiant and acute exposure may cause tachypnea
and tachycardia. While direct contact with the liquid may cause burns,
the vapor has no effects on the skin and eyes. Sudden death has also
been reported from abusive ``sniffing'' of products containing
isobutane, especially lighter refills. In a safety assessment of
isobutane as a cosmetic ingredient (1982), dermal irritation in humans
was very slight and transient erythema occurred randomly. Repeated
inhalation exposure did not result in any changes in
electroencephalograms, adrenocortical function, pulmonary function,
neurological response, subjective response, cardiac function or
Acute toxicity data on isobutane were limited to inhalation
exposure and eye and skin irritation. Isobutane was not acutely toxic
via the inhalation route and was basically non-irritating to the skin
and eyes of rabbits.
Several studies were found in which monkeys, rabbits, and rats were
exposed to formulations or to mixtures containing isobutane. No
toxicity was reported for two species of monkeys and one species of
rabbit exposed for 90 days to various formulations containing
No effects on survival, body weight, hematology, clinical
pathology, or liver and kidney weights were observed in rats exposed to
0, 1,000, or 4,500 ppm (equivalent to 0, 622 or 2,803 milligrams/
kilogram/day (mg/kg/day) of a 50:50 mixture of isobutane: isopentane
for 13 weeks, however clinical signs included hunched posture, lethargy
and crusted eyes in both exposure groups. There were no clinical signs
of toxicity observed and no gross or microscopic lesions seen in
Sprague-Dawley rats exposed to 0, 44, 432, or 4,437 ppm (equivalent to
0, 27, 269, or 2,763 mg/kg/day) of a mixture containing 25% each of n-
butane, isobutane, n-pentane, and isopentane for 3 weeks.
In a 4-week sub-chronic toxicity study combined with reproduction/
developmental toxicity screening and neurotoxicity screening study,
Sprague Dawley CD rats were treated with isobutane (purity 99.0%) to
assess the repeated dose, reproductive and developmental toxicity
potential of this material when administered by whole body inhalation
exposure. A no-observed-adverse effect level (NOAEL) of 9,000 ppm
(equivalent to 5,600 mg/kg/day) was concluded for general systemic/
neurotoxic (parental) endpoints in this study. Based on decreased male
and female fertility and increased post-implantation loss in the 9,000
ppm group, the fertility and reproductive endpoints NOAEL was
determined to be 3,000 ppm (equivalent to 1,867 mg/kg/day). There were
no effects on offspring survival, body weight and development up to
post-natal day 4. A NOAEL of 9,000 ppm (equivalent to 5,600 mg/kg/day)
was concluded for developmental effects. No effects on functional
observational battery parameters and motor activity were observed in
In terms of neurotoxicity, acute toxicity studies show effects on
the central nervous system (CNS) with rodents more sensitive than dogs.
Exposure to a concentration of 55% was lethal in dogs, while 41-52% was
lethal to mice within 2-3 minutes. The 10-minute EC50 for
CNS effects was listed as 200,000 ppm (equivalent to 124,560 mg/kg/day)
for the rat.
Several tests were found measuring the cardiopulmonary toxicity of
isobutane. No effects were seen in anesthetized Rhesus monkeys exposed
for 5 minutes to 5% isobutane through a tracheal cannula. Effects on
the heart were shown in the dog with concentration-related decreased
contractility, pressure, and output measured between 2-10% isobutane.
Mongrel dogs were also anesthetized and exposed to isobutane through a
tracheal cannula. Blood pressure and heart rate were not affected by
exposure. All concentrations significantly increased pulmonary
resistance and decreased pulmonary compliance. Similarly, anesthetized
male Osburn-Mendel rats exposed to 27% isobutane showed apnea after 8.7
minutes of exposure followed by cardiac arrest; decreased respiratory
rate, tidal volume, and pulmonary compliance and increased airway
resistance were also found. In another test with anesthetized male
Swiss mice, 20-40% isobutane did not induce cardiac arrhythmia, but did
sensitize the heart to epinephrine-induced arrhythmia.
