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Pesticide Science Policies: Water Treatment Effects on Pesticide Removal and Transformation; Notice of Availability

Note: EPA no longer updates this information, but it may be useful as a reference or resource.


 [Federal Register: November 21, 2001 (Volume 66, Number 225)]
[Notices]
[Page 58485-58489]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21no01-87]

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ENVIRONMENTAL PROTECTION AGENCY

[OPP-00731; FRL-6792-9]

 
Pesticide Science Policies: Water Treatment Effects on Pesticide 
Removal and Transformation; Notice of Availability

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: To assure that EPA's policies related to implementing the Food 
Quality Protection Act of 1996 (FQPA) are transparent and open to 
public participation, EPA is soliciting comments on the pesticide draft 
science policy document entitled ``The Incorporation of Water Treatment

[[Page 58486]]

Effects on Pesticide Removal and Transformations in FQPA Drinking Water 
Assessments.'' This notice is one in a series concerning science policy 
documents related to the implementation of the Federal Food, Drug, and 
Cosmetic Act (FFDCA), as amended by FQPA.

DATES: Comments for the draft science policy document, identified by 
docket control number OPP-00731, must be received on or before January 
22, 2002.

ADDRESSES: Comments may be submitted by mail, electronically, or in 
person. Please follow the detailed instructions for each method as 
provided in Unit I. of the SUPPLEMENTARY INFORMATION. To ensure proper 
receipt by EPA, it is imperative that you identify docket control 
number OPP-00731 in the subject line on the first page of your 
response.

FOR FURTHER INFORMATION CONTACT: James Hetrick, Office of Prevention, 
Pesticides and Toxic Substances (7505C), Environmental Protection 
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460; telephone 
number: (703) 305-5237; fax number: (703) 305-6309; e-mail address: 
hetrick.james@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you manufacture 
or formulate pesticides. Potentially affected categories and entities 
may include, but are not limited to:

------------------------------------------------------------------------
                                                          Examples of
           Categories                 NAICS codes         potentially
                                                       affected entities
------------------------------------------------------------------------
Pesticide producers               32532               Pesticide
                                                       manufacturers
                                                      Pesticide
                                                       formulators
------------------------------------------------------------------------

    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed could also be affected. The 
North American Industrial Classification System (NAICS) codes have been 
provided to assist you and others in determining whether or not this 
action might apply to certain entities. If you have any questions 
regarding the applicability of this action to a particular entity, 
consult the person listed under FOR FURTHER INFORMATION CONTACT.

B. How Can I Get Additional Information, Including Copies of this 
Document or Other Related Documents?

    1. Electronically. You may obtain electronic copies of this 
document, the draft science policy document, and certain other related 
documents that might be available from the Office of Pesticide 
Programs' Home Page at http://www.epa.gov/pesticides/. On the Office of 
Pesticide Programs' Home Page select ``FQPA'' and then look up the 
entry for this document under ``Science Policies.'' You can also go 
directly to the listings at the EPA Home Page at http://www.epa.gov/. 
On the Home Page select ``Laws and Regulations,'' ``Regulations and 
Proposed Rules,'' and then look up the entry for this document under 
``Federal Register--Environmental Documents.'' You can go directly to 
the Federal Register listings http://www.epa.gov/fedrgstr/.
    2. Fax-on-demand. You may request a faxed copy of the draft science 
policy document, as well as supporting information, by using a faxphone 
to call (202) 401-0527. Select item 6088 for the document entitled 
``The Incorporation of Water Treatment Effects on Pesticide Removal and 
Transformations in FQPA Drinking Water Assessments.'' You may also 
follow the automated menu.
    3. In person. The Agency has established an official record for 
this action under docket control number OPP-00731. In addition, the 
documents referenced in the framework notice, which published in the 
Federal Register of October 29, 1998 (63 FR 58038) (FRL-6041-5), under 
docket control number OPP-00557, are considered as part of the official 
record for this action under docket control number OPP-00731 even 
though not placed in the official record. The official record consists 
of the documents specifically referenced in this action, and other 
information related to this action, including any information claimed 
as Confidential Business Information (CBI). This official record 
includes the documents that are physically located in the docket, as 
well as the documents that are referenced in those documents. The 
public version of the official record does not include any information 
claimed as CBI. The public version of the official record, which 
includes printed, paper versions of any electronic comments submitted 
during an applicable comment period is available for inspection in the 
Public Information and Records Integrity Branch (PIRIB), Rm. 119, 
Crystal Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA, from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.

