UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

                     WASHINGTON, D.C. Z0460
                                                        OFFICE Of
                                                PESTICIDES AND TOXIC SUBSTANCES
MEMORANDUM.

TO:      Edwin L. Johnson,  Director
         Office of Pesticide  Programs  (TS-766C
SUBJECT : .RetuOT^ofeWaledv^to^eg^ts^             —
         ACTION MEMORANDUM

     On June 30,  1983,  I  approved  a registration standard
and a guidance package  for  naled.   For the following reasons
I recommend that  you return naled  to the  normal registration
process .

     In 1978 naled was  referred  to OPP for RPAR review en
the basis of suspected  mutagenic,  fetctoxic and reproductive
effects-.  Naled is also a metabolite of dichlorvos (DDVP),
which had also been referred  for RPAR review based on
potential oncogenic, mutagenic,  reproductive,  fetotoxic and
neuroccxic effects.

     On September 30, 1982,  the  pre-RPAR  review for DDVP was
completed and a decision  document  was published.   The docu-
ment concluded' that the existing evidence was  inadequate to
initiate an RPAR  for DDVP.   Specifically,  no definitive
evidence of teratogenicity ,  fetotoxicity  or neurotoxicity
was found.  With  regard to  possible  carcinogenicity and
mutagenicity , it  was concluded that  additional  data were
needed to resolve those issues.  A Section 3(c)(2)(B)  letter
was sent to registrants to  require certain mutagenic tests
for DDVP on March 23, 1983.   A bioassay being conducted by
the National Cancer Institute will be reviewed  upon its
completion to resolve the carcinogenicity issue.   According-
ly, .at. present there is no  basis for initiating  an RPAR on
nale'd as a possible metabolite of  DDV? .

-------
     For naied itself,  the data  base  is  incomplete  for
determining whether to  begin  an  RPAR  review.   On  April  3,
1981, a data- call in  letter was  issued  to  registrants
requiring a chronic feeding study,  an oncogenic study
in two species, a teratology  study  in one  species and
a reproduction study  in one species.  On April 8, 1982
the Chevron Chemical  Company  committed  to  performing these
studies.  These are due in April, 1985.  In addition, the
registration standard requires certain mutagenicity studies
All these data will be  reviewed  to  determine whether a
basis exists for conducting an RPAR.

     In summary,  no valid evidence  exists  which would
justify beginning an  RPAR and the necessary data  gaps on
naled are now being filled.   I therefore recommend that you
remove naled from the RPAR referral list and return it  to
the normal registration process.
Approve:

Disapprove:	

Dace:     //
                            Dougias ID. Campt, Director
                            Registration Division (TS-767C)

-------