Framework for Addressing Key Science Issues Presented by the Food
Quality Protection Act (FQPA) as Developed Through the Tolerance
Reassessment Advisory Committee (TRAC)
[Federal Register: October 29, 1998 (Volume 63, Number 209)]
[Notices]
[Page 58038-58045]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29oc98-70]
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ENVIRONMENTAL PROTECTION AGENCY
[OPP-00557; FRL-6041-5]
Framework for Addressing Key Science Issues Presented by the Food
Quality Protection Act (FQPA) as Developed Through the Tolerance
Reassessment Advisory Committee (TRAC)
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice.
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SUMMARY: The notice announces a schedule and framework for EPA issuance
of a series of science policies to implement provisions in the Food
Quality Protection Act of 1996 (FQPA). The notice and comment approach
described in this notice was created following discussion with the
Tolerance Reassessment Advisory Committee (TRAC), a subcommittee of the
National Advisory Council on Environmental Policy and Technology
(NACEPT), a committee established pursuant to the Federal Advisory
Committee Act. Comments on individual interim science policy documents
will be invited through separate notices in the Federal Register as
outlined in the framework. While refining its approach to FQPA science
policies, EPA will use the policies described in the interim documents
when making decisions on pesticide actions.
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 VII. 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: Jeff Kempter, Registration Division
(7505C), Office of Pesticide Programs, Environmental Protection Agency,
401 M St., SW., Washington, DC 20460. Office location, telephone
number, and e-mail address: Rm. 713D, CM #2, 1921 Jefferson Davis
Highway, Arlington, VA; (703) 305-5448; kempter.carlton@epa.gov.
SUPPLEMENTARY INFORMATION: The following documents are available from
the EPA Home page at the Federal Register - Environmental Documents
entry for this document under ``Laws and Regulations'' (http://
www.epa.gov/fedrgstr/):
1. This document.
2. A table entitled ``Framework for Refining FQPA Science Policy.''
3. A timeline entitled ``Schedule for Release of Guidance on
Science Policy Issues.''
Copies of the above-mentioned table and timeline may also be
obtained from the OPP docket at the location listed under ADDRESSES or
by contacting Jeff Kempter at the telephone number listed above.
I. Background
A. Food Quality Protection Act (FQPA)
On August 3, 1996, the Food Quality Protection Act of 1996 (FQPA)
was signed into law. Effective upon signature, FQPA significantly
amended the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)
and the Federal Food, Drug, and Cosmetic Act (FFDCA). Among other
changes, FQPA established a stringent health-based standard (``a
reasonable certainty of no harm'') for pesticide residues in foods to
assure protection from unacceptable pesticide exposure; provided
heightened health protections for infants and children from pesticide
risks; required expedited review of new, safer pesticides; created
incentives for the development and maintenance of effective crop
protection tools for farmers; required reassessment of existing
tolerances over a 10-year period; and required periodic re-evaluation
of pesticide registrations and tolerances to ensure that data
supporting pesticide registrations will remain up-to-date in the
future.
B. Food Safety Advisory Committee (FSAC)
When FQPA took effect, EPA was immediately faced with having to
implement new standards and requirements. The Agency established the
FSAC as a subcommittee of the NACEPT to assist in soliciting input from
stakeholders and to provide input to EPA on some of the broad policy
choices facing the Agency and on strategic direction for the Office of
Pesticide Programs (OPP). With the guidance and input of the FSAC, the
Agency issued several key documents concerning how it would implement
FQPA: (1) On January 31, 1997, Pesticide Registration Notice 97-1
entitled ``Agency Actions Under the Requirements of the Food Quality
Protection Act'' provided an interim decision logic for making
regulatory decisions; (2) the ``1996 Implementation Plan,'' made
available in March 1997, described EPA's overall plan for implementing
the requirements of FQPA; and (3) on August 4, 1997, a Federal Register
notice entitled ``Raw and Processed Food Schedule for Pesticide
Tolerance Reassessment'' announced a specific plan for conducting
reassessments of tolerances in effect as of the passage of FQPA.
The Agency has used the interim approaches developed through
discussions with FSAC to make regulatory decisions that met FQPA's
standard and that could be revisited if additional information became
available or as the science evolved. As EPA's approach to implementing
the scientific provisions of FQPA has evolved, the Agency has sought
independent review and public participation, often through presentation
of many of the science policy issues to the FIFRA Scientific Advisory
Panel (SAP), a group of independent, outside experts who provide peer
review and scientific advice to OPP.
C. Tolerance Reassessment Advisory Committee (TRAC)
Although the Agency has sought independent review and public
participation on a wide variety of issues, the Agency has decided that
the implementation process would benefit from a more thorough process
of notice and comment on major science policy issues. As directed by
Vice President Albert Gore, EPA has been working with the U.S.