No evidence of an increase in mutation frequency was found in five
strains of Salmonella typhimurium exposed to up to 50% isobutane in
air. Strains TA98, TA100, TA1535, TA1537, and TA1538 were exposed for 6
hours with and without metabolic activation. No chronic toxicity or
carcinogenicity studies with isobutane were identified. However, the
concern for carcinogenicity is low based on rapid metabolism, lack of
mutagenicity and lack of systemic toxicity at doses up to 1,867 mg/kg/
day. In addition, the Agency used a qualitative structure activity
relationship (SAR) database, DEREK11, to determine if there were
structural alerts suggestive of carcinogenicity. No structural alerts
Specific information on the studies received and the nature of the
adverse effects caused by, 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 in the
document ``PC Code 800015: Isobutane (CAS Reg. No. 75-28-5); Human
Health Risk Assessment and Ecological Effects Assessment to the Support
Proposed Exemption from the Requirement of a Tolerance When Used as an
Inert Ingredient in Pesticide Formulations'' at  in docket ID number
B. Toxicological Points of Departure/Levels of Concern
Due to the low potential hazard of isobutane, quantitative dietary,
occupational and residential exposure assessments are not necessary. In
a 4-week sub-chronic toxicity study combined with reproduction/
developmental toxicity screening and neurotoxicity screening study,
exposure of male and female rats to target concentrations of 900, 3,000
or 9,000 ppm (equivalent to 560, 1,867, and 5,600 mg/kg/day) of
isobutane by whole-body inhalation for four weeks resulted in no
general systemic/neurotoxic effects. Based on decreased male and female
fertility and increased post-implantation loss in the 5,600 mg/kg/day
group, the fertility and reproductive endpoints NOAEL was determined to
be 1,867 mg/kg/day. There were no effects on offspring survival, body
weight and development up to post-natal day 4. A NOAEL of 5,600 mg/kg/
day was concluded for developmental effects. Since no toxicity was
observed at high doses, quantitative risk assessment is deemed
C. Exposure Assessment
No hazard was identified for the acute and chronic dietary
assessment (food and drinking water), or for the short-, intermediate-,
and long-term residential assessments, and therefore no aggregate risk
assessments were performed. Available toxicological studies indicate
lack of systemic toxicity at doses up to 1,867 mg/kg/day. Therefore, no
quantitative dietary or occupational and residential risk assessment
1. Dietary exposure from food and feed uses and drinking water. In
evaluating dietary exposure to isobutane, EPA considered exposure under
the proposed exemption from the requirement of a tolerance. Since
toxicity effects were seen only at high doses for isobutane, a
quantitative exposure assessment for isobutane was not conducted. Any
possible dietary exposure to isobutane from its use as an inert
ingredient in pesticide products would be through consumption of food
to which pesticide products containing it have been applied and
possibly through drinking water (from runoff). Isobutane is expected to
exist in the atmosphere as a gas and volatilize rapidly from surface
water and soil. This will reduce the amount of isobutane that is
available for uptake by plants. Run-off into surface water is not
anticipated due to rapid volatization, and therefore, contributions of
concern to drinking water are not expected.
2. 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).
Isobutane is widely used as a propellant in a variety of household
products, such as cleaners and air fresheners. It is also used in
nonfood use insecticide products and personal care products.
Considering the low toxicity of isobutane, residues of concern are not
anticipated from residential exposures (inhalation and dermal) and
therefore a quantitative aggregate risk assessment was not performed.
3. Cumulative effects from substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when
considering whether to establish, modify, or revoke a tolerance, the
Agency consider ``available information'' concerning the cumulative
effects of a particular pesticide's residues and ``other substances
that have a common mechanism of toxicity.''
EPA has not found isobutane to share a common mechanism of toxicity
with any other substances, and does not appear to produce a toxic
metabolite produced by other substances. For the purposes of this
tolerance action, therefore, EPA has assumed that isobutane does not
have a common mechanism of toxicity with other substances. For
information regarding EPA's efforts to determine which chemicals have a
common mechanism of toxicity and to evaluate the cumulative effects of
such chemicals, see EPA's Web site at http://www.epa.gov/pesticides/cumulative.
D. Safety Factor for Infants and Children
Section 408 of the FFDCA provides that EPA shall apply an
additional tenfold (10X) margin of safety for infants and children in
the case of threshold effects to account for prenatal and postnatal
toxicity and the completeness of the database on toxicity and exposure
unless EPA determines that a different margin of safety will be safe
for infants and children. This additional margin of safety is commonly
referred to as the FQPA safety factor (SF). In applying this provision,
EPA either retains the default value of 10X or uses a different
additional safety factor when reliable data available to EPA supports
the choice of a different factor.
