United Stnn
             Environmental Protection
             Aqcncy
Off to of
Pastickfes md Tonic Subfancn
WuhinjtonOC 20460
January   1982
3EPA
              Oxyfiuorfen (Goal 2E
             Position  Document No.  4

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          CHOFIECRFEN
       POSITICN DOCUMENT

 Office of Pesticide Programs
Environmental Protection Agency

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                          - flCKNDWLEDGEMEMTS -

EPA OXYFLUORFEN TEAM

    Frank Beck, Agronomist, BFSD
    Jolene Chinchilli, Project Manager, SPRD
    Katharine Devine, Econonist, BFSD
    William Dykstra, Biochemist, HED
    Linda Garczynski, Writer/Editor, SPRD
    Timothy Gardner, Section Head, SPRD
    Homer Hall, Branch Chief, SPRD
    Robert Hitch, Fish and Wildlife Biologist, HED
    Cara Jablon, Attorney, OGC
    Van Kozak, Chemist, HED
    Irving Mauer, Geneticist, HED
    Tom Miller, Project Manager, SPRD
    Richard Mountfort, Product Manager, RD
    R.B. Perfetti, Chemist, HED
    Richard Petrie, Agronomist, BFSD
    Emil Regelman, Environmental Chemist, HED
    Joseph Reinert, Chemist, HED
    Amy Rispin, Environmental Chemist, HED
    Dudley E. Thompson, Attorney Advisor, SPRD

OTHER AQCNOWLEDGEMENTS

    Vickie Vaughn-Dellarco, REAG
    Bernard HaJberman, GAG
    Robert McGaughy, CAG

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                                   Oxyfluorfen
                                      PD 4
                                Table of Contents
                                                                        Page
I.  Introduction	  1
    A. Sunmary of Position Document 1/2/3	  1
       1. Risk	  2
       2. Benefits	  2
       3. Risk/Benefit Analysis and Regulatory Options	  2
       4. Proposed Regulatory Decision	  4
    B. Request for Garments	  7
II. Revisions and Amendments  to PD 1/2/3 - Exposure and Risk	  8
III. Analysis of Garments	 12
    A. Comments Relating  to Risk	 12
    B. Garments Relating to Benefits	 13
    C. Garments Relating  to Regulatory Options - Respirator
       Requirement for Mixer/Loader/Applicators	 13
Appendix A - Revised Exposure and  Risk Tables from the Oxyfluorfen
             Position Document 1/2/3
Appendix B - Comments from Scientific Advisory Panel and USDA

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                                List of Tables

                                                                        Page
1. Carcinogenic Risk to Agricultural Workers and  to  the  General
   Population Associated with the Use of PCE-Contaminated
   Qxyfluorfen	   3

2. Adjusted Lifetime Average Daily Worker Exposure to PCE  from
   Uses of Qxyfluorfen	   9

3. Adjusted Maximum Dietary Exposure to PCE from  Uses of
   Qxyfluorfen	  10

4. Carcinogenic Risk to Agricultural Workers and  the General Public
   Associated with the Uses of PCE-Contaminated Qxyfluorfen	  11

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                  Executive Summary


Oxyfluorfen  (Goal 2E) was referred for Rebuttable  Presumption
Against Registration  (RPAR) review in January,  1980,  because
pesticide products containing oxyfluorfen were  shown  to  be
contaminated with perchloroethylene  (PCE), a demonstrated
liver carcinogen in B6C3F1 mice.  The review was initiated
because of the potential for human risk via dietary and
applicator exposure.

Goal 2E is the only registered product containing  oxyfluorfen.
It is registered as a herbicide for  both pre-emergence and
post emergence control of certain weed species  on  conifer
seedbeds and transplants, bearing and nonbearing tree fruits
and nuts, soybeans and field corn (USDA Witchweed  Eradication
Program).  The sole producer and registrant is  the Rohm  and
Haas Company of Philadelphia, Pennsylvania.

In March 1981, the Agency issued a position document
integrating  the presumption against  registration and  the
risk/benefit analysis (position document 1/2/3).   In  this
document, the Agency proposed to limit the level of the  PCE
contaminant  to 200 ppm or less.  This reflected the level
the registrant had stated was both economically and technically
feasible.  Risks estimated by the Agency at the 200 ppm
level for the PCE contaminant were not large and were considered
to be outweighed by the benefits of  the use of oxyfluorfen.

The risk estimate for applicators was based on  a very
conservative model of inhalational exposure rather than
actual field measurements.  Because  of the risk estimates
associated with this model, the Agency proposed to require,
within six months of the final decision, the use of respirators
by mixer/loader/ applicators for currently registered and
proposed uses to reduce inhalational exposure, unless the
registrant submitted actual monitoring data showing levels
of inhalational exposure significantly lower than  those
estimated.

The Agency recommended in the PD 1/2/3 the continuation  of
registration for use on conifers and nonbearing tree  fruits
and nuts, since the relatively small risks to applicators
for these uses were determined to be exceeded by the  benefits.

The pending registration actions for Goal at the initiation
of the RPAR review were for soybeans, field corn and  bearing
tree fruits/nuts.  The recommended decision in  the PD 1/2/3
was to approve these proposed registrations on  condition
that the registrant provide necessary data required to
support full registration.  These conditional registrations
were subsequently approved.