Department of Agriculture (USDA) and a new subcommittee of
[[Page 58039]]
NACEPT, the TRAC, chaired by the EPA Deputy Administrator and the USDA
Deputy Secretary, to address FQPA issues and implementation. TRAC
comprises more than 50 representatives of affected user, producer,
consumer, public health, environmental, states, and other interested
groups. The TRAC has met five times as a full committee from May 27
through September 16, 1998.
The Agency has been working with TRAC to ensure that its science
policies, risk assessments of individual pesticides, and process for
decision making are transparent and open to public participation. An
important product of these consultations with TRAC is the development
of a framework document for addressing key science policy issues. This
Federal Register notice is based on, but not identical to, the EPA
staff paper #26 which is the draft framework document presented to the
TRAC that identified the issues relating to these science policy
issues.
The TRAC identified nine science policy issues it believed were key
to the implementation of FQPA and tolerance reassessment. The framework
calls for EPA to provide one or more documents for public comment on
each of the nine issues over the course of the next several months. EPA
will issue Federal Register notices announcing the availability of each
of these science policy documents for comment. Other opportunities for
public involvement in the refinement of these policies may also be
available, depending on the current status of the individual science
policy. Each of these issues is evolving and in a different stage of
refinement. Accordingly, as the issues are further refined by EPA in
consultation with USDA and others, they may also be presented to the
SAP. This notice describing the framework briefly summarizes each of
the nine science policy issues, the efforts underway to refine them,
plans for notice and comment, and the timelines for completing
refinements.
II. The Nine Science Policies
A. Science Policy 1: Applying the FQPA 10-Fold Factor
FQPA requires EPA to use an additional 10-fold factor when
assessing a pesticide's dietary risk to take into account potential
pre- and post-natal developmental toxicity and completeness of the data
with respect to exposure and toxicity to infants and children. The
additional FQPA factor may be reduced or removed only if, on the basis
of reliable data, the factor used will be safe for children. (It should
be noted that, under certain circumstances, the Agency may use a higher
factor than the traditional 100-fold uncertainty factor, for example,
because of a limited toxicity data base.) In assessing risk, the Office
of Pesticide Programs (OPP) applies the 10-fold factor unless it
determines, based on a weight-of-the-evidence evaluation of all
reliable, available information on toxicity and exposure, that it
should be modified.
The major science policy issue related to the 10-fold FQPA factor
is the establishment of appropriate, clear, and transparent criteria
for retaining or modifying the 10-fold factor. Another closely related
issue is determining what constitutes a complete and reliable data base
for toxicology and exposure data to assess risks to children.
In part, to address these issues, an intra-agency workgroup is
looking at general considerations regarding the FQPA factor decisions
such as: establishing procedures for consistency and documentation;
ensuring the adequacy of the data set for decision-making; and
establishing criteria for retaining or modifying the FQPA factor. This
workgroup includes representatives of the Office of Research and
Development, the Office of Children's Health Protection, the Office of
Water, the Office of Solid Waste and Emergency Response, as well as the
Office of Prevention, Pesticides and Toxic Substances. In addition, OPP
has completed a draft Standard Operating Procedure (SOP) that provides
procedural guidance at the working level for making recommendations for
retaining or modifying the 10-fold factor.
In addition, EPA has solicited advice from the SAP. In October
1996, EPA first brought to the SAP a paper that described a ``weight-
of-evidence'' approach for the 10x FQPA factor, that was developed
prior to the passage of FQPA. In March 1998, the Agency brought OPP
Health and Effects Division (HED) draft guidance on the application of
the FQPA factor to the Panel. In July 1998, EPA updated the SAP on its
progress in responding to their comments.
The Intra-Agency workgroup draft guidance document will be
completed and available for comment in January 1999. At that time, EPA
will publish a notice of availability and a 60-day opportunity to
comment on the guidance document. A revised document will be ready no
later than June 1999. The draft working level document (the SOP) is
complete; it will be issued with the Intra-Agency document in February
1999, for comment and will be revised in light of public comment by
July 1999.
B. Science Policy 2: Dietary Exposure Assessment - Whether and How to
Use ``Monte Carlo'' Analyses
EPA assesses dietary exposure to pesticides in raw and processed
foods using two distinct pieces of information: the amount of pesticide
residue that is present in and on food (i.e., the residue level) and
the types and amounts of food that we eat (i.e., food consumption). The
residue information comes from the numerous crop field trials and other
sources (such as monitoring data) where the amount of pesticide residue
on a given commodity is measured. Routinely, consumption information
comes from USDA surveys of what people eat. In the past, EPA has used
the Dietary Risk Evaluation System (DRES) which is a deterministic
model to combine the residue and food consumption information with data
on a pesticide's toxicity to calculate acute and chronic dietary risk.
This deterministic model calculates a single value (sometimes referred
to as a point estimate) for all the residues for a given commodity.
Over the last few years, a different technique has been applied to
estimating acute dietary exposure--a probabilistic evaluation called
Monte Carlo analysis. A probabilistic analysis uses the entire range of
data from the numerous crop field trial studies, or other sources to
estimate the distribution of exposure to the residues for the
population of concern. This technique allows for a more realistic
estimate of exposure.