C. How and to Whom Do I Submit Comments?

    You may submit comments through the mail, in person, or 
electronically. To ensure proper receipt by EPA, it is imperative that 
you identify docket control number OPP-00731 in the subject line on the 
first page of your response.
    1. By mail. Submit your comments to: Public Information and Records 
Integrity Branch (PIRIB), Information Resources and Services Division 
(7502C), Office of Pesticide Programs (OPP), Environmental Protection 
Agency, 1200 Pennsylvania, Ave., NW., Washington, DC 20460.
    2. In person or by courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Information Resources 
and Services Division (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, Rm. 119, Crystal Mall #2, 1921 
Jefferson Davis Hwy., Arlington, VA. The PIRIB is open from 8 a.m. to 4 
p.m., Monday through Friday, excluding legal holidays. The PIRIB 
telephone number is (703) 305-5805.
    3. Electronically. You may submit your comments electronically by 
e-mail to: opp-docket@epa.gov, or you can submit a computer disk as 
described above. Do not submit any information electronically that you 
consider to be CBI. Avoid the use of special characters and any form of 
encryption. Electronic submissions will be accepted in WordPerfect 6.1/
8.0 or ASCII file format. All comments in electronic form must be 
identified by docket control number OPP-00731. Electronic comments may 
also be filed online at many Federal Depository Libraries.

D. How Should I Handle CBI That I Want to Submit to the Agency?

    Do not submit any information electronically that you consider to 
be CBI. You may claim information that you submit to EPA in response to 
this document as CBI 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. In addition to one complete 
version of the comment that includes any information claimed as CBI, a 
copy of the comment that does not contain the information claimed as 
CBI must be submitted for inclusion in the public version of the 
official record. Information not marked confidential will be included 
in the public version

[[Page 58487]]

of the official record without prior notice. If you have any questions 
about CBI or the procedures for claiming CBI, please consult the person 
listed under FOR FURTHER INFORMATION CONTACT.

E. What Should I Consider As I Prepare My Comments for EPA?

    EPA invites you to provide your views on the various draft science 
policy documents, new approaches we have not considered, the potential 
impacts of the various options (including possible unintended 
consequences), and any data or information that you would like the 
Agency to consider. You may find the following suggestions helpful for 
preparing your comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide solid technical information and/or data to support your 
views.
    4. If you estimate potential burden or costs, explain how you 
arrived at the estimate.
    5. Indicate what you support, as well as what you disagree with.
    6. Provide specific examples to illustrate your concerns.
    7. Make sure to submit your comments by the deadline in this 
notice.
    8. At the beginning of your comments (e.g., as part of the 
``Subject'' heading), be sure to properly identify the document you are 
commenting on. To ensure proper receipt by EPA, it is imperative that 
you identify docket control number OPP-00731 in the subject line on the 
first page of your response. You may also provide the name, date, and 
Federal Register citation.