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During this review, the Agency also determined that for uses
of Goal, data are currently inadequate to properly assess
certain possible adverse effects of oxyfluorfen itself.
These possible adverse effects include oncogenicity,
mutagenicity, teratogenicity, persistence and bioaccumulation
in the aquatic environment, and avian reproduction.  The
request for these data is independent of the Agency's RPAR
determination.  The registrant is currently engaged in
discussions with the Agency concerning these data
requirements.

The Agency also determined that the risk to aquatic plants,
aquatic invertebrates, wildlife and fish from all uses of
oxyfluorfen could be reduced by labeling without adverse
impact on benefits.  For the soybean use, additional labeling
to protect certain species of endangered aquatic molluscs
from the possible hazard posed by the erosion of oxyfluorfen-
bound soil was proposed.  The registrant has subsequently
filed label amendments to include these changes.

The Scientific Advisory Panel and the United States Department
of Agriculture have both concurred on the proposed decision
in the PD 1/2/3.  Their comments on the auxiliary issues have
been addressed in the PD 4.

The Agency has decided that the final determination
regarding oxyfluorfen will remain unchanged from that
proposed in the PD 1/2/3.

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I. Introduction

Under the Federal Insecticide,  Fungicide,  and Rodenticide Act, as amended
(FIFRA)  (7 U.S.C. Section  136 et seoj  the  Environmental Protection Agency
(EPA or  the Agency) regulates all pesticide products.   Section 6(b) of FIFRA
authorizes the Administrator of the  EPA to issue a notice of intent to cancel
the registration of a pesticide or to  change its classification if it appears
to him that the  pesticide or its labeling "does not comply with the provisions
of [FIFRA] or, when used in accordance with widespread and commonly recognized
practice, generally causes unreasonable adverse effects on the environment"
Section  3(c)(6) authorizes the  Administrator to deny applications for
pesticide registration  if  the statutory standards for registration are not met.

The Agency designed the Rebuttable Presumption Against Registration (RPAR)
process  to gather risk  and benefit information about problem pesticides and to
make balanced decisions concerning them in a manner which allows all interested
groups to participate.  This process is set forth in 40 CFR 162.11.

      A. Summary of Position Document  1/2/3

Cxyfluorfen was referred to the Special Pesticide Review Division of the Office
of Pesticide Programs  in January of  1980 because pesticide products containing
oxyfluorfen as an active ingredient  are contaminated with perchloroethylene
(PCE).   PCE was demonstrated to be a liver carcinogen  in mice in a National
Cancer Institute  (NCI)  carcincgenicity bioassay (1977).  Because of the
carcinogenic potential  of  PCE shown  in the NCI study,  the Agency determined
that PCE-contaminated oxyfluorfen met  or exceeded the  rebuttable presumption
against  registration  (RPAR) criterion  for  oncogenicity as set forth in 40 CFR
162.11.

In the interest of achieving an expedited  review of the uses of oxyfluorfen,
the Agency decided to  issue a position document which  integrated the position
document 1 presumption  against  registration and the position document
2/3 risk/benefit analysis.  It  seemed  reasonable to focus public discussion on
the risk/benefit analysis  by presenting the Agency's proposed position in a
single document, the Position Document 1/2/3, (PD 1/2/3).

Currently, there is one registered product containing  the active ingredient
oxyfluorfen.  This product is marketed under the trade name Goal® 2E,
contains 23.5 percent oxyfluorfen, and, along with technical oxyfluorfen,is
manufactured solely by  the Rohm and  Haas Company of Philadelphia,  Pennsylvania.

At the initiation of this  review,  Goal® 2E had already been registered for use
on conifer seedbeds, transplants and outplantings,  and certain nonbearing tree
fruits/nuts in California; and  conditional registrations were pending for
soybeans, certain bearing  tree  fruits/nuts and field com.  The field corn use
applies only to those 38 counties in North and South Carolina which are part of
the U.S.  Department of  Agriculture Witchweed Eradication Program.  The
conditional registrations  were  subsequently granted in an action separate from
the PD 1/2/3,  with the  conditions  described in the PD  1/2/3.

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           1.  Risk

Based  upon "worst case"  exposure situations and the current maximum level  of
PCE  in formulated oxyfluorfen products (200 ppm), the Agency estimated  the
carcinogenic  risk associated with PCE-contaminated oxyfluorfen to both  the
agricultural  worker and  the general public.

The  carcinogenic risk associated with each of the uses of PCE--
contaminated  oxyfluorfen is presented in Table 1. These values show slightly
higher levels of risk than those presented in the PD 1/2/3.  This discrepancy
is discussed  further in  Section II of this document.

Five other areas of concern were also addressed in the PD 1/2/3, related to
oxyfluorfen itself.  The areas of concern were oncogenicity, mutagenicity,
teratogenicity,  and subchronic effects.  The potential for adverse
environmental effects was also examined in light of the pending registrations
for  the corn  and soybean uses. Valid data concerning the chronic toxicity  of
oxyfluorfen in the above-mentioned categories are necessary to support
registration  of all uses of oxyfluorfen.

