United States       Prevention, Pesticides     EPA712-C-95-010
          Environmental Protection    and Toxic Substances     August 1995
          Agency        (7101)
&EPA    Product Properties
          Test Guidelines
          OPPTS 830.1670
          Discussion of Formation
          of Impurities
                'Public Draft"

     This guideline is one of a series of test guidelines that have been
developed by the Office of Prevention, Pesticides and Toxic Substances,
United States Environmental Protection Agency for use in the testing of
pesticides and toxic substances, and the development of test data that must
be submitted to the Agency for review under Federal regulations.

     The Office of Prevention,  Pesticides and Toxic Substances (OPPTS)
has  developed this guideline through a  process of  harmonization that
blended the testing  guidance and requirements that existed in the  Office
of Pollution Prevention and Toxics  (OPPT) and appeared in Title 40,
Chapter I,  Subchapter R of the Code of Federal Regulations  (CFR), the
Office of Pesticide Programs (OPP) which appeared in publications of the
National Technical  Information Service (NTIS) and the guidelines pub-
lished by the Organization for Economic Cooperation and Development

     The purpose of harmonizing these guidelines into a single  set of
OPPTS  guidelines is to minimize variations among the testing procedures
that must be performed to meet the data requirements of the U. S. Environ-
mental Protection Agency under the Toxic  Substances Control Act (15
U.S.C. 2601) and the Federal Insecticide,  Fungicide and Rodenticide Act
(7U.S.C. I36,etseq.).

     Public Draft Access Information: This draft guideline is part of a
series of related harmonized guidelines that  need to  be considered as a
unit. For copies: These guidelines are available electronically from the
EPA Public Access Gopher (gopher.epa.gov) under the heading "Environ-
mental Test Methods and Guidelines" or in paper by  contacting the OPP
Public    Docket    at    (703)    305-5805    or    by    e-mail:

     To Submit Comments: Interested persons are invited to submit com-
ments. By mail: Public Docket and Freedom of Information Section,  Office
of Pesticide Programs, Field Operations Division (7506C), Environmental
Protection Agency,  401  M  St.  SW.,  Washington, DC 20460. In person:
bring to: Rm. 1132, Crystal Mall #2, 1921 Jefferson Davis Highway, Ar-
lington, VA. Comments may also be submitted  electronically by sending
electronic mail (e-mail) to: guidelines@epamail.epa.gov.

     Final  Guideline Release:  This document is available from the U.S.
Government Printing Office, Washington, DC 20402 on The Federal Bul-
letin Board. By modem dial 202-512-1387, telnet:  federal.bbs.gpo.gov
3001, or call 202-512-1530 for disks or  paper  copies.  This guideline is
available in ASCII and PDF (portable document format).

OPPTS 830.1670  Discussion of formation of impurities.
     (a) Scope—(1) Applicability. This guideline is intended to meet test-
ing  requirements  of  both  the Federal   Insecticide,  Fungicide,  and
Rodenticide Act (FIFRA) (7 U.S.C. 136, et seq.} and the Toxic Substances
Control Act (TSCA) (15 U.S.C. 2601).

     (2) Background.  The source material  used in developing this har-
monized OPPTS test guideline is 40 CFR 158.167.

     (b) Information required.  The applicant must provide a discussion
of the  impurities that may be present in the product,  and why they may
be present. The discussion should be based on established chemical theory
and  on what the  applicant knows about the starting materials, technical
grade of active ingredient, inert ingredients, and production or formulation
process. If the applicant has reasons to believe that an impurity that EPA
would  consider toxicologically significant may be  present, the discussion
must include  an expanded discussion of the possible formation of the im-
purity and the amounts at which  it might be present. The impurities which
must be discussed are the following, as applicable:

     (c) Technical grade active ingredients and products produced by
an integrated system.  (1) Each impurity associated with the active ingre-
dient which was found to be present in any analysis of the product con-
ducted by or for the applicant.

     (2) Each other impurity which  the applicant  has reason to  believe
may be present in his product at any time before use at a  level  «0.1
percent (1,000 ppm) by weight of the technical grade of the active ingredi-
ent, based on what he knows about the following:

     (i) The composition (or composition range)  of each starting  material
used to produce his product.

     (ii) The impurities which he knows are present (or believes are likely
to be present) in the starting  materials, and the known or presumed level
(or range of levels) of these impurities.

     (iii) The intended reactions  and  side  reactions which may occur in
the production of the product, and the relative amounts of byproduct impu-
rities produced by such reactions.

     (iv) The possible  degradation of the ingredients in the product after
its production but prior to its use.

     (v) Post-production reactions between the ingredients in the  product.

     (vi) The  possible migration of components of packaging materials into
the pesticide.

     (vii) The possible carryover of contaminants from use of production
equipment previously used to produce other products or substances.

     (viii) The process control, purification and quality control measures
used to produce the product.

     (d) Products not produced by an integrated system. Each impurity
associated with the  active ingredient which the applicant has  reason to
believe  may be  present  in the product at any time before  use at a
level « 0.1 percent (1,000 ppm) by weight of the product based on what
he knows about the following:

     (1) The possible  carryover  of impurities  present in  any registered
product which serves as the source of any of the product's active ingredi-
ents. The  identity and level of impurities in the registered source need
not be discussed or quantified unless known to the formulator.

     (2) The possible carryover of impurities present in the inert ingredi-
ents in the product.

     (3) Possible reactions occurring during the  formulation of the product
between any of its active ingredients, between the active ingredients and
inert ingredients,  or between  the  active ingredient  and the production

     (4) Post-production reactions  between any of the product's  active in-
gredients and any other component of the product or its packaging.

     (5) Possible migration of packaging materials into the product.

     (6) Possible contaminants  resulting  from earlier use of equipment to
produce other products.

     (e) Expanded discussion. On a case-by-case basis, the Agency may
require an expanded discussion of information on impurities:

     (1) From other possible chemical reactions.

     (2) Involving other ingredients.

     (3) At additional points in the production or formulation process.