There are three issues associated with the use of probabilistic
techniques:
1. Probabilistic analyses often exhibit a level of uncertainty at
the extremes of the distribution. This uncertainty makes it difficult
to judge if the results reflect an accurate estimate of risk, or an
overestimate or underestimate risk.
2. EPA needs to make decisions that are appropriately protective of
larger numbers of people, especially children, necessitating estimates
of ``high end'' exposures (e.g., 99.9th percentile).
3. There is a concern over statistical treatment of data that are
inputted into the Monte Carlo model. For example, how USDA's high end
consumption estimates combine with the use of a 99.9th percentile
output needs to be resolved.
The following steps have been taken or are being taken to address
these issues:
1. In March 1998, the Agency presented to the SAP for comment draft
[[Page 58040]]
guidance for submission of probabilistic exposure assessments.
2. USDA and EPA are jointly assessing how best to treat data
representing the extremes of exposure.
3. The issue of the appropriateness of using the 99.9th percentile
was presented to the SAP. SAP comments are being considered.
4. EPA is drafting a policy paper on use of the 99.9th percentile
in decision-making.
5. The Agency is working on statistical methods for effectively
using composite data to estimate exposure from single-serving-sized
food items.
These products will result:
1. SAP comments will be considered when preparing the next
iteration of the draft document entitled ``Guidance for Submission of
Probabilistic Exposure Assessments to the Office of Pesticide Programs'
Health Effects Division.'' The document will be issued in October 1998
for a 60-day comment period. Revised guidance will be issued no later
than March 1999.
2. In addition, USDA is reviewing its existing (1989-1991) food
consumption data to ensure accuracy. This process will be completed in
October 1998.
3. The policy paper exploring probabilistic techniques and the
99.9th percentile (draft working title ``Monte Carlo Techniques and the
99.9th Percentile'') will be issued for a 60-day comment period in
December 1998. A revised document will be available no later than May
1999.
4. Finally, the draft paper on statistical methods on using
composite data to estimate exposure from single serving food items
(draft working title ``Use of the Pesticide Data Program in Acute
Dietary Assessment'') will be issued for a 60-day public comment period
in April 1999. The Agency will issue a revised document no later than
September 1999.
C. Science Policy 3: Exposure Assessment - Interpreting ``No Residues
Detected''
Pesticide manufacturers (i.e., registrants) seeking to have a
tolerance established are required to submit data on the level of
pesticide residues that remain in or on food. Often, instrumentation in
the laboratory is not able to detect any residue below a specified
level, which is called the ``limit of detection'' or LOD. However, even
though the laboratory instrumentation cannot detect a residue, a
residue may be present, at some level below the LOD, which may still
present a potential concern to human health. Current EPA policy is to
assume that non-detectable residues remain on treated commodities at
\1/2\ LOD.
How the Agency should interpret non-detects and how they should be
incorporated into risk assessments presents these issues:
1. The Agency's method for incorporating non-detectable residues
into its risk assessment (\1/2\ LOD) may either overestimate or
underestimate risk depending on the actual distribution of data below
the LOD.
2. There are potential trade and public health impacts if the
Agency cancels a use, and subsequently revokes the corresponding
tolerance in the U.S., based upon apparent unacceptable risks
attributable in significant part to non-detectable residues, while
other countries allow that use. If risks were accurately assessed or
were underestimated, crops posing unacceptable risks may be imported
into the U.S. because residues cannot be detected. If risks were
overestimated, U.S. pesticide users may unnecessarily lose tools
available to foreign growers.
EPA, FDA, and USDA are working together to develop and validate
improved analytic chemistry methods for detecting residues of
organophosphate pesticides. These improved methods are expected to be
adapted to routine surveillance monitoring programs and to provide
greater sensitivity than currently used methods. The use of more
sensitive analytical methods should lessen the chance that imported
food commodities may be treated with pesticides whose use is not
allowed in the United States. In short, new, more sensitive methods
should help to establish a ``level playing field'' for domestic growers
and better protect U.S. consumers.
FQPA requirements to combine exposures from all sources (e.g.,
food, drinking water, and residential exposure) and from all chemicals
with a common mechanism of toxicity magnify this problem. The resulting
risk estimates may be significant even when a substantial portion of
residues are below the level of detection.
The Agency has two initiatives underway to address the above
issues:
1. An EPA workgroup is examining approaches that could allow EPA to
determine that there is ``no reasonable expectation of finite
residues.'' With sufficient data and clearer guidelines, uses for which
food residues are truly insignificant could be demonstrated to have
practically no dietary risk associated with them. This change would
allow the Agency to focus its resources on evaluating exposures to
pesticides at levels below the LOD, for which there is potential risk
of concern. This change would also improve international harmonization.
A paper entitled ``Threshold of Regulation'' will be issued in November
1998 for a 60-day comment period and will be revised in light of public
comment no later than April 1999.
