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potassium dihydrogen phosphate Proposed Tolerance Requirement Exemption 2/98


[Federal Register: March 3, 1998 (Volume 63, Number 41)]
[Proposed Rules]               
[Page 10352-10354]
>From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr03mr98-24]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-300618; FRL-5772-4]
RIN 2070-AB18

 
Potassium Dihydrogen Phosphate; Proposed Exemption from the 
Requirement of a Tolerance

AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.

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SUMMARY: EPA proposes to establish an exemption from the requirement of 
a tolerance for residues of potassium dihydrogen phosphate 
(KH<INF>2</INF>PO<INF>4</INF>) in or on all food commodities, when 
applied as a fungicide in accordance with good agricultural practices 
to control powdery mildew in fruits and vegetables. EPA is proposing 
this regulation on its own initiative.

DATES: Comments, identified by the docket control number [OPP-300618] 
must be received on or before May 4, 1998.

ADDRESSES: By mail, submit written comments to: Public Information and 
Records Integrity Branch, Information Resources and Services Division 
(7502C), Office of Pesticide Programs, Environmental Protection Agency, 
401 M St., SW., Washington, DC 20460. In person, deliver comments to: 
Rm. 119, CM #2, 1921 Jefferson Davis Highway, Arlington, VA.
    Comments and data may also be submitted electronically to: opp-
docket@epamail.epa.gov. Follow the instructions under Unit IV of this 
document. No Confidential Business Information (CBI) should be 
submitted through e-mail.
    Information submitted as a comment concerning this document may be 
claimed confidential by marking any part or all of that information as 
CBI. Information so marked will not be disclosed except in accordance 
with procedures set forth in 40 CFR part 2. A copy of the comment that 
does not contain CBI must be submitted for inclusion in the public 
record. Information not marked confidential will be included in the 
public docket by EPA without prior notice. The public docket is 
available for public inspection in Rm. 119 at the Virginia address 
given above, from 8:30 a.m. to 4 p.m., Monday through Friday, excluding 
legal holidays.
FOR FURTHER INFORMATION CONTACT: By mail: Suku Oonnithan, c/o Product 
Manager (PM) 91, Biopesticides and Pollution Prevention Division 
(7511W), Office of Pesticide Programs, Environmental Protection Agency, 
401 M St., SW., Washington, DC 20460. Office location; telephone 
number; and e-mail address: Crystal Station #1, 5th Floor, 2800 Crystal 
Drive, Arlington, VA 22202; 703-308-9524; 
oonnithan.suku@epamail.epa.gov.

SUPPLEMENTARY INFORMATION: Pursuant to section 408(e) of the Federal 
Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. section 346a(d), EPA 
proposes to amend 40 CFR part 180 by establishing an exemption from the 
requirement of a tolerance for residues of potassium dihydrogen 
phosphate in or on all food commodities.

I. Risk Assessment and Statutory Authority

    New section 408(c)(2)(A)(i) of FFDCA allows EPA to establish an 
exemption from the requirement of a tolerance (the legal limit for a 
pesticide chemical residue in or on a food commodity) only if EPA 
determines that the tolerance is ``safe.'' Section 408(c)(2)(A)(ii) 
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.'' These include 
exposure through drinking water and in residential settings, but does 
not include occupational exposure. Section 408(b)(2)(B) requires EPA to 
give special consideration to exposure of infants and children to the 
pesticide chemical residue in establishing an exemption 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 performs a number of analyses to determine the risks 
from aggregate exposure to pesticide residues. First, EPA determines 
the toxicity of pesticides. Second, EPA examines exposure to the 
pesticide through food, drinking water, and through other exposures 
that occur as a result of pesticide use in residential settings.

II. Risk Assessment and Statutory Findings

    Consistent with section 408(b)(2)(D) of FFDCA, EPA has reviewed the 
available scientific data and other relevant information in support of 
this action and considered its validity, completeness, reliability, and 
relationship 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.