II. Background Information

    On August 3, 1996, FQPA was signed into law. The FQPA significantly 
amended the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 
and the 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 and strengthened health protections for infants and 
children from pesticide risks.
    Thereafter, the Agency established the Food Safety Advisory 
Committee (FSAC) as a subcommittee of the National Advisory Council for 
Environmental Policy and Technology (NACEPT) to assist in soliciting 
input from stakeholders and to provide input to EPA on the broad policy 
choices facing the Agency and on strategic direction for the Office of 
Pesticide Programs (OPP). The Agency has used the interim approaches 
developed through discussions with FSAC to make regulatory decisions 
that meet the new FFDCA standard, but that could be revisited if 
additional information became available or as the science evolved. In 
addition, the Agency seeks independent review and public participation, 
generally through presentation of the science policy issues to the 
FIFRA science advisory panel (SAP) a group of independent, outside 
experts who provide peer review and scientific advice to OPP.
    During 1998 and 1999, EPA and the United States Department of 
Agriculture (USDA) established a second subcommittee of NACEPT, the 
Tolerance Reassessment Advisory Committee (TRAC) to address FFDCA 
issues and implementation. TRAC comprised more than 50 representatives 
of affected user, producer, consumer, public health, environmental, 
states, and other interested groups. The TRAC met from May 27, 1998, 
through April 29, 1999.
    In order to continue the constructive discussions about FFDCA, EPA 
and USDA have established, under the auspices of NACEPT, the Committee 
to Advise on Reassessment and Transition (CARAT). The CARAT provides a 
forum for a broad spectrum of stakeholders to consult with and advise 
the Agency and the Secretary of Agriculture on pest and pesticide 
management transition issues related to the tolerance reassessment 
process. The CARAT is intended to further the valuable work initiated 
by the FSAC and TRAC toward the use of sound science and greater 
transparency in regulatory decision making, increased stakeholder 
participation, and reasonable transition strategies that reduce risks 
without jeopardizing American agriculture and farm communities.
    As a result of the 1998 and 1999 TRAC process, EPA decided that the 
implementation process and related policies would benefit from 
providing notice and comment on major science policy issues. The TRAC 
identified nine science policy areas it believed were key to 
implementation of tolerance reassessment. EPA agreed to provide one or 
more documents for comment on each of the nine issues by announcing 
their availability in the Federal Register. In a notice published in 
the Federal Register of October 29, 1998 (63 FR 58038), EPA described 
its intended approach. Since then, EPA has been issuing a series of 
draft documents concerning the nine science policy issues. This notice 
announces the availability of the draft science policy document 
concerning drinking water treatment.

III. Summary of ``The Incorporation of Water Treatment Effects on 
Pesticide Removal and Transformations in Food Quality Protection 
Act Drinking Water Assessments''

    The FQPA of 1996 requires that all tolerances for pesticide 
chemical residues in or on food consider anticipated dietary exposure 
and all other exposures for which there is reliable information. 
Drinking water is considered a potential pathway of dietary exposure to 
pesticides. Because drinking water for a large percentage of the 
population is derived from public water systems which normally treat 
raw water prior to consumption, the impact of water treatment on 
pesticide removal and transformation needs to be considered in drinking 
water exposure for risk assessments completed under FQPA. Treated 
drinking water for the purpose of FQPA exposure assessment will be 
defined as ambient ground or surface water which is either chemically 
or physically altered using technology prior to human consumption. 
Therefore, the objectives of this science policy paper are to:
    1. Present a preliminary literature review on the impact of 
different treatment processes on pesticide removal and transformation 
in treated drinking water derived from ground and surface water 
sources.
    2. Describe how OPP will consider the impacts of drinking water 
treatment in drinking water exposure assessments under FQPA.

IV. Literature Review

    A wide variety of factors must be taken into account to assess the 
impact of drinking water treatment on the levels of different 
pesticides in drinking water. It is important to note that a sizeable 
proportion of the nation, approximately 23 million people, obtain their 
drinking water from private wells and other sources that undergo no 
treatment. For those drinking water sources that are treated, available 
survey information establishes that there are many distinct types of 
water treatment processes (and many more combinations of processes) in 
use throughout the United States. Nearly all public water supply 
systems use some form of disinfection, and a series of conventional 
treatment processes (coagulation-flocculation, sedimentation, and 
filtration). The processes that appear to have the most impact on 
pesticide removal granular