2. An OPP group is examining the availability of better statistical
methods for assessing data sets that contain both detectable and
nondetectable residues. Two papers will be issued as a result of this
effort and will describe EPA's approaches to lessen the likelihood that
the Agency's assessments either overestimate or underestimate food-
borne exposure. The first paper (draft working title ``Use of Censored
Data in Risk Assessments'') describes how to use statistical methods
for situations where some of the residues are undetectable. The second
paper (draft working title ``ChemSAC decision regarding use of LOD vs.
LOQ (Limit of Quantitation) in dietary exposure assessments'')
describes the use of limit of detection versus limit of quantitation in
dietary exposure assessment. Both of these papers will be released for
a 60-day public comment period in November 1998, with revised guidance
to be issued no later than April 1999.
D. Science Policy 4: Dietary (Food) Exposure Estimates
In assessing dietary exposure from pesticide residues in food, EPA
starts out with the ``worst-case'' residue level, which is the
tolerance. Tolerances are regulatory levels and are set to accommodate
the highest residue level that may be found in crops at the farm gate.
Crop field trials are used to determine the highest residue level that
can result from maximum legal use of a pesticide. As discussed below,
actual residues on food are much lower, and may be virtually non-
existent. Assuming that residues are present at tolerance level and
that 100% of the crop is treated allows rapid cost-effective decision-
making in many cases where risks are low. In these cases, there may be
no need for registrants to collect additional data or for the Agency to
use resources to review additional data.
Food exposure assessments can be improved with information on
actual pesticide use, agricultural practices, processing practices, and
actual or anticipated residues. This type of information includes data
on pre-harvest intervals, actual application rates, application
frequency, percent of the crop that is treated, pesticide degradation
between harvest and the time the crop reaches the consumer (degradation
over time), cooking and commercial processing studies, and
[[Page 58041]]
other related information, such as more comprehensive monitoring data
for food and water. To estimate anticipated residue levels, the Agency
may also need certain supporting residue data, such as residue decline
studies, or procedures to translate or model residue data for typical
use practices.
USDA provides the Agency with extensive information on pesticide
use, food consumption data, and pesticide residues. The USDA
information and information from other sources are key to the
preparation of more realistic exposure assessments which then lead to
more realistic acute and chronic dietary risk assessments. USDA and EPA
work to ensure that the needed information is identified, collected,
and used appropriately in the risk assessment. USDA and EPA have and
will continue to obtain use information from growers which is then
reviewed by the Agency and the registrants. EPA then identifies data
gaps or the need for supplemental information.
The Agency has been working to complete the National Pesticide
Residue Database (NPRD), a comprehensive database that will contain
information about actual pesticide residues in raw and processed foods.
A complete version of the NPRD is expected in November 1998, and will
be available on EPA's web page. EPA will provide a description on the
history, development, and use of NPRD; this will be available in
December 1998.
There are several issues associated with the need for data to
estimate food exposure more realistically:
1. Dietary risk estimates may be unrealistically high when typical
use practices have not been factored in.
2. Information on actual pesticide use may be available, but
residue levels resulting from such use cannot be calculated without
certain residue testing, modeling efforts, or bridging data to meld the
guideline studies with actual usage information.
3. Monitoring data are not available for all commodities, resulting
in use of significantly different data in risk assessments for
different chemicals and/or foods, and high risk estimates for those
pesticides and crops that lack monitoring data.
To address the issues discussed above, the following products are
forthcoming:
1. EPA will issue for comment in December 1998 a draft overview
document (draft working title ``Framework for Dietary (Food) Exposure
Assessment'') that describes how OPP does acute and chronic food
exposure assessments and, more importantly, where in the existing
guidance one can find methods for doing such exposure assessments; it
will also provide guidance for growers, states, and others when
collecting use information to explain the need for certain residue
information (a revised document will be issued no later than April
1999).
2. EPA will complete matrices describing organophosphate use and
usage on individual crops by December 1998. These matrices present
real-world information on pesticide usage and the pests which drive the
usage, and are developed with support from USDA and the grower
community.
High quality consumption data are also critical to developing more
accurate risk assessments. EPA recently acquired the capability to
perform acute dietary risk assessments using state-of-the-art software
and the most recently available USDA food consumption data (1989-91).
In addition, USDA, in cooperation with EPA, is translating the most
recently conducted food consumption survey information (1994-96) into a
data format that can be used in EPA's risk assessments (i.e., from
foods as eaten to the raw agricultural commodities which make up those
foods). A peer review of the assumptions or ``recipes'' used in the
translation of this consumption data will be held in April 1999. The
final translation should be completed and available to EPA no later
than June 1999. In addition, USDA is currently completing collection of
supplementary food consumption data for children under the age of nine
years to improve the precision of the dietary risk estimates. These
data are being collected in such a manner that they will be combinable
with the 1994-96 data. The translated form of the supplemental
children's survey should be available to EPA no later than December
1999.
