[Federal Register Volume 59, Number 17 (Wednesday, January 26, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-1615]


[[Page Unknown]]

[Federal Register: January 26, 1994]


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ENVIRONMENTAL PROTECTION AGENCY

[OPP-50573; FRL-4755-1]

 

Arthropod Pheromones in Solid Matrix Dispensers; Experimental Use 
Permits

AGENCY: Environmental Protection Agency (EPA)


ACTION: Notice.

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SUMMARY: EPA is announcing in this notice that it is expanding the 
acreage cut-off for when an Experimental Use Permit (EUP) is required 
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 
from 10 acres to 250 acres for a class of biological pesticides. This 
class of pesticides covers arthropod pheromone products in solid matrix 
dispensers used at rates at or below a total use rate of 150 grams 
active ingredient (AI)/acre/year. Tests conducted on these pheromone 
formulations under the conditions specified in this notice would not 
require an EUP at acreages up to and including 250 acres. Tests 
conducted on acreages exceeding 250 acres would require an EUP.

FOR FURTHER INFORMATION CONTACT: By mail: Phil Hutton, Registration 
Division, (7505C), Environmental Protection Agency, 401 M St., SW., 
Washington, DC 20460. Office location and telephone number: Rm. 213, 
Crystal Mall #2, 1921 Jefferson Davis Highway, Arlington, VA, 707-305-
7690.

SUPPLEMENTARY INFORMATION:

I. Introduction

    In keeping with the Administrator's commitment to reduce the use of 
higher risk pesticides and provide incentives for the adoption of 
lower-risk pest management methods, EPA is announcing in this notice a 
new policy of allowing testing of pheromones in solid matrix dispensers 
(e.g., twist ties, plastic tapes, and ropes) on no more than 250 acres 
to proceed without an EUP. EPA recognizes that alternative pest control 
strategies, integrated pest management, and reduced risk pesticides, 
such as pheromones in solid matrix dispensers, are fundamental elements 
of an overall program to reduce risks to humans and the environment.
    Insect species utilize certain volatile compounds, semiochemicals, 
and pheromones, to communicate with each other (e.g., to locate and 
attract mates or give alarm). For purposes of this notice, EPA defines 
a semiochemical as a chemical that transmits messages between living 
organisms. A pheromone, which is a type of semiochemical, is defined as 
a compound produced by an arthropod which, alone or in combination with 
other such compounds, modifies the behavior of other individuals of the 
same species (40 CFR 152.25(b)(1)). Even very low amounts of these 
naturally occurring volatile compounds can confuse normal insect 
behavior thus interrupting mating and preventing reproduction.
    These chemicals may pose a relatively low risk alternative for 
managing insect pest populations. The use of semiochemicals, including 
pheromones, to attract and trap insects has been a viable pest 
management technology for a considerable period of time. In 1979, EPA 
first registered pheromones for use in traps for the purpose of mass 
trapping Japanese Beetles. Since then, the Agency has registered 
approximately 30 semiochemical pesticides with approximately 20 active 
ingredients being Lepidoptera pheromones.
    It was in the late 1970s that EPA recognized that biochemical 
pesticides, including pheromones, were inherently different from most 
broad spectrum conventional pesticides and encouraged their development 
and registration, considering them to be potentially lower risk 
alternatives to conventional synthetic products on the market. The 
development of reduced safety data requirements currently in place for 
the registration of biochemical pesticides is based on the Agency's 
classification of a biochemical pesticide by two criteria: (1) The 
compound's non-toxic mode of action on the target pest, and (2) the 
natural occurrence of the compound. While not criteria for biochemical 
classification, arthropod pheromone products also have a low use rate, 
usually below 20 grams per acre, and target species specificity, 
therefore less expected environmental impact than other pesticides.
    The conditions under which an EUP, the first step in the regulation 
process, is required and the data which is required for an EUP 
application are major areas of concern by researchers and producers of 
pheromone pesticide products. A 1987 survey of companies actively 
involved in the registration of pheromones and companies that have 
considered and rejected pheromone development indicated that industry 
considered data requirements for pheromones to be excessive given the 
relatively safe nature of these substances, their extremely low rate of 
application, and their short persistence. Furthermore, it was noted 
that the applicant must incur the costs of developing most of the data 
to obtain an EUP, a stage in the product's development often too early 
to tell whether the pheromone is viable as a pesticide product. Given 
the limited earning potential of pheromone products, such testing costs 
tend to be prohibitively expensive; this is in addition to the high 
initial production costs of the pheromones themselves.
    Over the years, industry has suggested several changes in EPA rules 
and procedures to aid the development and ease the regulatory standards 
for pheromones and similar semiochemicals. The Agency is now at a point 
where it believes there is a sufficient body of information in the 
public literature and has adequate data available on arthropod 
pheromones, and is now taking steps toward this end.
    Today's notice announces a new agency policy of allowing pheromones 
in solid matrix dispensers to be tested on acreages not exceeding 250 
acres of land under the conditions specified in this notice without an 
EUP. This policy only applies to arthropod pheromones in solid matrix 
dispensers, as defined in this notice, applied at rates not to exceed 
150 grams AI/acre/year.
    Conditional relief consisting of exemption from regulation under 
FIFRA has previously been granted by EPA for pheromone traps in which 
the pheromones are the sole active ingredient(s) (See 40 CFR 
152.25(b)). In addition, EPA, on its own initiative, issued a proposed 
rule in the Federal Register of December 8, 1993 (58 FR 64538), which 
proposes to exempt from the requirement of a tolerance under the 
Federal Food, Drug, and Cosmetic Act (FFDCA) the residues of arthropod 
pheromones resulting from the use of these substances in solid matrix 
dispensers with an annual application rate limitation of 150 grams AI/
acre/year for pest control in or on all raw agricultural commodities. 
The scope of pheromone products exempted by this tolerance proposal 
would be the same as the scope of products subject to this notice. EPA 
currently is considering whether to take additional actions to grant 
further regulatory relief for other types of pheromone products. If EPA 
determines that any such regulatory relief is warranted, EPA would 
announce such a decision in a future Federal Register notice.