[[Page 58488]]

activated carbon (GAC) and powdered activated carbon (PAC) - are 
commonly found or used in larger water supply systems but, because of 
high costs, are rarely used by the smallest systems. Other methods, 
such as ``softening,'' reverse osmosis, and air stripping are also less 
frequently used to remediate water quality concerns. In sum, there is 
enormous spatial and temporal variability in the types of treatment 
applied to drinking water.
    EPA's preliminary review of the literature indicates that 
conventional treatment (such as coagulation/flocculation, 
sedimentation, and filtration) has little or no effect on the removal 
of mobile (hydrophilic or lipophobic) pesticides. Disinfection and 
softening can facilitate alteration in the chemical structure of the 
pesticide, or transformation. The type of disinfectant used and the 
length of contact time between the water and disinfectant are factors 
which affect the impact on pesticide transformation. There is little 
information on the chemical identity of transformation products formed 
as the result of disinfection. However, disinfection can produce toxic 
by-products of some pesticides (e.g., oxons from organophospates). The 
impact of softening on pesticide transformation is dependent on the 
potential for alkaline-catalyzed hydrolysis of the pesticide.
    The FIFRA SAP evaluated the literature review and concurred with 
the conclusions (www.epa.gov/pesticides/scipoly/sap/2000/
index.htm#september). The SAP stated that immobile (hydrophobic/
lipophilic) pesticides may be removed by conventional water treatment 
processes.

V. Proposed Policy

    OPP is announcing and seeking public comment on a policy to provide 
a systematic approach for considering drinking water treatment effects 
on pesticide removal and transformation in FQPA risk assessments. 
Because most surface source drinking water receives some form of water 
treatment prior to human consumption, the proposed treatment policy is 
generally applicable to surface source drinking water. A similar 
assumption cannot be made for drinking water systems using ground water 
because of the importance of private wells in rural areas. Private 
wells are not generally linked to water treatment systems prior to 
human consumption. This policy is based on scientific conclusions 
reached as a result of OPP's literature review and on our assessment of 
the availability of information for specific pesticides on water 
treatment effects:
     The Environmental Fate and Effects Division (EFED) will 
provide available information on the potential and measured effects 
from drinking water treatment (e.g., flocculation, coagulation, 
sedimentation, filtration, chlorination, softening, and GAC/PAC 
treatment) to the HED Metabolism Assessment Review Committee (MARC). 
The MARC will evaluate this information and determine which, if any, 
transformation and degradation products might be of toxicological 
concern. This information will also be considered in FQPA Safety Factor 
decisions.
     OPP will not generally conclude that treatment mitigates 
exposure for a specific pesticide without supporting evidence. 
Therefore, if sufficient pesticide-specific information is not 
available on effects of water treatment processes, or if sufficient 
information is not available on the extent to which specific processes 
are employed within the pesticide use area, FQPA drinking water 
assessments will be conducted using pesticide concentrations in raw or 
ambient waters to represent pesticide concentrations in finished 
drinking water. This policy is based on the fact that conventional 
water treatment processes (coagulation/flocculation, sedimentation, and 
filtration) are not expected to remove mobile pesticides during 
treatment.
     If sufficient pesticide-specific information is available 
on effects of a water treatment processes, as well as information on 
the extent to which such processes are employed within the pesticide 
use area, EFED will attempt to describe quantitatively the potential 
effects of drinking water treatment for that pesticide in the drinking 
water assessment. This description will include effects of degradation 
and formation of transformation products.
     Monitoring data on finished drinking water may also 
represent in aggregate the effects of treatment in the study area. 
However, because of the inherent variability associated with water 
treatment processes, with source water quality, and the limited 
availability of monitoring data on pesticides in finished drinking 
water, extrapolating such results to areas outside of the area 
monitored must be considered on a case-by-case basis. It is anticipated 
that quantitation of drinking water treatment effects will be limited 
to pesticides with extensive monitoring data on finished water (e.g., 
atrazine) or pesticides with monitoring data on finished water from 
focused or limited use areas (e.g., molinate). Extrapolating treatment 
effects across compounds with similar structures will be considered on 
a case-by-case basis.