E. Science Policy 5: Dietary (Drinking Water) Exposure Estimates
For tolerance decisions under FQPA, EPA must now aggregate
exposures to a pesticide from both dietary sources (food and drinking
water) and all non-occupational sources for which there is reliable
information. There are two complementary methods for estimating
concentrations of pesticides in drinking water. The first is to measure
pesticide residues in drinking water by taking samples of drinking
water in use areas at appropriate times, especially during the use
season for surface water supplies. The second is to develop and use
mathematical models to predict pesticide levels in drinking water.
The Pesticide Program's currently available model-based approaches
for predicting potential drinking water exposure are based on screening
models that predict pesticide levels in vulnerable groundwater and
surface water. These predictions are generally believed to overestimate
the concentration of pesticides in most drinking water sources, and
hence, in some cases drinking water exposure may appear to present an
unacceptable dietary risk even though actual risks to most people may
in fact be lower.
Several efforts are underway to address the problem that current
screening models, particularly surface water screening models, do not
well represent drinking water systems and may significantly
overestimate residue levels in most drinking water sources. First, OPP
developed and presented to the FIFRA SAP in July 1998 a proposed
``reservoir scenario'' model as a replacement for the ``small field
pond'' model that is currently used to produce screening level
estimates of pesticide concentrations in drinking water derived from
surface water. By replacing the ``small field pond'' model with an
actual reservoir, EPA expects that its screening level drinking water
estimates for surface water will be more accurate. Subsequent to the
SAP presentation, OPP developed a list of about 20 possible reservoirs
that it may further evaluate for use as an index reservoir in its
screening level assessments. This list is currently available in the
public docket for this notice.
Second, OPP is working to develop the necessary data bases and
Geographical Information System-based tools to enable it to consider
the percentage of the area around a reservoir that is cropped and,
thus, potentially treated with a pesticide when it uses its model to
predict pesticide levels in a drinking water reservoir. Currently, OPP
assumes that the entire area surrounding a body of water is planted
with the crop and treated; this generally results in an overestimate of
the amount of pesticide leaving the field and running off into surface
water, and, therefore, an overestimate of pesticide concentrations in
surface water used as drinking water.
Third, OPP completed and presented to the FIFRA SAP in July 1998,
its preliminary evaluation of watershed-scale surface water models.
Further efforts are ongoing to conduct preliminary model validation of
the basin-scale models for the White River watershed in Indiana. This
model validation effort is expected to provide some preliminary
understanding of the relative accuracy of each of these models. OPP
expects that these basin-scale models will ultimately be used to
produce more refined estimates of
[[Page 58042]]
pesticide concentrations in drinking water for those cases where an
unreasonable risk is estimated by the use of a screening level
estimate.
In addition to the efforts described above, EPA has entered into a
cooperative agreement with the International Life Sciences Institute
(ILSI) to advance probabilistic drinking water exposure assessment
methodology. ILSI is working to independently develop long-term
recommendations for model development and data collection so that
estimates of pesticide concentrations in drinking water can be used in
probabilistic aggregate exposure analyses in the future. In September
1998, ILSI convened a panel of over a dozen scientists to consider such
issues as: (1) What drinking water related data are necessary to use in
probabilistic aggregate risk analyses and how can these data be
collected; and (2) what role modeling can play in generating
information/estimates on pesticide concentration distributions in
drinking water sources. Recommendations from the September 1998 meeting
will then be used in a follow-up meeting in December 1998, to develop
detailed recommendations on how to collect information that can be used
in probabilistic aggregate exposure analysis. ILSI expects to finalize
its recommendations in early 1999.
Finally, OPP continues efforts to gather and interpret available
drinking water monitoring data and to obtain additional monitoring of
pesticides in drinking water as individual registration and
reregistration decisions are made. Further, OPP is working with Federal
government-sponsored water monitoring programs such as the United
States Geological Survey's National Ambient Water Quality Assessment
Program to ensure that key pesticides and drinking water source waters
are covered; OPP is coordinating pesticide monitoring needs with EPA's
Office of Water and the states as well.
EPA is currently using interim policy and interim operating
procedures to factor drinking water exposure into tolerance decision-
making. EPA will continue to update its interim policy and interim
operating procedures as important new information becomes available.
Over the next 12 months, OPP expects to see three products
completed. First, the Agency will address the July 1998 SAP comments on
replacing the ``small field pond'' scenario with the reservoir scenario
and revise its operating policy to include the reservoir scenario in
screening level assessments. In its revision to its operating policy,
OPP expects also to propose a change in the Drinking Water Level of
Concern (DWLOC) terminology. This revised policy will be made available
for a 60-day comment period in December 1998, and will be revised in
light of public comment no later than May 1999. EPA expects to solicit
comment on the concept of replacing the ``small field pond'' scenario
with a specific type and size of reservoir, as well as on the timing
for implementation.