II. Statutory and Regulatory Authority

    Section 5 of FIFRA, 7 U.S.C. 136c and 40 CFR part 172 provide for 
issuance by the Agency of EUP's for the testing of new, unregistered, 
pesticides or registered pesticides being tested for new uses, in which 
the purpose is only to determine its value for pesticide purposes or to 
determine its toxicity or other properties. Such permits are generally 
issued for large-scale testing of pesticides on more than 10 acres. 
Contained within the scope of the regulation, however, is the 
presumption that small-scale testing, i.e., on not more than 10 acres 
of land, does not require an EUP provided that the crops are destroyed 
or an appropriate tolerance is in place (40 CFR 172.3(a)). This 
presumption, however, is caveated not to preclude experimental testing 
on larger areas in certain circumstances where the purpose of the large 
acreage test is only to determine the substance's value for pesticidal 
purposes or to determine its toxicity or other properties, and no 
benefit from pest control is expected (40 CFR 172.3(b)). EPA issued in 
the Federal Register of January 22, 1993 (58 FR 5878), a proposed 
amendment to 40 CFR part 172. The proposed amendment would, among other 
things, modify Sec. 172.3 to clarify that the determination of whether 
an EUP is required is based on risk considerations. The amendment would 
provide that tests conducted on not more than 10 acres of land are 
presumed not to involve unreasonable risks, and therefore, do not 
require an EUP.
    EPA believes that pheromone products in solid matrix dispensers 
must be tested at acreages larger than 10 acres and as large as 250 
acres to determine the products' value for pesticidal purposes. The 10 
acre presumption in 40 CFR 172.3(a) is appropriate for most substances, 
which can be tested to determine their value for pesticidal purposes at 
small acreages below 10 acres. Due to the unique characteristics of 
pheromones in solid matrix dispensers, however, these products must be 
tested at much larger acreages. Most pheromone uses involve mating 
disruption. Unlike traditional toxicants which usually focus on killing 
the immature insect (which often does the most damage), pheromones act 
upon the adult.
    Insects use pheromones to locate potential mates. When pheromones 
are introduced over an area by man as a pest control technique, the 
insects become confused by the seemingly ubiquitous presence of the 
guiding compound and therefore cannot find a suitable mate. When 
successful, pheromone applications result in reduced mating, lower 
insemination rates, and therefore lower population densities in the 
next generation. The evaluation of pheromones cannot be accomplished on 
small acreages because the treated area must be of sufficient size to 
account for the natural flight range of the target pests, such that 
already mated females flying into the test area do not skew the results 
of the study. This problem does not occur for most traditional toxicant 
pesticides which usually target the immature stage as these earlier 
life stages do not possess the capability of flight.
    An additional factor necessitating larger acreages is the volatile 
nature of most pheromone compounds. It is unfeasible to adequately 
separate treatments with small plots. For these reasons pheromones are 
usually tested in plot sizes ranging from 20 to 60 acres, depending 
upon the nature of the treated site and the pest in question. To 
provide scientifically sound information, it is generally conceded that 
four to six replications are necessary to validate the findings. Thus, 
the position that 250 acres should be sufficient to determine the value 
for pesticidal purposes of most pheromones. Moreover, as discussed in 
the section entitled ``Exposure and Effect,'' below, EPA believes that 
pheromones in solid matrix dispensers tested on no more than 250 acres 
and at maximum application rates of 150 grams AI/acre/year will not 
cause unreasonable adverse effects on the environment.