The toxicity database is sufficient for isobutane and potential
exposure is adequately characterized given the low toxicity of the
chemical. In terms of hazard, there are low concerns and no residual
uncertainties regarding prenatal and/or postnatal toxicity. In the OECD
422 study via the inhalation route, the NOAEL for general systemic
toxicity and neurotoxicity was 5,600 mg/kg/day (the highest dose
tested). Based on decreased male and female fertility and increased
post-implantation loss in the
5,600 mg/kg/day group, the fertility and reproductive endpoints NOAEL
was determined to be 1,867 mg/kg/day. There were no effects on
offspring survival, body weight and development up to post-natal day 4.
A NOAEL of 5,600 mg/kg/day was concluded for developmental effects.
Based on this information, there is no concern at this time for
increased sensitivity to infants and children to isobutane when used as
an inert ingredient in pesticide formulations and a safety factor
analysis has not been used to assess risk. For the same reason, EPA has
determined that an additional safety factor is not needed to protect
the safety of infants and children.
E. Aggregate Risks and Determination of Safety
Given the lack of concern for hazard posed by isobutane, EPA
concludes that there are no dietary or aggregate dietary/non-dietary
risks of concern as a result of exposure to isobutane in food and water
or from residential exposure. Residues of concern are not anticipated
for dietary exposure (food and drinking water) or for residential
exposure (dermal and inhalation) from the use of isobutane as an inert
ingredient in pesticide products. As discussed above, EPA expects
aggregate exposure to isobutane to pose no appreciable dietary risk
given that the data show a lack of any systemic toxicity at doses up to
1,867 mg/kg/day and a lack of any apparent developmental effects.
Taking into consideration all available information on isobutane,
EPA has determined that there is a reasonable certainty that no harm to
any population subgroup, including infants and children, will result
from aggregate exposure to isobutane under reasonable foreseeable
circumstances. Therefore, the establishment of an exemption from
tolerance under 40 CFR 180.910 for residues of isobutane when used as
an inert ingredient in pesticide formulations applied pre- and post-
harvest and under 40 CFR 180.930 for residues of isobutane when used as
an inert ingredient in pesticide formulations applied to animals, is
safe under FFDCA section 408.
V. Other Considerations
A. Analytical Enforcement Methodology
An analytical method is not required for enforcement purposes since
the Agency is establishing an exemption from the requirement of a
tolerance without any numerical limitation.
B. International Residue Limits
In making its tolerance decisions, EPA seeks to harmonize U.S.
tolerances with international standards whenever possible, consistent
with U.S. food safety standards and agricultural practices. EPA
considers the international maximum residue limits (MRLs) established
by the Codex Alimentarius Commission (Codex), as required by FFDCA
section 408(b)(4). The Codex Alimentarius is a joint U.N. Food and
Agriculture Organization/World Health Organization food standards
program, and it is recognized as an international food safety
standards-setting organization in trade agreements to which the United
States is a party. EPA may establish a tolerance that is different from
a Codex MRL; however, FFDCA section 408(b)(4) requires that EPA explain
the reasons for departing from the Codex level.
The Codex has not established a MRL for isobutane.
Therefore, an exemption from the requirement of a tolerance is
established under 40 CFR 180.910 and 40 CFR 180.930 for isobutane (CAS
Reg. No. 75-28-5) when used as an inert ingredient (propellant) in
pesticide formulations applied pre- and post-harvest and when applied
VII. 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, 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) (Pub. L. 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
VIII. 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
List of Subjects in 40 CFR Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
Dated: January 24, 2011.
Director, Registration Division, Office of Pesticide Programs.
Therefore, 40 CFR chapter I is amended as follows:
1. The authority citation for part 180 continues to read as follows:
Authority: 21 U.S.C. 321(q), 346a and 371.
2. In the table to Sec. 180.910 add alphabetically a new inert
ingredient to read as follows:
Sec. 180.910 Inert ingredients used pre- and post-harvest; exemptions
from the requirement of a tolerance.
* * * * *
Inert ingredients Limits Uses
* * * * * * *
Isobutane (CAS Reg. No. 75-28-5) None.............. Propellant.
* * * * * * *
3. In the table to Sec. 180.930, add alphabetically a new inert
ingredient to read as follows:
Sec. 180.930 Inert ingredients applied to animals; exemptions from
the requirement of a tolerance.
* * * * *
Inert ingredients Limits Uses
* * * * * * *
Isobutane (CAS Reg. No. 75-28-5) None.............. Propellant.
* * * * * * *
[FR Doc. 2011-2265 Filed 2-1-11; 8:45 am]
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