           2.  Benefits

The  benefits  associated  with each use of oxyfluorfen were discussed at  length
in the PD 1/2/3.  In summary, the benefits of oxyfluorfen use include the
following.

     o     Oxyfluorfen possesses both pre- and post emergence activity.   This
          increases herbicide utility and allows for season-long control of
          certain weeds.

     o     Oxyfluorfen is  less dependent on soil and moisture conditions  than
          some otherwise  comparable herbicides.

     o     Oxyfluorfen appears to be uniquely effective for control of certain
          problem weeds (e.g. cheeseweed,  witchweed).

     o     Oxyfluorfen is  competitively priced with respect to other herbicides
          registered for  the same use pattern.

     o     Oxyfluorfen, when applied as directed, will not cause injury to
          conifers or crops specified on the label.

          3.   Risk/Benefit Analysis and Regulatory Options

The  Agency developed various regulatory options with respect to oxyfluorfen
products  and  has evaluated each option for its impact on risks and benefits.

The  regulatory options considered in the PD 1/2/3 for conclusion of the
oxyfluorfen RPAR focused on methods to reduce levels of human exposure  to  the
PCE  contaminant,  and to  reduce environmental risk associated with the uses  of
oxyfluorfen.


                                       -2-

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i
U)
I
                                             Table 1
      Carcinogenic Risk-'to Agricultural Workers and to  the General Population
      Associated with  the Use of PCE-'-Contaminated Oxyfluorfen.
      CROP           	RISK	
                              Worker~General  Public
                      (Inhalational  +  Dermal)-'                       (Dietary)

      Soybeans              4.20  x 10~6                           5.30  x 10~8
      Field Corn            1.10  x 10~4                           3.03  x 10"8
      Tree Fruits/Nuts      1.70  x 10~5                           1.00  x 10~6
      Conifers              1.80  x 10~5                               	
      a/ Based on multistage model.
      b/ Assumes 200 ppm  in formulated product.
      £/ Inhalation is  estimated  to  be the primary  route  of
      ~~  exposure.  See revised Table 4.

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The Agency considered the  following  six regulatory options.

         a. Specify a maximum PCE contamination level of 200 ppm in formulated
            oxyfluorfen products.

         b. Require protective equipment (suitable respirators) to be worn
            during the mixing, loading,  and  application of oxyfluorfen products.

         c. For the pending registration for soybean use, prohibit use of
            oxyfluorfen products in  counties providing habitat for endangered
            molluscs.

         d. Require labeling for the pending registration for soybean use in
            order to protect aquatic molluscs.

         e. Require labeling for all uses of oxyfluorfen for the protection of
            aquatic plants, aquatic  invertebrates,  wildlife and fish.

         f. Require development of certain data on the possible adverse effects
            of oxyfluorfen en man and  the environment to be submitted to the
            Agency by the  registrant.   The areas of concern for which the data
            would be required include:   oncogenicity, mutagenicity,
            teratogenicity, subchronic effects,  persistence and bioaccumulation
            in the environment, and  toxicity to fish and wildlife.

The risks and benefits for each use  were compared under each appropriate
option listed above.  This use-by-use  risk/benefit  analysis was detailed in the
PD 1/2/3.

         4.  Proposed Regulatory Decision

Based on the use-by-use risk/benefit analysis,  the  Agency proposed  the
following regulatory decision.

For all uses of oxyfluorfen products (currently registered and proposed) the
Agency proposed that:

    o    The PCE contamination of formulated oxyfluorfen products (Goal® 2E)
         may not exceed 200 ppm and  that a statement to that effect  be added to
         the confidential  statement  of  formula  for  each registered oxyfluorfen
         product.

    o    A pesticide respirator jointly approved by the Mining Enforcement and
         Safety Administration (formerly the U.S. Bureau of Mines) and by the
         National Institute for Occupational Safety and Health under the
         provisions of 30  CFR Part II  for perchloroethylene must be  used during
         the mixing, loading and application of  all oxyfluorfen products.
         Labelling of all oxyfluorfen products must be amended to include this
         statement.  This  requirement will take  effect six months after
         the date of publication of  the  Notice announcing the  final
         determination concluding the oxyfluorfen RPAR,  unless by that time  the
         registrant submits field monitoring  data to the  Agency establishing
         that the inhalational exposure  for  the  maximum application  rate for
         each  registered use is significantly lower than  the inhalational
         exposure estimated by the Agency.


                                         -4-

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    o     Labeling  for the protection of wetlands and other aquatic resources is
          required  as part of the conditions for registration.  Specific
          label  statements are to read as follows.

             For Soybeans:

             "This  product is highly toxic to freshwater clams, oysters, aquatic
             invertebrates and aquatic plants.  Do not apply where visible
             erosion to aquatic habitats and wetlands occurs."

             For all other uses;

             "This  pesticide is highly toxic to aquatic plants, aquatic
             invertebrates, wildlife and fish.  Use with care when applying
             in  areas frequented by wildlife or adjacent to any body of
             water  or wetland area.   Do not apply when weather conditions
             favor  drift or erosion from target area.  Do not contaminate
             water  bodies by cleaning of equipment or disposal of wastes."

The Agency also determined that with the adoption of the above-mentioned
provisions,  amending the existing Goal 2E registration to include use on
soybeans, field corn, and bearing tree fruits/nuts would not significantly
 increase the risk  of unreasonable adverse effects on man or the environment.
The Agency,  however, recommended that subsequent registrations for these
proposed uses (field com, soybeans, bearing tree fruits/nuts and any other
uses  to be proposed) include the following condition due to oxyfluorfen's
persistence  and potential to bioaccumulate.

