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Potassium Hypochlorite; Exemption From the Requirement of a Tolerance

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Information about this document as published in the Federal Register.

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Environmental Protection Agency (EPA).


Final rule.


This regulation establishes the exemption from the requirement of a tolerance for residues of Potassium hypochlorite. Enviro Tech Chemical Services, Inc. submitted a petition to EPA under the Federal Food, Drug, and Cosmetic Act (FFDCA), requesting that Potassium hypochlorite in end-use products be eligible for the exemption from the requirement of a tolerance.

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This regulation is effective March 2, 2011. Objections and requests for hearings must be received on or before May 2, 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.


EPA has established a docket for this action under docket identification (ID) number EPA-HQ-OPP-2009-0996. All documents in the docket are listed in the docket index available at 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, 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.

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Wanda Henson, Antimicrobials Division (7510P), Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone number: (703) 308-6345; e-mail address:

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I. General Information

A. Does this action apply to me?

You may be potentially affected by this action if you are a 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 31212).

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 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​ecfr.

C. How can I file an objection or hearing request?

Under FFDCA section 408(g), 21 U.S.C. 346a, any person may file an objection to any aspect of this regulation and may also request a hearing on those objections. You must file your objection or request a hearing on this regulation in accordance with the instructions provided in 40 CFR part 178. To ensure proper receipt by EPA, you must identify docket ID number EPA-HQ-OPP-2009-0996 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 May 2, 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-2009-0996, by one of the following methods:

  • Federal eRulemaking Portal: Follow the on-line instructions for submitting comments.
  • Mail: Office of Pesticide Programs (OPP) Regulatory Public Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001.
  • Delivery: OPP Regulatory Public Docket (7502P), Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only accepted during the Docket Facility's normal hours of operation (8:30 a.m. to 4 p.m., Monday through Friday, excluding legal holidays). Special arrangements should be made for deliveries of boxed information. The Docket Facility telephone number is (703) 305-5805.

II. Summary of Petitioned-For Exemption

In the Federal Register of Wednesday, January 12, 2011 (76 FR 2110) (FRL-8860-9), 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 0F7767) by Enviro Tech Chemical Services, Inc, Modesto, CA 95358. The petition requested that 40 CFR part 180 be amended to establish an exemption from the requirement of a tolerance for potassium hypochlorite in or on apple; artichoke; asparagus; brussel sprouts; carrot; cauliflower; celery; cherry; cabbage; lettuce; fruits, citrus; cucumber; onion, green; melon; peach; nectarine; plum; pear; pepper, bell; potato; radish; fruit, stone; and tomato. That notice referenced a summary of the petition prepared by Enviro Tech Chemical Services, Inc., the registrant, which is available in the docket, 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 exemption 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 Start Printed Page 11342support of this action. EPA has sufficient data to assess the hazards of and to make a determination on aggregate exposure for Potassium hypochlorite, including exposure resulting from the exemption established by this action. EPA's assessment of exposures and risks associated with potassium hypochlorite 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 potassium hypochlorite is available in the docket,

The Agency conducted an in-depth review of the similarities between potassium hypochlorite and the existing registered active ingredients, sodium hypochlorite and calcium hypochlorite. Based upon this review, the Agency determined that the data available to support the registrations of these active ingredients are also applicable to potassium hypochlorite. No additional generic or product-specific acute, chronic or subchronic toxicological studies were required to be submitted in support of this application. All toxicology data were bridged from studies on sodium and calcium hypochlorite based on their chemical similarity.

Potassium hypochlorite is corrosive and can cause severe damage to the eyes and skin. Potassium hypochlorite has been assigned a Toxicity Category I, indicating the highest degree of toxicity for these acute effects. In the presence of oxygen, however, these compounds react easily with organic matter and convert readily into potassium chloride due to their simple chemical nature and structure. Exemptions from the requirement of a tolerance have been established for sodium and calcium hypochlorite used both as food contact surface sanitizers (40 CFR 180.940) and as antimicrobials used on raw agricultural commodities (40 CFR 180.1054 and 180.1235). Widely used in disinfecting water supplies for nearly a century, the hypochlorite class of chemicals has proven safe and practical to use provided that necessary precautions are taken by the user to prevent the eye and skin irritation which are inherent to all strong oxidizing agents. All documents related to this case can be found at in the document “Antimicrobial Pesticide Products; Registration Applications” page 16110 in docket ID number EPA-HQ-OPP-2009-0996.