III. Exposure and Effect

    Since 1986, EPA has reviewed many arthropod-active pheromone 
products and has extensively reviewed pheromone toxicology data from 
the public literature. Based on this information, discussed more fully 
below, EPA believes that field tests conducted with pheromones in solid 
matrix dispensers and under the conditions outlined in this policy, 
will not cause unreasonable adverse effects on the environment. This 
conclusion is based on a number of factors, including the generally low 
toxicity and high volatility of pheromones, the low environmental and 
human exposure expected from pheromones used in solid matrix 
dispensers, and the low application rates and limited acreage required 
by this policy. Although the natural background level of pheromones in 
the atmosphere has never directly been determined, atmospheric levels 
for some pheromones have been estimated for peak population levels 
based on the pheromone emission rates for individual female arthropods. 
These estimated values range widely since they can be based on the 
amount of pheromone present in extracted glands or the measured 
emission rate and depend on what is considered the adult population 
during a peak pest infestation. To safeguard for the lack of data on 
natural background levels, EPA has determined to set an upper limit on 
the total amount of active ingredient released per acre per year from 
solid matrix dispensers at 150 gm. The upper limit rate is necessary to 
ensure that pheromones used in solid matrix dispensers do not result in 
increased levels of pheromones beyond natural background levels.
    The current upper limit for the application of a biochemical active 
ingredient lacking significant toxic effects that does not require the 
submission of residue data is 20 grams AI/acre (40 CFR 
158.690(b)(2)(B)). To facilitate testing of pheromones for pesticidal 
purposes, the Agency is setting a more realistic upper limit for the 
amount of active ingredient released during a season before an EUP is 
required. The Agency has found that given the low expected toxicity and 
high volatility of arthropod pheromones, an upper limit of 150 grams 
AI/acre/year is adequate for testing a pheromone product's feasibility 
and efficacy while still protecting public health, nontarget organisms 
and the environment from unreasonable risks from compound levels which 
may be above ambient natural productions. These application rates 
encompass the majority of pheromone uses seen by the Agency to date.