          Extensive field monitoring for oxyfluorfen residues in each proposed
          use pattern area would be required.  The registrant would submit these
          data to the Agency within two years of the date of conditional
          registration.

The detailed rationale for the proposed decision is presented in the PD 1/2/3.
In summary,  those  options which would result in maximum risk reduction or
incremental  risk reduction with minimum impact on the benefits of oxyfluorfen
use.   During the course of this review the registrant reduced the PCE
contamination of oxyfluorfen from 1680 ppm to 200 ppm or less in the formulated
product.   The Agency based its risk assessment on the current level (200 ppm)
of PCE in oxyfluorfen and "worst case" exposure conditions.  Based on the
resulting "worst case" risk figures, the Agency determined that to allow PCE
levels higher than 200 ppm would increase the risk without a concomitant
increase  in  benefits.   Limiting PCE levels to 200 pcm would not affect the
benefits  adversely,  because oxyfluorfen is currently produced with levels of
200 ppm or less PCE.

The "worst case" exposure estimates resulted in risk estimates for
mixer/loader/applicators which the Agency believed warranted the use of
protective equipment.   Because inhalational exposure appears to be the major
component of  worker  risk,  respirators would be required unless actual
monitoring data submitted by the registrant demonstrate that exposure to PCE
during  application of  oxyfluorfen is significantly less than that estimated  by
the Agency.   This  course of action will reduce risk, not adversely affect the
benefits,  and provide  the registrant with the option of supplying additional
information  to  the Agency so that the risk assessment and consequently the
regulatory decision  may be modified as indicated by these data.


                                         -5-

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The environmental hazard labeling,  as  part of the conditions for registration,
is designed to reduce the possible  hazard to the environment, in particular to
aquatic habitats, without major  use restrictions.  For the soybean use pattern,
specific labeling has been developed.   This labeling has been coupled with a
requirement for extensive field  monitoring for oxyfluorfen residues.  If levels
in aquatic habitats are .found  in monitoring studies to approach toxic levels,
the Agency may reconsider the  option of restricting use of oxyfluorfen from
those counties providing habitat for endangered molluscs.  This monitoring
requirement has also been required  as  a condition of registration for the field
corn and tree fruit/nut uses.

In an action independent of  the  RPAR under authority of FXFPA section
3(c)(2)(B), the Agency stated  in the PD 1/2/3 that the registrant would be
required to submit the following oxyfluorfen studies to the Agency in support
of all registrations.

      o  The registrant is to  be required to submit to the Agency an
         oxyfluorfen teratogenicity study in rabbits.   The protocol of this
         study should include  post-natal evaluation and should be submitted
         before initiation of  testing.

      o  A battery of mutagenicity  tests are to be submitted to the
         Agency.  Protocols  should  be  submitted to the Agency prior to the
         initiation of testing.

      o  The registrant is to  be required to submit an oxyfluorfen oncogenicity
         study in mice and an  oxyfluorfen oncogenicity study in rats.
         Protocols for these studies are to be submitted prior to initiation
         of testing.

      o  The registrant is to  be required to submit a 6-month (or longer) dog
         feeding study which demonstrates a no-observed-effect level (NOEL).
         Protocols for this  study have been published in 43 FR 37536,
         August 22, 1978.

      o  The registrant is to  be required to submit avian reproduction studies
         with mallard ducks  and  bobwhite quail.

The registrant is currently  engaged in discussions with the Agency concerning
these proposed actions for testing  of  oxyfluorfen.  In the course of these
discussions, the Agency has  determined that the information needed to evaluate
the human health effects of  oxyfluorfen can be obtained without requiring the
registrant to perform all of the studies specifically detailed in the PD 1/2/3.
As a result of clarification of  data in the existing dog chronic feeding study,
the Agency has found the study demonstrates an acceptable no-observed-cffect
level and the registrant will  not be required to repeat the study.  The Agency
has also determined that, since  the acceptability of earlier rodent
oncogenicity studies hinges  on whether the highest experiment dose was near the
maximum tolerated dose (MTD),  the registrant will first conduct short-term
studies to determine the MTD.  Unless  this MTD is significantly higher than the
                                      -6-

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high dose in the earlier experiments,  the Agency will not require further
oncogenicity testing.  All proposed  testing requirements are currently under
discussion with the registrant.   Final determination of the studies to be
required will be made when discussions with the registrant are completed, and
the Agency will issue a letter to the  registrant, under authority of FIFRA
section 3(c)(2)(B), requesting the studies.  At that time, the Agency will
specify a value of the NOEL  for  teratogenicity data that indicates acceptable
safety, based on calculated  exposure and an adequate magin of safety.

     B.  Request for Comments

FIFRA requires the Agency to submit  notices issued pursuant to section 6 to the
Secretary of Agriculture for comment en the proposed action [section 6(b)]  and
to a Scientific Advisory Panel (SAP) for comment on the impact of the proposed
action en health and the environment [section 25(d)].  The Secretary of
Agriculture and SAP are invited  to comment, as required by the statute, in
writing within 30 days of receiving  the notice and the Agency is required to
publish their comments and the Administrator's response with publication of the
notice of final determination.