A. Toxicological Profile

     Potassium dihydrogen phosphate is a naturally occurring mineral 
and is widely used as a fertilizer with no reported adverse effects. 
The acute toxicological data available on potassium dihydrogen 
phosphate include: acute oral toxicity in rats (LD<INF>50</INF> > 500 
mg/kg and Toxicity Category III), acute dermal toxicity in rabbits 
(LD<INF>50</INF> > 2,000 mg/kg and Toxicity Category III), primary eye 
irritation in rabbits (Toxicity Category III), and primary skin 
irritation in rabbits (Toxicity Category IV).
     Phosphate is ubiquitous and abundant in biological materials. Most 
of the phosphate ingested by humans and animals is converted to 
orthophosphate, both as H<INF>2</INF>PO<INF>4</INF> and HPO<INF>4</INF> 
in the digestive tract, prior to absorption in the small intestine. 
Phosphate is found in blood, cytoplasm, bone, teeth, urine, and feces. 
It is essential in the tightly regulated physiological and metabolic 
processes of energy production, carbohydrate metabolism, iron 
absorption, plasma buffering, maintenance of certain hormone levels, 
and muscular contraction. Phosphates are molecular components of 
phospholipids, nucleic acids, energy generating compounds, certain 
sugars, and some proteins. Dietary phosphate, that is not absorbed is 
passed through the body via the feces and the absorbed excess phosphate 
is excreted renally via the urine.
     Potassium also is ubiquitous in nature and in biological systems. 
It is an essential cationic component of body fluids and cytoplasm. It 
is essential for amino acid and sugar transport, cell permeability, 
muscle contraction, and is required as a cofactor for certain enzymes. 
Excess potassium is excreted in the urine. Potassium also is found in

[[Page 10353]]

saliva, sweat, tears, and in gastric secretions and fluids.
     Potassium phosphate is widely used as a fertilizer. Therefore it's 
use as a pesticide is not likely to significantly increase exposure 
that already occurs in the diet from natural sources, including 
drinking water. While deficiencies of potassium and phosphate may 
adversely impact human health, excessive intake via natural exposures 
does not.

B. Aggregate Exposure

    In examining aggregate exposure, FQPA directs EPA to consider 
available information concerning exposures from the pesticide residue 
in food and all other non-occupational exposures, including drinking 
water from groundwater or surface water and exposure through pesticide 
use in gardens, lawns, or buildings (residential and other indoor 
uses).
    1. Dietary exposure--i. Food. It is anticipated that no significant 
residues of potassium dihydrogen phosphate will occur in treated foods 
other than that present as a mineral and as mineral complexes 
manufactured by the plant through photosynthesis and enzymatic 
processes.
    ii. Drinking water exposure. Potassium dihydrogen phosphate is used 
as an agricultural fertilizer. Exposure to its residues in drinking 
water from pesticidal use is not expected to be significant or harmful 
to human health.
    2. Other non-occupational exposure--i. Dermal exposure. No undue 
risk is expected as a result of the use of potassium dihydrogen 
phosphate as a fungicide.
    ii. Inhalation exposure: None expected as a result of the use of 
potassium dihydrogen phosphate as a fungicide.