VI. Questions for Public Comment

    1. Do the scientific data demonstrate clear quantitative 
relationships exist between the physical/chemical properties of 
particular pesticide classes and the impacts of specific water 
treatment processes?
    2. Based on its technical review of the literature on the impacts 
of different treatment processes on levels of pesticide residues in 
drinking water, OPP is leaning toward an interim approach which 
assumes, in the absence of representative pesticide-specific water 
plant monitoring data, that residues in finished drinking water will be 
the same as levels in such water prior to treatment. Given the 
objective of accurately estimating pesticide concentrations in drinking 
water, do the scientific data support this approach? How would an 
approach be developed based on the state of knowledge about the impact 
of treatment on pesticides? Under what circumstances can OPP use data 
on the impacts of a specific treatment process on several pesticides in 
a chemical class to support a general conclusion about all pesticide in 
that class?
    3. During disinfection with chlorine, pesticides such as 
organophosphates can be oxidized to form toxic degradation products. 
What other classes of pesticides may be transformed by drinking water 
treatment processes to form toxic byproducts? What issues related to 
pesticide transformation should OPP be aware of?
    4. Laboratory jar tests are often employed to determine if a 
regulated contaminant, including some pesticides, in raw water can be 
removed by a given treatment process. What are the advantages and 
disadvantages of using results of jar tests as the basis of evaluating 
whether the pesticide will be eventually removed in the actual water 
treatment plant? How might these results be used to adjust raw water 
concentrations for use in human health risk assessment? What are the 
advantages and disadvantages of using other types of data, e.g., paired 
samples from field monitoring, or pilot plant data.
    5. Studies cited in the literature review indicate that many 
factors, such as raw water composition, water treatment method, and 
treatment plant conditions, may affect the removal of pesticides. What 
issues should OPP be considering in determining the potential impact of 
these factors on the percent removal and transformation of

[[Page 58489]]

pesticides by different water treatment plants?
    6. What additional water treatment data from other studies, which 
either support or are inconsistent or contradict the data presented in 
the preliminary literature review, should OPP consider? Please submit 
any data that would provide information on the impacts of water 
treatment on additional pesticides or classes of pesticides.
    7. For example, some pesticides, including carbamates and 
organophosphates, with hydrolysis half-lives of less than 1 day in 
alkaline (pH 9) water are observed to be ``removed'' during lime-soda 
softening (pH 10~11) by alkaline hydrolysis. Can this observation be 
generalized in predicting whether a pesticide with alkaline abiotic 
hydrolysis half-life of less than 1 day will be ``removed'' through 
water treatment?
    8. The effects of water treatment on pesticide residues in drinking 
water can be assessed by regression modeling of important parameters 
with removal efficiency, experimental or laboratory studies, and actual 
field monitoring. What other approaches or methods can be used to 
assess water treatment effects? What are the pros and cons of these 
methods?
    9. What types of data are needed regarding the extent and manner of 
use of a particular drinking water treatment process in order to use 
the data on the impact of such method on pesticide concentrations in 
finished drinking water in a deterministic or probabilistic exposure 
assessment?

VII. Policies Not Rules

    The draft science policy document discussed in this notice is 
intended to provide guidance to EPA personnel and decisionmakers, and 
to the public. As a guidance document and not a rule, the policy in 
this guidance is not binding on either EPA or any outside parties. 
Although this guidance provides a starting point for EPA risk 
assessments, EPA will depart from its policy 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 policy is not appropriate for a specific pesticide or that the 
circumstances surrounding a specific risk assessment demonstrate that a 
policy should be abandoned.
    EPA has stated in this notice that it will make available revised 
guidance after consideration of public comment. Public comment is not 
being solicited for the purpose of converting any policy document into 
a binding rule. EPA will not be codifying this policy in the Code of 
Federal Regulations. EPA is soliciting public comment so that it can 
make fully informed decisions regarding the content of each guidance 
document.
    The ``revised'' guidance will not be unalterable. 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 inviting 
comment on each guidance document, EPA would welcome comments that 
specifically address how a guidance document can be structured so that 
it provides meaningful guidance without imposing binding requirements.

List of Subjects

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Pesticides and pests.

    Dated: November 8, 2001.
Stephen Johnson,
Assistant Administrator for Prevention, Pesticides and Toxic 
Substances.
[FR Doc. 01-28973 Filed 11-20-01; 8:45 am]
BILLING CODE 6560-50-S 

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