Second, the Agency will complete development of an approach to
factoring the percentage of land surrounding a reservoir that is
``cropped'' into its screening level assessments and revise its
operating policy to include this approach. The Agency plans to present
to the SAP in February 1999, a specific methodology for developing
cropped area factors, proposed cropped area factors for 5-10 major
crops and 5-10 minor crops, and examples of how cropped area factors
would be applied in screening level drinking water assessments. EPA
expects to resolve any issues raised by the SAP and expects to make
this revised policy available for a 60-day public comment period by May
1999. After consideration of public comments, a revised policy issue
paper will be issued no later than October 1999.
Third, the current HED SOP for factoring drinking water exposure
into dietary risk assessments will be updated in June 1999, to include
the reservoir scenario and will be published for a 60-day comment
period. EPA expects that the new SOP which incorporates the reservoir
scenario will be completed no later than November 1999. A revised SOP
that includes the percent cropped area treated will be made available
in December 1999, for comment and will be revised in light of public
comment no later than May 2000. The SOP will be periodically updated
thereafter as needed.
F. Science Policy 6: Assessing Residential Exposure
EPA must now include residential and other non-occupational
exposures in the aggregate exposure assessments for pesticides.
Generally speaking, residential exposure monitoring data have not been
routinely required. Thus, EPA has been relying on existing monitoring,
survey, and modeling data, including information on activity patterns,
particularly for children, to estimate residential exposure to
pesticides.
Because highly specific residential exposure data are generally
lacking and there is not wide understanding and acceptance of existing
models and assumptions, several workgroups and task forces are working
to generate data and improve methods for conducting residential
exposure assessments. Proposed Agency SOPs, which provide standard
methods for developing residential exposure assessments when data are
limited, were drafted and taken to the SAP for comment in November
1997. They are being revised based on the SAP comments and new
information from the published literature and other sources.
Additionally, the Indoor Residential Exposure Joint Venture, an
industry/Agency task force, is developing information on indoor
pesticide treatments and pet uses. In Phase I, the Joint Venture will
provide information to better characterize pesticide use patterns and
practices. In Phase II, it will apply these data to exposure
assessments, including, for example, looking at transferable residue
data from treated surfaces. The Task Force is generating these data to
support a consortium of registrant products; that is, these chemical-
specific data will be used in conjunction with or in lieu of the SOPs
(where deemed appropriate). Also, the Outdoor Residential Exposure Task
Force, another industry/Agency taskforce, is in the midst of generating
lawn and turf data to assess pesticide exposure from mixing, loading,
and applying pesticides, as well as exposure to people who enter a
recently treated turf area.
The Agency plans to incorporate the 1997 SAP comments on the SOPs
by December 1998. The revised SOPs will then be published with a 60-day
comment period. Revised documents will be completed no later than May
1999. On the same schedule, EPA plans to draft an overview document
(draft working title ``Framework for Residential/Public Area Exposure
Assessment'') on how it proposes to develop and use exposure estimates
for pesticides applied around residences and public areas. In addition,
the Indoor Residential Joint Venture Task Force is expected to have a
Phase 1 draft document available in March 1999; Phase 2 will be
completed by October 2000. Preliminary results from the Outdoor
Residential Exposure Task Force are expected in August 1999. The Agency
will review these chemical-specific data and information developed by
the Task Forces and use this information in conjunction with or in
place of the current SOPs, as appropriate.
[[Page 58043]]
G. Science Policy 7: Aggregating Exposures from all Non-Occupational
Sources
As noted in sections E. and F. of this unit, under the requirements
of FQPA, in setting tolerances EPA must now aggregate exposures from
all sources where there is available information. Methods for
aggregating exposures are being developed.
The current method for aggregating exposures using simple addition
provides only point estimates. Methods that more clearly demonstrate
the range of risks across the general population and population
subgroups would better characterize risk for risk management decisions
regarding pesticide use. These methods generally use probabilistic
analyses.
In addition to Agency efforts to address these issues, the
scientific community is examining comprehensive aggregate exposure
assessment approaches. In February 1998, ILSI conducted a public
workshop where three groups of experts presented their proposed
approaches. Workshop participants evaluated and commented on the
approaches.
ILSI will issue an independent scientific assessment of the
technical issues surrounding aggregation of distributions. This report
is scheduled to be completed in November 1998. After evaluation of this
report, along with other comments by the scientific community, the
Agency will develop a draft guidance document in April 1999 for a 60-
day comment period. A revised version in light of public comment should
be available no later than September 1999. In addition, EPA is
developing a Standard Operating Procedure paper which will follow the
same time line.
H. Science Policy 8: How to Conduct a Cumulative Risk Assessment for
Organophosphate Insecticides or Other Pesticides With a Common
Mechanism of Toxicity
Under FQPA, EPA is required to consider available information on
the effects of cumulative exposure to the pesticide and other
substances with common mechanisms of toxicity. EPA believes that the
organophosphate insecticides, the first group examined for tolerance
reassessment, should be considered to operate via at least one common
mechanism of toxicity-cholinesterase inhibition, unless and until the
Agency receives data demonstrating otherwise.