The Agency presented its proposed decision to the SAP at a public meeting held
on May 13 and 14, 1981.  Notice  of the meeting was published in the Federal
Register on April 27, 1981,  indicating the availability of the PD 1/2/3 and
describing the procedures for making oral and written comments.  In addition,
the SAP contacted, by mail,  members  of the general public who had previously
expressed an interest in the Panel's activities.   The SAP meeting was attended
by the registrant and other  interested parties.

The Agency has received three sets of  comments in response to the March, 1981,
Oxyfluorfen Position Document 1/2/3.   Responses from the SAP,  the U.S.
Department of Agriculture, and the registrant have been analyzed and are
addressed in Section III of  this document.  The responses from the SAP and  the
USDA are presented in Appendix B in  their entirety.
                                      -7-

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II. Revisions and Amendments  to PD 1/2/3 - Exposure and Risk

Since publication of  the  PD 1/2/3, the estimates of PCE exposure have been
revised.  Refinements in  calculation have demonstrated that exposure to PCE
from use of oxyfluorfen products had been underestimated by a factor of three
in the  initial review.  As  a  result, it was also necessary to revise the  risk
figures, which are  a  function of the exposure.

Tables  2 and 3 present  the  original and revised PCE exposure estimates for all
uses of oxyfluorfen.  Revised risk estimates are presented in Table 4.
All tables relating to  exposure and risk estimates which were presented in the
PD 1/2/3 have been  corrected  and the revised editions appear in Appendix  A of
this document.

From a  review of Tables 2,  3, and 4, of this docunent, the Agency concludes
that the revised risk figures are not significantly different from those  which
appear  in the PD 1/2/3.  However, the Agency wishes to present the most
accurate evaluation possible  in its final decision.  The Agency has determined
that these revisions  do not affect the proposed regulatory action.  The means
for reducing risk to  applicators have already been proposed, and these are
sufficient to take  into account the slightly higher revised risk figures.
                                         -8-

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                                            Table 2
                     Adjusted Lifetime Average Daily Worker .Exposure
                           to PCE-'from Use of Oxyfluorfen-'
10
I
Route
Crop
Exposure—'
(mg/kg/day)
Original
Inhalational-/


Dermal-

Total



Soybeans
Field corn
Tree fruits/nuts
Conifers
Soybeans
Field corn
Tree fruits/nuts
Conifers
Soybeans
Field corn
Tree fruits/nuts
Conifers
0.
7.
1.
1.
0.
20.
0.
1.
0.
7.
1.
1.
3
0
1
1
4
0
4
7
3
2
1
1
X
X
X
X
X
X
X
X
X
X
X
X
10
10
10
10
10
10
10
10
10
10
10
-4
-4
A
~
-6
-6
-6
-6
-4

_ »
10~"
0.
20.
3.
3.
1.
60.
1.
4.
0.
21.
3.
3.
Revised
8
6
3
3
2
0
3
8
8
0
3
4
X
X
X
X
X
X
X
X
X
X
X
X
10
10
10
10
10
10
10
10
10
10
10
-4
-4
-4
^t
~

-6
-6
-6
-4

_ *
10—
       a/ Assumes 200 ppm in formulated product.
       b/ Assumes exposure time of 10 days/year (62.5 days for corn),
          a working life of 40 years and a 70-year life span.
       c/ See Appendix A, Tables 2 and 3 for individual daily dermal and
       ~  inhalation figures.
       d/ Based on an 8-hour day of spraying.
       e/ Based on 1 hour mixing/loading and 7-hours spraying.

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                         Table 3

        Adjusted Maximum Dietary Exposure to
           PCE— 'from Uses of Oxyfluorfen


                                Exposure^'
Crop                           (mg/kg/day)

                     Original               Revised


Soybean              1.04 x 10~6            1.04 x 10~6

Field Corn           0.05 x 10"6            0.57 x 10"6

Tree Fruit/Nuts     19.00 x 10~6           19.00 x 10~6
a/ Assumes that 0,05 ppm level of analytical sensitivity is
   equivalent to 0.05 mg/kg of commodity.

b/ Daily consumption of commodity in mg/person/day based on
   average consumption figures for each commodity (U.S. EPA,
   1981, PD 1/2/3).

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                                   Table 4
    Carcinogenic Risk-/to Agricultural Workers and the General
    Public Associated with  the Uses of PCE-'-Contaminated Oxyflurofen
Crop
Risk Estimate
                          Original
a/ Uses multistage model  for calculations.

b/ Assumes 200 ppm PCE  in formulated product.

c/ Uses revised exposure  figures  from Tables 2 and  3,
                    Revised—'
                                                                          c/
WORKER:
Soybean
Field Corn
Tree Fruits/Nuts
Conifers
DIETARY:
Soybeans
Field Corn
Tree Fruits/Nuts

1.5 x 10"|
3.8 x 10~j?
5.8 x 10":!
5.8 x 10~b

5.30 x 10"?
2.65 x 10";:
1.00 x 10~b

4.2 x 10"^
1.1 x 10~J
1.7 x 10~j?
1.8 x 10"*

5.30 x 10~J
3.03 x 10"?
1.00 x 10"b

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III.  Analysis of  Garments

The Agency received  comments from the Secretary of Agriculture, the Scientific
Advisory Panel  (SAP)  and  the registrant.   These comments are organized by  topic
and discussed below.   As  indicated in the following discussion, the Agency has
revised some aspects  of its  assessment of risks, benefits, and regulatory
requirements in  accordance with USDA, SAP, and other recommendations.  Except
as discussed below and in Section II, other aspects of the analysis presented
in the Position  Document  1/2/3 are unchanged.