IV. Human Health

    The study results and submitted data available to date have 
indicated the following: acute oral toxicity - (LD50 > 5,000 mg/kg 
category IV (nontoxic)); acute dermal toxicity (LD50 > 2,000 mg/kg 
category IV, (nontoxic)), acute inhalation toxicity (LD50 
generally > 5 mg/L- category III-IV, practically (nontoxic)); no 
evidence of mutagenicity (Ames Salmonella assay); and minimal eye and 
skin irritation.
    EPA has reviewed the results of submitted mammalian toxicology 
studies for the pheromone products registered to date and also 
pheromone toxicology data from the public literature. The majority of 
the compounds registered to date (26 of 31) have been Lepidopteran 
(e.g. butterfly and moth) pheromones. These registered pheromones fall 
within a well defined class of chemical structures: aliphatic compounds 
with straight chains from 9 to 18 carbons in length and up to 3 double 
bonds, and ending in an acetate, alcohol, aldehyde functional group. 
Pheromones have been discovered with other chemical structures 
including compounds with ketone, epoxide, lactone, terpenoid, pyrazine, 
pyran, and aromatic structures. In 1983, when EPA promulgated the 
exemption for pheromones used in traps, the Agency did not distinguish 
between the rather restricted class of chemicals produced by 
Lepidopteran species and pheromones with different chemical structures 
produced by other arthropod species (e.g. beetles, flies, and mites) 
for use in traps. Because the proposed interpretation that the use of 
pheromones in solid matrix dispensers at an annual rate of up to 150 gm 
AI/acre represents the same human risk as the use of pheromones in 
traps, EPA does not believe there is a reason to distinguish between 
chemical classes of pheromones for pheromones in solid matrix 
dispensers.
    While the toxicology data base for pheromones with structures 
outside the well defined aliphatic Lepidopteran pheromones, such as 
aromatic compounds, is not as extensive, there is no indication of 
significant toxic effects to mammalian species from those compounds 
registered to date. The literature indicates that some aromatic 
pheromone compounds could be potentially toxic due to structural 
similarities to other aromatic compounds. The data available to date on 
both Lepidopteran and other arthropod pheromones, including several 
aromatic pheromones, however, have indicated no mammalian toxicity at 
the limit dose levels.
    The volatility of these compounds also predicts that little, if 
any, of the released compound will actually be associated with the 
crop. Studies to measure the natural background levels of insect 
pheromones in the environment or in or on fruit indicate little or no 
detectable residues. When pheromone residue analyses were done on fruit 
treated with from 129 to 141 gm AI/acre, no residues could be found 
with a detection limit of 2 to 5 ppb (Refs. 1 and 2). The current 
regulations provide that, in the absence of any significant toxic 
effects, residue analysis can be required when biochemical pesticides 
are applied above 20 gm AI/acre (40 CFR 158.690(b)). The Agency 
recognizes that the 150 gm AI/acre/yr rate is well above the 20 gm/acre 
limit triggering a food residue analysis. However, the negligible 
exposure for pheromones in dispensers, the natural occurrence of these 
compounds, their rapid biodegradation, high volatility and low worker 
exposure associated with solid matrix dispensers justify raising the 
limit for when an EUP is required for testing these volatile 
biochemical pesticides.
    Moreover, the Agency believes that an upper limit of 150 gm AI/
acre/year for pheromones labeled for use in dispensers as described 
below does not present a significant risk of dietary exposure due to 
the unlikelihood of direct contact with food and the low probability of 
deposition on food or feed following atmospheric dilution. EPA, on its 
own initiative, issued a proposed rule in the Federal Register of 
December 8, 1993 (58 FR 64538), which proposes to exempt from the 
requirement of a tolerance under the Federal Food, Drug, and Cosmetic 
Act (FFDCA) the residues of arthropod pheromones resulting from the use 
of these substances in solid matrix dispensers with an annual 
application rate limitation of 150 grams AI/acre/year for pest control 
in or on all raw agricultural commodities. However, until this 
exemption from the requirements of a tolerance becomes a final rule 
(anticipated in February 1994), a temporary tolerance and EUP 
application will be required if the treated crop enters channels of 
trade. A final rule establishing an exemption from the requirements of 
a tolerance for inert ingredients of retrievably sized semiochemical 
dispensers composed of polymeric matrix materials was published in the 
Federal Register of December 8, 1993 (58 FR 64493).

V. Ecological Effects

    Wildlife toxicity data indicate: high toxicity to aquatic 
invertebrates and moderate toxicity to fish, but practically no 
toxicity to birds tested. Data for one Lepidopteran pheromone indicate 
low toxicity to avian bobwhite quail (acute oral LD50 of >2,000 
mg/kg of body weight and dietary LC50 of >5,000 mg/kg). However, 
this pheromone had a freshwater aquatic invertebrate (Daphnia magna) 
LC50 of between the solubility limit of 0.2 mg/l and a calculated 
LC50 of 0.58 mg/l. Observations of oily surface films at higher 
test concentrations confirmed the low solubility of the test material. 
The conclusion was that this pheromone was highly toxic to Daphnia and 
that the calculated LC50 supported this conclusion. Whether the 
mortality was due to the pheromone in solution or a film on the water 
was not determined. Another Lepidopteran pheromone was found to be 
moderately toxic to both Daphnia magna (LC50 8.6 mg/l) and the 
freshwater rainbow trout (LC50 5.9 mg/l). These results are 
sufficient to demonstrate the potential toxicity of Lepidopteran 
pheromones to nontarget aquatic organisms.
    Although pheromones may be in matrix dispensers, rates of 
dissociation from matrices into water are not known. Refined petroleum 
oils which form films at the water surface are registered by the Agency 
as pesticides for control of mosquito larvae and pupae. Pesticidal 
oils, which may comprise some of these products, kill by arresting 
invertebrate respiration and affect interfacial tension at the water 
surface upon which various arthropods depend for functions including 
feeding, movement, and reproduction. To minimize the potential toxic 
effects on aquatic organisms, the pheromone formulations in solid 
polymeric matrix retrievably sized dispensers should be for terrestrial 
use only and the experimental use should not include use in or around 
marshes, swamps, rivers, streams, ponds, lakes, estuaries, flood 
plains, or drainage ditches. They should not be allowed to wash or 
drain into water.
    Despite the toxicity to aquatic organisms from pheromones, EPA 
believes that risks to aquatic organisms for tests conducted under the 
conditions outlined in this notice are low. Pheromones in solid matrix 
dispensers would not be expected to be used in water. In addition, many 
of the solid matrix dispensers of the type covered by this policy are 
typically affixed to trees or plants or other fixed objects, and thus, 
are not likely to end up in bodies of water.
    Broadcast application is not included in this notice because the 
Agency does not have sufficient information on the levels of exposure 
from pheromones which are broadcast.