In the Federal Register of August 6, 1998 (63 FR 42031) (FRL-5797-
9), EPA issued a notice announcing the availability of the proposed EPA
pesticide policy guidance document entitled ``Guidance for Identifying
Pesticide Chemicals That Have a Common Mechanism of Toxicity for Use in
Assessing the Cumulative Toxic Effects of Pesticides.'' The guidance
document describes the approach that EPA proposes to use for
identifying and categorizing pesticide chemicals that have common
mechanisms of toxicity for purposes of assessing the cumulative toxic
effects of such pesticides. There is a 60-day comment period for this
document that ends in October 1998. Revised guidance will be issued no
later than January 1999. In developing this document, the Agency
solicited advice from the SAP in February 1997; a year later (March
1998), OPP reported its progress to the SAP.
Since there are currently no standard methods for doing cumulative
risk assessment, EPA is pursuing an open, peer-reviewed process to
develop approaches to cumulative risk assessment. The Agency is also
nearing completion of the revision of the Chemical Mixtures Risk
Assessment Guidelines, which present methods for combining risks from
multiple chemicals. In addition, ILSI is independently exploring
appropriate methods and developing a framework for performing a
cumulative risk assessment. ILSI held a workgroup on this subject in
September 1998, and a report is expected in early 1999. The Agency will
continue its ongoing efforts in this area along with examining the ILSI
work and other sources of information in preparation for release of an
Agency draft guidance document by June 1999 with a 60-day comment
period. The guidance will be revised no later than November 1999.
I. Science Policy 9: Selection of Appropriate Toxicity Endpoints for
Risk Assessments of Organophosphates
Most organophosphate (OP) and certain carbamate insecticides exert
their principal toxic effects on insects, mammals, and other animals by
the mechanism of cholinesterase inhibition, which may lead to
neurotoxicity. Measurement of cholinesterase levels in the blood or
nervous system after exposure to OPs has become the most common
endpoint used in risk assessments of this chemical class.
Over the last several years, the Agency has engaged outside
scientists and the regulatory community about how measures of
cholinesterase inhibition should be used in risk assessments. EPA has
also discussed more generally how these data should be viewed along
with other types of data in risk assessments. Two issues focused on
were: (1) The role of blood measures in risk assessment since plasma
and red cell cholinesterases are not part of the nervous system but
they may be an indirect measure of what is occurring in the central and
peripheral nervous systems; and (2) whether plasma cholinesterase
should be treated differently from red blood cell cholinesterase.
In June 1997, OPP made a comprehensive presentation to the SAP on
cholinesterase inhibition. The presentation included a literature
review, a series of case studies, a summary of activities related to
methods of cholinesterase measurement, and a proposed policy to use a
weight-of-evidence approach considering all of the data that might
result in the use of cholinesterase measures in plasma, red blood
cells, or brain for defining critical effects and no-effects levels. In
addition, EPA also asked the SAP about the feasibility of using
measures of peripheral nervous system tissue to replace blood measures,
which largely serve as indirect estimators of cholinesterase inhibition
in the peripheral nervous system in animals. The positions contained in
the paper presented to the SAP, entitled ``Office of Pesticide Programs
Science Policy on the Use of Cholinesterase Inhibition for Risk
Assessments of Organophosphate and Carbamate Pesticides,'' draft April
30, 1997, will be issued for a 60-day comment period in October 1998.
The SAP comments on that document will be provided in the docket with
that Federal Register notice. Revised guidance will be issued no later
than March 1999.
III. How EPA Will Address Comments
A. Comments Already Received
Before and during the TRAC meetings, the Agency received comments
on how to approach and improve its interim policies. Specifically, EPA
received several petitions, including those from the National Food
Processors Association, the Natural Resources Defense Council (NRDC)
and others, a report from the Implementation Working Group (IWG),
letters from the Environmental Working Group, and various
correspondence from Congress and others. These documents will be
considered as the Agency refines its science policies, and will also be
made available through the public docket. Additionally, the U.S. House
Agriculture Committee has held a hearing on FQPA implementation and
there have been legislative or public hearings in California, Idaho,
and
[[Page 58044]]
Michigan as well at which comments were solicited and offered.
B. NRDC Petition
On April 23, 1998, the NRDC and various individuals and other
public interest organizations filed a petition requesting that EPA
issue an interpretive rule/policy statement regarding EPA's
implementation of the FQPA provision concerning the additional 10-fold
factor to protect infants and children. The petition seeks three
specific actions:
1. Issuance of a policy statement/interpretive rule providing that
EPA ``maintain the ten-fold safety factor unless the Administrator has
determined that there are reliable data on [evolving] pre- and post-
natal toxicity and exposure for fetuses, infants, and children.'' The
petition sets forth a minimum set of data that petitioners believe
constitutes ``reliable data'' and requests that the statement/rule
direct EPA to apply the additional 10-fold factor if any of these data
are absent.
2. Convene a ``blue ribbon panel'' to assist EPA ``in determining
when there are `reliable' data for pre- and post-natal toxicity to
fetuses, infants, and children.'' NRDC recommends that this panel be
convened under the auspices of the Children's Health Protection
Advisory Committee.