    A.  Comments Relating to Risk

The Agency has  received no comments on its assessment of the carcinogenic  risk
from PCE associated with  the uses of oxyfluorfen.  Minor revisions in exposure
and risk figures have been made by the Agency and have been presented and
discussed  in Section  II of this document.

The SAP has concurred with the Agency's assessment of risk from PCE but has
stated that it has "a number of serious concerns with oxyfluorfen not
related to the oncogenic  hazard from PCE«.." (30000/36:#3).  These concerns
relate to  the following issues.

         1. The  persistence  and possible bioaccumulation of oxyfluorfen
            in  the food chain.

         2. The  adequacy  of  testing of oxyfluorfen's potential teratological
            effects given its structural resemblance to nitrofen.

         3. The  identification and potential adverse effects of the various
            inert  ingredients in oxyfluorfen.

With regard to  issue  (1)  above, the Agency shares the SAP's concern regarding
the persistence  of oxyfluorfen in the environment. This concern was discussed
in the PD  1/2/3  and  the Agency has proposed that extensive field monitoring for
oxyfluorfen residues  in the  major use pattern areas be required as part of the
conditions for registration.  The field monitoring outlined by the Agency  in
the PD 1/2/3 includes provisions for evaluating the potential of oxyfluorfen  to
bioaccumulate in aquatic  organisms.

Issue number (2) pertains to oxyfluorfen's potential to cause teratogenic
effects.   This concern arises from the fact that oxyfluorfen is structurally
similar to nitrofen,  a known teratogen.  Therefore, the SAP believes that  an
especially careful evaluation of oxyfluorfen is warranted.

The Agency agrees  with the SAP that a special effort should be made to
determine  that no  teratological problem exists with oxyfluorfen.  The PD 1/2/3
discussed  the information available at the time and highlighted the need for
some further study.   Along with the rat teratology study submitted by the
registrant  (negative  for  teratogenic effects at 1000 mg/kg/day), the registrant
is currently conducting a second teratology study with rabbits which will be
submitted  in late  1981.   Additional teratogenic evaluation of oxyfluorfen  is
being conducted by EPA at its Research Triangle Park (RTP), N.C. facility.  The
EPA scientist in charge of this research has also evaluated the  teratogenic
effects of  nitrofen and acifluorfen (two diphenyl ethers similar to
                                        -12-

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oxyfluorfen).  Therefore,  any teratogenic effects of oxyfluorfen similar to
those of nitrofen should be recognized.  Also, the Agency points out  that
structurally similar  chemicals do not necessarily possess the same
toxicological characteristics.  Evidence of this in the case of diphenyl ethers
cones from the above-mentioned EPA studies being done at FTP.  Data from these
studies indicate  that nitrofen is teratogenic but that acifluorfen is negative
for teratogenic effects (Dykstra, 1981).

Following the evaluation of the rabbit teratology study, to be submitted in
late 1981 by the  registrant,  and the results of EPA testing of oxyfluorfen, the
Agency will then  determine whether further testing is warranted, or whether the
information to date is sufficient to accurately evaluate the teratogenic
potential of oxyfluorfen.

SAP's third concern relates to the level of impurities in technical oxyfluorfen
and the possible  adverse effects of these impurities on the environment.

Although not specifically  discussed in the PD 1/2/3, the identification of and
toxicological  information  on the impurities in technical oxyfluorfen have been
submitted to and  reviewed  by the Agency (Rohm and Haas, 1978; Perfetti,  1978;
and Dykstra, 1978).   Unless an impurity or inert ingredient of a pesticide is
judged  to pose an unreasonable adverse effect on man or the environment,  it is
illegal to disclose such product information in a public document.   The Agency
has addressed  the issue of the impurities in technical oxyfluorfen and the
relevant reviews  are  on file.   These reviews were provided to the SAP.  The
panel expressed their satisfaction with the adequacy of these reviews.

    B.  Comments  Relating  to Benefits

The only comments relating to oxyfluorfen benefits were received from USDA
(30000/36:#2).  Essentially,  the USDA concurs with the Agency assessment of
benefits and adds that oxyfluorfen is particularly beneficial for witchweed
control and use in forest  nurseries.  The Agency agrees and believes that the
benefits of oxyfluorfen for use in corn and forest nurseries have been
adequately discussed  in the PD 1/2/3.

    C.  Comments  Relating  to Regulatory Options - Respirator Requirement for
        Mixer/Loader/Applicators

The USDA (30000/36:#2)  has agreed with the Agency's proposal to require
respirators during the  mixing,  loading,  and application of oxyfluorfen
products.  The USDA commented,  however,  that this requirement does not take
into account different  methods  of application.   The USDA stated that in many
forest nurseries,  pesticides  are applied through automatic watering systems
which would result in little  or no applicator exposure.