B. Toxicological Points of Departure/Levels of Concern for Potassium Hypochlorite

Once a pesticide's toxicological profile is determined, EPA identifies toxicological points of departure (POD) and levels of concern to use in evaluating the risk posed by human exposure to the pesticide. For hazards that have a threshold below which there is no appreciable risk, the toxicological POD is used as the basis for derivation of reference values for risk assessment. PODs are developed based on a careful analysis of the doses in each toxicological study to determine the dose at which no adverse effects are observed (the NOAEL) and the lowest dose at which adverse effects of concern are identified (the LOAEL). Uncertainty/safety factors are used in conjunction with the POD to calculate a safe exposure level—generally referred to as a population-adjusted dose (PAD) or a reference dose (RfD)—and a safe margin of exposure (MOE). For non-threshold risks, the Agency assumes that any amount of exposure will lead to some degree of risk. Thus, the Agency estimates risk in terms of the probability of an occurrence of the adverse effect in a lifetime. For more information on the general principles EPA uses in risk characterization and a complete description of the risk assessment process, see​pesticides/​factsheets/​riskassess.htm.

C. Exposure Assessment

1. Dietary exposure from food and feed uses. In evaluating dietary exposure to potassium hypochlorite, EPA considered exposure under the petitioned-for exemption. EPA assessed dietary exposures from potassium hypochlorite in food as follows:

Residues of potassium hypochlorite may remain on certain food crops as a result of their disinfectant uses. However, these residues pose no dietary risks of concern to human health based on data bridged from sodium hypochlorite. Therefore, a dietary risk assessment for potential exposures to residues in food is unwarranted.

2. Dietary exposure from drinking water. Residues of potassium hypochlorite that may remain in drinking water as a result of the use of this chemical are not expected to pose dietary risks of concern to human health based on data bridged from sodium hypochlorite.

3. 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). Potassium hypochlorite is currently registered for the following residential non-dietary sites: Swimming pools, spa and hot tubs, hard, non-porous and porous surfaces, and laundry.

Although residential exposure to mixer/loader/applicators is likely from the proposed uses of potassium hypochlorite, a quantitative risk assessment is not required because adverse systemic effects attributable to the dermal and inhalation routes of exposure to potassium hypochlorite are not expected based on toxicity data bridged from sodium hypochlorite.

Label precautionary statements and the requirement that applicators wear certain personal protective equipment (goggles or face shield and rubber gloves) are sufficient to protect users from the localized, irritation effects of exposure to potassium hypochlorite. In addition, the label states that users of swimming pools may not enter treated water until the residual chlorine is measured to be between 1 ppm and 3 ppm in order to prevent acute irritation effects.

Further information regarding EPA standard assumptions and generic inputs for residential exposures may be found at​pesticides/​trac/​science/​trac6a05.pdf.

4. Cumulative effects from substances with a common mechanism of toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when considering whether to establish, modify, or revoke a tolerance, the Agency consider “available information” concerning the cumulative effects of a particular pesticide's residues and “other substances that have a common mechanism of toxicity.”

EPA has not found potassium hypochlorite to share a common mechanism of toxicity with any other substances, and potassium hypochlorite does not appear to produce a toxic metabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has assumed that Potassium hypochlorite 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 Start Printed Page 11343chemical, see EPA's Web site at​pesticides/​cumulative.

D. Safety Factor for Infants and Children

Because potassium hypochlorite was of very low systemic toxicity, EPA did not use a safety factor analysis for assessing risk. For similar reasons, the additional safety factor for the protection of infants and children is not necessary.

E. Aggregate Risks and Determination of Safety

Based on the toxicity profile and exposure scenarios for potassium hypochlorite, EPA believes that the risks from dietary exposures to this pesticide would be minimal and without consequence to human health. Although residential use of potassium hypochlorite poses potential risks for acute eye and skin injury, it is not appropriate to aggregate the exposure related to these surface irritation effects with systemic exposure from dietary ingestion. In any event, the Agency believes that these acute risks will be sufficiently mitigated by precautionary labeling requiring protection of eyes and skin while using this pesticide.

Based on the toxicological and exposure data discussed in this preamble, EPA concludes that potassium hypochlorite will not pose a risk under reasonably foreseeable circumstances. Accordingly, EPA finds that there is a reasonable certainty of no harm will result to the general population, or to infants and children, from aggregate exposure to potassium hypochlorite residues.

IV. 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 potassium hypochlorite.

V. Conclusion

Therefore, an exemption is established for residues of potassium hypochlorite.

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, 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), Pub. L. 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).

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List of Subjects in 40 CFR Part 180

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Dated: February 23, 2011.

Joan Harrigan Farrelly,

Director, Antimicrobials Division, Office of Pesticide Programs.

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Therefore, 40 CFR chapter I is amended as follows:

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

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

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2. Section 180.1300 is added to subpart D to read as follows:

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Potassium hypochlorite; exemption from the requirement of a tolerance.

An exemption from the requirement of a tolerance is established for residues Start Printed Page 11344of potassium hypochlorite in or on all commodities.

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[FR Doc. 2011-4534 Filed 3-1-11; 8:45 am]