United States       Prevention, Pesticides     EPA712-C-96-275
          Environmental Protection    and Toxic Substances     February 1996
          Agency         (7101)
&EPA    Biochemicals Test
          OPPTS 880.1400
          Discussion of Formation
          of Impurities

     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.).

     Final  Guideline Release: This guideline  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   and   ftp:
fedbbs.access.gpo.gov    (IP,    internet:     http://
fedbbs.access.gpo.gov, or call 202-512-0132 for disks  or paper copies.
This guideline is also available electronically in ASCII and PDF (portable
document format) from the EPA Public Access Gopher  (gopher.epa.gov)
under the heading "Environmental Test  Methods and Guidelines."

OPPTS 880.1400   Discussion of formation of impurities.
     (a) Scopeó(1) Applicability. This guideline is intended to meet test-
ing requirements of the  Federal Insecticide, Fungicide,  and Rodenticide
Act (FIFRA) (7 U.S.C. 136, et seq.}.

     (2) Background. The source material used in developing this har-
monized OPPTS test guideline is OPP guideline 151-12.

     (b) Unintentional ingredients. As required by 40  CFR 158.167,  a
registration application shall include a discussion concerning potential for-
mation and presence of unintentional ingredients in the product in quan-
tities which may produce adverse human or environmental effects.

     (1) As described under OPPTS 830.1670, such unintentional ingredi-
ents may be introduced during the following manufacturing process:

     (i) With the starting  material, process solvents, equipment, packaging,
and other sources.

     (ii) From side reactions in the manufacturing process.

     (iii) From interactions between ingredients.

     (iv) From the  degradation of ingredients.

     (2) The applicant should base his  discussion on established chemical

     (3) For biochemicals, the  unintentional ingredients can include but
are not  limited to  extraneous host residues and residues of contaminants
that remain following the extraction or purification process.