In assessing applicator exposure to PCE from use of oxyfluorfen products, the
Agency assumed spray  application as indicated on the Goal© 2E conifer label.
The Goal® 2E label does not currently provide rates, metering instructions,
limitations, precautions D-r y-)f-r directions for use of Goal® 2E through
automatic watering systems.   As indicated in the PD 1/2/3, oxyfluorfen
performance and exposure data are extremely limited.
                                        -13-

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The USDA. also ccranented that use of  respirators in many areas of the United
States poses problems of discomfort  due  to heat and humidity and that in
certain high temperature situations  the  hazards associated with the use of
respirators may be more immediate  and dangerous than the hazard due to
pesticide exposure.  The USDfc, suggests that research is needed to devise
protective measures suitable for hot weather.

In the case of oxyfluorfen, inhalational exposure accounts for 98 percent or
more of the total applicator exposure to the PCE contaminant, according to
Agency estimates.  Reducing inhalational exposure is therefore the most
effective method of reducing total exposure of applicators to PCE in
oxyfluorfen.  Respirator use dramatically decreases total exposure and
resultant risk, as illustrated  in  revised Table 11.

The Agency recognizes the reluctance of  applicators to wear respirators in hot
and humid weather situations.   The Agency is not aware, however, of any data
which indicate that the use of  respirators in  high temperature situations
results in "more immediate and  dangerous hazards than exposure to the
chemical."

With respect to oxyfluorfen specifically,  the  Agency believes (as stated in the
PD 1/2/3) that its exposure estimates for applicators are, of necessity, "worst
case" values and has invited the registrant to submit data demonstrating that
actual exposure to PCE is significantly  lower  than Agency estimates.  These
data are not anticipated to be  costly to generate and could successfully rebut
the respirator requirement.  Until such  time as these data are available or
other protective methods are developed,  the Agency will require the currently
available means of reducing inhalational exposure (respirators)  to be used
during mixing, loading, and application  of oxyfluorfen products.

The registrant has also submitted  conroents (30000/36:#1)  on implementation of
the respirator requirement.  Rohm  and Haas believes that "the actual inhalation
exposure to PCE from Goal® formulations  is significantly less than that
calculated by the Agency and the company will  obtain actual field monitoring
data to substantiate its contention."

After reviewing comments frcm the  Departnent of Agriculture,  the Scientific
Advisory Panel, and the registrant on the  Agency's findings and recommendations
concerning oxyfluorfen as set forth  in the PD  1/2/3,  the Agency has decided to
implement its proposed decision without  modification.
                                        -14-

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                           Bibliography of Comments

FIFRA Scientific Advisory Panel.  June 19, 1981.  Gray, P.H.   (30000/36:#43).

Rohm and Haas Company.  May 11, 1981.  Krzemenski, S.F.  (30000/36:11).

USDA, United States Department of Agriculture.  July 6, 1981.  Flamm, B.R.
     (30000/36:ft2).

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                                  References

CFR, 40. 1980.  Protection of  the Environment.   Subchapter E—Pesticide
     Programs.  CFR 40, Part 162—Regulations  for the Enforcement of the
     Federal Insecticide, Fungicide  and  Rodenticide Pet.   Subpart A—
     Registration, Reregistration and Classification Procedures.   CFR 40,  Part
     162.11—Criteria for determinations of  unreasonable  adverse  effects.

Dykstra, W. 1981.  Personal ccnraunicaticn with  Neil Chernoff.   Concerning
     teratogenicity testing at Research,  Triangle Park,  N.C., May  6,  1981.

Dykstra, W. 1978.  Request for establishment of permanent tolerances on
     soybeans and corn at 0.05 ppm for oxyfluorfen and  its metabolites
     containing the diphenyl ether linkage.  Memo to Robert Taylor RD, OPP,
     OPTS, EPA.   November 7,  1978.

Federal Register. 1978. Proposed Guidelines  for Registering Pesticides in  the
     United States.  Federal Register Vol. 43 No.  132.  Pages 29709-10, July  10,
     1978.

Federal Register.  1978.  Proposed Guidelines  for Registering  Pesticides in  the
     United States.  Federal Register Vol. 43.  No.  163, Page 37536.   August  22,
     1978.

Federal Register.  1980.  Endangered and Threatened Wildlife and  Plants.
     Federal Register Vol. 45, No. 99. pg 33768,  May 20,  1980.

Federal Register.  1980.  Proposed Guidelines  for Mutagenicity Risk
     Assessments.  Federal Register  Vol.  45, No.  221, pg.  74984,  November  13,
     1980.

FIFRA. 1978. The Federal Insecticide, Fungicide and Rodenticide Act  as
     Amended.  Public Lavs 92-516, 94-140, 95-396.  7 U.S.C. 136 et seq

Hitch, R. 1981. Conditions to  the Registrations of Goal for PD 1/2/3.  EPA memo
     to J. Chinchilli, SPRD, OPP, OPTS,  EPA. January 12,  1981.

National Cancer Institute. 1977.  Bioassay of tetrachloroethylene for possible
     carcinogenicity.  Carcinogenesis Technical Report  Series  No. 13,
     NCI-CG-TR-13, DHEW Publication  No.  (NIH) 77-813.

Perfetti, R.B. 1978.  Oxyfluorfen on soybeans and corn.   Memo  to  R.  Taylor RD,
     OPP, OPTS, EPA.  July 12, 1978.