VI. Solid Matrix Dispensers

    Solid matrix dispensers, as defined in this notice, include, but 
are not limited to: Rubber septa dispensers, trilaminate sheets, tapes, 
tags, wafers, macrocapillary devices, such as long tubes or fibers, 
twist ties, or ropes which are placed by hand in the field and are of 
such and construction that they are readily seen. This policy does not 
apply to the following formulations: Liquid flowables, microcapsules, 
microcapillary straws, granular powder, flakes, or confetti 
formulations which are sprayed or broadcast over an area; and cigarette 
filters or unprotected ropes which generally contain the active 
ingredient on the outer surface of the unit. The dispensers must not be 
of a size, odor, taste or have other characteristics making them 
attractive to wildlife that potentially could collect or eat them. 
Devices like netting, webbing, loose filaments, and adhesives capable 
of trapping or ensnaring nontarget organisms such as birds also would 
not be covered by this policy. If inadvertently eaten, these dispensers 
should be nontoxic and readily pass through an animal digestive system 
without causing blockage or puncture.

VII. Agency Determinations

    EPA has determined, pursuant to 40 CFR 172.3, to expand the land 
use limitation for testing for pesticidal value without the need for an 
EUP from 10 acres to 250 acres for arthropod pheromones in solid matrix 
dispensers using no more than 150 grams AI/acre/year. This 
determination is based both on a finding that tests conducted under the 
conditions outlined will not cause unreasonable adverse effects on the 
environment and on EPA's belief that it is necessary to test pheromones 
in solid matrix dispensers on large acreages (i.e., larger than 10 
acres) to determine their value for pesticidal purposes. EPA retains 
the authority under 40 CFR 172.3 to require EUP's, on a case-by-case 
basis, for tests conducted on acreages smaller than 250 acres if EPA 
determines that the test is not being conducted only for the purpose of 
determining the pheromone's value for pesticidal purposes or if EPA 
determines that the test may cause unreasonable adverse effects on the 
environment in the absence of agency oversight in the form of an EUP.
    Today's notice only addresses EPA's policy with regard to EUP's for 
pheromones in solid matrix dispensers. This notice does not in any way 
obviate the need to obtain a tolerance under the FFDCA before using a 
pheromone product for food or feed use. EPA intends to address use of 
pheromones in solid matrix dispensers on food or feed crops with an 
exemption from the requirement for a tolerance under FFDCA. Such a 
proposed exemption was published in the Federal Register of December 8, 
1993 (58 FR 64538). Moreover, EPA has published a final rule exempting 
certain inert ingredients used in solid matrix dispensers from the 
requirement of tolerance (December 8, 1993, 58 FR 64493).
    Today's notice in no way affects the need to obtain an EUP for 
tests conducted on more than 10 acres with formulations of pheromones 
products other than those described in the notice (i.e., pheromone 
formulations which are physically smaller than solid matrix dispensers, 
such as sprayables). EUP's will continue to be required for tests 
conducted on more than 10 acres using non-solid matrix dispenser 
formulations.
    EPA currently is considering whether to take additional actions to 
grant further regulatory relief for other types of pheromone products. 
If EPA determines that any such regulatory relief is warranted, EPA 
would announce such a decision in a future Federal Register notice.

VIII. References

    (1) Spittler, T. D.; Leichtweis, H. C.; Dennehy, T. J. (1988). 
Biorational Control of Crop Pest by Mating Disruption; Residue Analyses 
of Z-9-Dodecen-1-yl Acetate and Z-11-Tetradecenyl-1-yl Acetate in 
Grapes. In: Biotechnology for Crop Protection, P. Hedin, J. J. Menn and 
R. Hollingworth (eds.) ACS Symposium Series, 379:430-436.
    (2) Spittler, T. D., Leichtweis, H. C., Kirsch, P. (1992). 
Exposure, Fate and Potential Residues in Food of Applied Lepidopteran 
Pheromones. In: Insect Pheromones and Other Behaviour-Modifying 
Chemicals: Application and Regulation, R. L. Ridgeway, M. Inscoe and H. 
Arn (eds.), BCPC Monograph No. 51, pp. 93-108.

    Dated: January 19, 1994.
Stephanie R. Irene,
Acting Director, Registration Division, Office of Pesticide Programs.
[FR Doc. 94-1615 Filed 1-25-94; 8:45 am]
BILLING CODE 6560-50-F