C. Cumulative Exposure to Substances with 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 
considers ``available information concerning the cumulative effects of 
a particular pesticide's residues'' and ``other substances that have a 
common mechanism of toxicity.'' The Agency believes that ``available 
information'' in this context might include not only toxicity, 
chemistry, and exposure data, but also scientific policies and 
methodologies for understanding common mechanisms of the toxicity for 
conducting cumulative risk assessments. For most pesticides, although 
the Agency has some information in its files that may turn out to be 
helpful in eventually determining whether a pesticide shares a common 
mechanism of toxicity with any other substances, EPA does not at this 
time have the methodologies to resolve the complex scientific issues 
concerning common mechanisms of toxicity in a meaningful way. EPA has 
begun a pilot process to study this issue further through the 
examination of particular classes of pesticides. The Agency hopes the 
results of this pilot process will increase the Agency's scientific 
understanding of this question such that EPA will be able to develop 
and apply scientific principles for better determining which chemicals 
have a common mechanism of toxicity for evaluating the cumulative 
effects of such chemicals. The Agency anticipates, however, that even 
as its understanding of the science of common mechanism of toxicity 
increases, decisions on specific classes of chemicals will be heavily 
dependent on chemical specific data, much of which may not be presently 
available.
    Although at present the Agency does not know how to apply the 
information in its files concerning common mechanism issues to most 
risk assessments, there are pesticides as to which the common mechanism 
can be resolved. These include pesticides that are toxicologically and 
structurally dissimilar to existing chemical substances (in which case 
the Agency can conclude that it is unlikely that a pesticide shares a 
common mechanism of activity with other substances) and pesticides that 
produce a common toxic metabolite (in which case common mechanism of 
activity will be assumed).
     Potassium dihydrogen phosphate does not share any common 
mechanisms of toxicity with other pesticide chemicals. Its use as a 
fungicide should not significantly increase exposure to other uses as 
an agricultural fertilizer. Therefore, no impact on the potential for 
toxic effects from the pesticidal use of potassium dihydrogen phosphate 
is expected.

D. Safety Determinations

    1. U.S. population. Potassium dihydrogen phosphate has low 
mammalian toxicity and EPA has exempted it from tolerance when used as 
an inert ingredient as a buffering agent in pesticide formulations (40 
CFR 180.1001(d)). The subject chemical occurs in nature and has been 
used as a fertilizer for many years with no reported adverse effects. 
Based on available information, the Agency believes that exposure to 
this chemical will not pose any appreciable risks to human health.
    2. Infants and children. Section 408 of FFDCA provides that EPA 
shall apply an additional tenfold margin of exposure (safety) for 
infants and children in the case of threshold effects to account for 
pre- and post-natal toxicity and the completeness of the database, 
unless EPA determines that a different margin of exposure (safety) will 
be safe for infants and children. Margins of exposure (safety) are 
often referred to as uncertainty (safety) factors. In this instance, 
the Agency believes that there is reliable data to support that 
potassium dihydrogen phosphate is practically non-toxic to mammals, 
including infants and children, and, thus, there are no threshold 
effects, and EPA has not used a margin of exposure (safety) approach to 
assess the safety of potassium dihydrogen phosphate. As a result, the 
provision requiring an additional margin of exposure (safety) does not 
apply.

E. Other Considerations

    1. Endocrine disruptors. There are no reports of any estrogenic and 
other adverse effects to human population as a result of the use of 
potassium dihydrogen phosphate as an agricultural fertilizer. Based on 
this information combined with its low mammalian toxicity, EPA 
concludes that there is a reasonable certainty that no adverse 
endocrine effects will result from the use of potassium dihydrogen 
phosphate as a fungicide.
    2. Analytical method(s). Since the Agency proposes to establish an 
exemption from the requirement of a tolerance without any numerical 
limitation, the Agency has concluded that an analytical method is not 
required for enforcement purposes for the residues of potassium 
dihydrogen phosphate.

F. Existing Tolerances

     No existing tolerances or exemptions from the requirement of a 
tolerance have been issued for potassium dihydrogen phosphate as an 
active ingrdient in the United States.

G. International Tolerances

     There are no CODEX tolerances or international tolerance 
exemptions for potassium dihydrogen phosphate.

H. Conclusion

     Based on the information and data considered, EPA is proposing 
that an exemption from the requirement of a tolerance be established as 
set forth below.
    Consistent with section 408(b)(2)(D) of FFDCA, EPA has reviewed the

[[Page 10354]]

available scientific data and other relevant information in support of 
this action. Based on the information and data considered, the Agency 
has determined that, in amending 40 CFR part 180 as proposed, there is 
reasonable certainty that no harm to the general population including 
infants and children will result from aggregate exposure to the 
pesticide chemical residue.