3. Issuance of a policy statement/interpretive rule providing that,
pending completion of the panel's report, EPA will apply the 10-fold
FQPA factor.
C. Grower Group and Trade Association Petition
On May 26, 1998, EPA received a Petition on Rulemaking Under the
Food Quality Protection Act submitted on behalf of several grower
groups and trade associations. The petition requested EPA to use notice
and comment rulemaking to establish policies and procedures for
implementing FQPA. The petitioners claim that rules are needed to
establish policies and procedures for assessing aggregate exposures,
common mechanism of toxicity, and cumulative effects, and for
determining when the FQPA 10-fold factor may be reduced or removed. The
petitioners state that EPA is using its current science policies as
though they were binding requirements. The petitioners maintain that
neither the advisory panel process nor the notice and comment
rulemaking on individual tolerances appropriately substitute for notice
and comment rulemaking on major procedural or policy issues.
D. IWG Report
The IWG, a coalition of farm, food, manufacturing, and pest
management organizations, issued a ``road map'' report on June 18,
1998, which ``presents the IWG's views on how EPA can ensure a more
balanced and workable implementation of FQPA.'' The sections of the
report include the IWG's general recommendations, their interpretation
of Congress's intent, EPA actions to date, ``an approach to aggregate
risk assessment and the assessment of cumulative effects of chemicals
with a common mechanism of toxicity,'' other recommendations, and issue
papers.
IV. EPA's Interim Approach While Assessing the Nine Science
Policies
A. Interim Approach
While refining its approach to the nine issues, EPA will use the
policies described in its interim science policy documents when making
decisions on actions such as establishing tolerances for registrations
under section 3 of FIFRA, emergency exemptions under section 18 of
FIFRA, and tolerance reassessments.
B. EPA's Approach to Notice and Comment
The Agency intends to refine each of the nine science policy issues
by seeking public input through the notice and comment process
explained in this notice. In announcing the availability of the nine
science policy documents for comment, the Agency will:
1. Identify any significant comments EPA has already received on
the various policy documents.
2. Where appropriate, ask specific questions based on pivotal
issues in those comments.
3. Provide a comment period through the Federal Register notice on
each science policy issue, as described in this notice, after which the
Agency will respond to significant comments received in response to the
Agency's notices, and revise each policy as appropriate.
C. Documents Available in the Docket
The following documents prepared for the TRAC are available in the
docket: A table entitled ``Framework for Refining FQPA Science Policy''
and a timeline entitled ``Schedule for Release of Guidance on Science
Policy Issues.'' In addition, a compendium of the Agency's current
operating guidelines is available in the docket; however, comment is
not being requested at this time on these documents since they are
being revised. Opportunity for comment will be offered as noted earlier
in this notice.
V. Policies Not Rules
The numerous science policy documents discussed in this notice are
intended to provide guidance to EPA personnel and decision-makers, and
to the public. As guidance documents and not rules, these policies are
not binding on either EPA or any outside parties. Although these
guidance documents provide a starting point for EPA risk assessments,
EPA will depart from these policies where the facts or circumstances
warrant. In such cases, EPA will explain why a different course was
taken. Similarly, outside parties remain free to assert that a given
policy is not appropriate for a specific pesticide or that the
circumstances surrounding a specific risk assessment demonstrate that a
given policy should be abandoned.
Throughout this notice, EPA has stated that it will make available
revised guidances after consideration of public comment. Public comment
is not being solicited for the purpose of converting these policy
documents into binding rules. EPA will not be codifying these policies
in the Code of Federal Regulations. EPA is soliciting public comment so
that it can make fully informed decisions regarding the content of
these guidances.
The ``revised'' guidances will not be unalterable documents. Once a
``revised'' guidance document is issued, EPA will continue to treat it
as guidance, not a rule. Accordingly, on a case-by-case basis EPA will
decide whether it is appropriate to depart from the guidance or to
modify the overall approach in the guidance. In the course of
commenting on the individual guidance documents, EPA would welcome
comments that specifically address how the guidance documents can be
structured so that they provide meaningful guidance without imposing
binding requirements.
VI. Closing
This is EPA's approach to providing for notice and comment
regarding the nine science policy issues discussed above and on the
timing of the process set out in the framework. Under this approach,
for each science policy issue described above, a document which
describes the Agency's approach for each issue will be published
separately, as available, for public comment through the Federal
Register.
[[Page 58045]]
VII. Public Record and Electronic Submissions
The official record for this action, as well as the public version,
has been established for this action under docket control number ``OPP-
00557'' (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 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-00557.'' Electronic comments on this
action may be filed online at many Federal Depository Libraries.
List of Subjects
Environmental protection, FQPA, Pesticides.
Dated: October 23, 1998.
Lynn R. Goldman,
Assistant Administrator for Prevention, Pesticides and Toxic
Substances.
[FR Doc. 98-29013 Filed 10-28-98; 8:45 am]
BILLING CODE 6560-50-F
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