III. Comments

    Under FFDCA section 408(e)(2), EPA must provide for a public 
comment period before issuing a final tolerance or tolerance exemption 
under section 408(e)(1). The public comment period is to be for 60 days 
unless the Administrator for good cause finds that it is in the public 
interest to reduce that comment period.

IV. Public Docket and Electronic Submissions

    The official record for this rulemaking, as well as the public 
version, has been established for this rulemaking under docket control 
number [OPP-300618] (including comments and data submitted 
electronically as described below). A public version of this record, 
including printed, paper versions of electronic comments, which does 
not include any information claimed as CBI, is available for inspection 
from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal 
holidays. The official rulemaking record is located at the Virginia 
address in ``ADDRESSES'' at the beginning of this document.
    Electronic comments can be sent directly to EPA at:
    opp-docket@epamail.epa.gov

    Electronic comments must be submitted as an ASCII file avoiding the 
use of special characters and any form of encryption. Comment and data 
will also be accepted on disks in Wordperfect 5.1/6.1 or ASCII file 
format. All comments and data in electronic form must be identified by 
the docket control number [OPP-300618]. Electronic comments on this 
proposed rule may be filed online at many Federal Depository Libraries.

V. Regulatory Assessment Requirements

    This action proposes an exemption from the tolerance requirement 
under FFDCA section 408(e). 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). In addition, this proposed rule does not contain any information 
collections subject to OMB approval under the Paperwork Reduction Act 
(PRA), 44 U.S.C. 3501 et seq., or impose any enforceable duty or 
contain any unfunded mandate as described under Title II of the 
Unfunded Mandates Reform Act of 1995 (UMRA) (Pub. L. 104-4). Nor does 
it require any prior consultation as specified by Executive Order 
12875, entitled Enhancing the Intergovernmental Partnership (58 FR 
58093, October 28, 1993), or special considerations as required by 
Executive Order 12898, entitled Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations (59 FR 7629, February 16, 1994), or require special OMB 
review in accordance with Executive Order 13045, entitled Protection of 
Children from Environmental Health Risks and Safety Risks (62 FR 19885, 
April 23, 1997).
    In addition, under the Regulatory Flexibility Act (RFA) (5 U.S.C. 
601 et seq.), the Agency previously assessed whether establishing 
tolerances, exemptions from tolerances, raising tolerance levels or 
expanding exemptions might adversely impact small entities and 
concluded, as a generic matter, that there is no adverse economic 
impact. The factual basis for the Agency's generic certification for 
tolerance actions was published on May 4, 1981 (46 FR 24950), and was 
provided to the Chief Counsel for Advocacy of the Small Business 
Administration.

 VI. Submission to Congress and the General Accounting Office

    Under 5 U.S.C. 801(a)(1)(A), as added by the Small Business 
Regulatory Enforcement Fairness Act of 1996, the Agency has submitted a 
report containing this rule and other required information to the U.S. 
Senate, the U.S. House of Representatives, and the Comptroller General 
of the General Accounting Office prior to publication of this rule in 
today's Federal Register. This is not a ``major rule'' as defined by 5 
U.S.C. 804(2).

List of Subjects in 40 CFR Part 180

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Pesticides and pests, Reporting and record 
keeping requirements.

    Dated: February 18, 1998.

Janet L. Andersen,

Director, Biopesticides and Pollution Prevention Division, Office of 
Pesticide Programs.
    Therefore, it is proposed that 40 CFR chapter I be amended as 
follows:

PART 180--[AMENDED]

    1. The authority citation for part 180 continues to read as 
follows:
    Authority: 21 U.S.C. 346a and 371.


    2. Section 180.1193 is added to subpart D to read as follows:


Sec. 180.1193  Potassium dihydrogen phosphate; exemption from the 
requirement of a tolerance.

    Potassium dihydrogen phosphate is exempted from the requirement of 
a tolerance in or on all food commodities when applied as a fungicide 
in accordance with good agricultural practices.
[FR Doc. 98-5418 Filed 3-2-98; 8:45 am]
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