Rohm and Haas Co. 1978.  Petition for Establishment of  Permanent  Tolerances  for
     Goal® 2E on Soybeans and  Corn,  September 29,  1978.   Pesticide Petition
      8F2058, Ace. No. 097425.

U.S. Environmental Protection  Agency. 1981.  Oxyfluorfen (Goal  2E®) Position
     Document 1/2/3, Project Manager, Jolene Chinchilli.

Vilkas, A.G. 1978. Unpublished study done by Union Carbide Environmental
     Services for Rohm and Haas Co.  The acute  toxicity of RH  2915 to the
     Eastern Oyster, Crassostea virginica.   Ace. # 096881, July 1,  1978.
     (confidential)

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                APPENDIX A

Revised Exposure and Risk Tables from the
Oxyfluorfen Position Document 1/2/3
                  TABLE 2.

Daily PCE Inhalation Exposure for
Applicator/Mixer/Loaders Using Goal
CROP                     (mg/kg bw/day)



Soybeans                 5.282 x 10"3

Field Corn              21.127 x 10~3

Tree Fruits/Nuts        21.127 x 10~3

Conifers                21.127 x 10~3



a/ Assumes 200 ppm PCE in Goal 2E.

b/ Assumes an 8-hour day of spraying.

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                    TABLE 3.
        Daily PCE Dermal Exposure for    ...  .

 Applicator/Mixer/Loaders Using Goal 2E3-' —'£f
CROP                      (mg/kg bw/day)
                                  —4
Soybeans                 0.78 x 10



Field Corn               6.20 x 10~4



Tree Fruits/Nuts         0.83 x 10~4



Conifers                 3.10 x 10"4
a/ Assumes 200 ppm PCE in Goal 2E.



b/ Assumes 1-hour mixing/loading and 7-hour spraying,



c/ Based on Staiff, et al. (1975) work on paraquat.

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                                     TABLE 4.
               Adjusted Lifetime Average Daily Worker Exposure
                                                    '
                          to PCE from Use of Goal
Crop
Inhalation
mg/kg bw/day
     Dermal
   mg/kg bw/day
   Total
 mg/kg bw/day
Soybeans
0.8 x 10
                              -4
Field Corn    [1981]  20.6 x 10~4
Tree Fruit/Nuts

Conifer
3.3 x 10
                              -4
3.3 x 10
        -4
 1.2 x 10
                            -6
60.0 x 10

 1.3 x 10
                            -6
                            -6
 4.8 x 10
         -6
 0.8 x 10
                           -4
21.0 x 10

 3.3 x 10
                           -4
-4
 3.4 x 10
         -4
a/  Assumes 200 ppm PCE in Goal 2E.

b_/  Soybean, tree fruit/nuts, and conifer estimates are based on 10
    working days per year.  Field corn estimates were further adjusted
    to reflect the number of days that applicators are estimated (Petrie,
    1980c) to be treating field corn as part of the USDA Witchweed Eradication
    Program during 1981 (62.5 days).  It is estimated that 100,000 acres of
    field corn will be treated in 1981.

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                                     TABLE 5.
               Adjusted Lifetime Average Daily Worker Exposure        /
           to PCE from Use of Goal 2E - Protective Clothing Scenario—7
Inhalation
Crop mg/kg bw/day
Soybeans 0
Field Corn (1981] 0
Tree Fruit/Nuts 0
Conifer 0
Dermal Total
mg/kg bw/day mg/kg bw/day
1.8 x 10~7 1.8 x 10"7
88.0 x 10"7 88.0 x 10~7
1.9 x 10~7 1.9 x 10~7
7.0 x 10~7 7.0 x 10~7
a/  Assumes applicators wear protective clothing and suitable respirator,

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                           TABLE 9.
Carcinogenic Risk to Applicator/Mixer/Loaders  and  to the
General Population Associated with  the PCE  Contaminant
of Goal 2E (Dykstra, 198Ib)
Crop                Exposure Estimate    Risk Estimate
                    (mg/kg/day)
Worker;
   Soybeans         0.8 x 10"4            4.2 x 10~6
   Field Corn      21.0 x 10~4            1.1 x 10~4
   Tree Fruit/Nuts            .                     _
   (bearing;        3.3 x 10~4            1.7 x lO'3
   nonbearing)
   Conifers         3.4 x 10~4            1.8 x 10"5
Dietary;
   Soybeans         1.0 x 10~6            5.30 x 10"8
   Field Corn       5.7 x 10~7            3.03 x 10~8
   Tree Fruit/Nuts            _
   (bearing only)   1.9 x 10"3            1.00 x 10"b

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                                           TABLE  10.

                       Adjusted  Lifetime  Average  Daily Worker  Exposure to and
                             Associated Risk  from PCE in Goal-7
Inhalation Dermal Total Risk
Crop (mg/kg bw/day) (mg/kg bw/day) (mg/kg bw/day)
Soybeans 0
Field Corn 11981] 0
Tree Fruit/Nuts 0
Conifers 0
1.8 x 10~7 1.8 x 10~7 9.5 x 10~9
88.0 x 10~7 88.0 x 10"7 4.7 x 10~7
1.9 x 10~7 1.9 x 10~7 1.0 x 10"8
7.0 x 10~7 7.0 x 10~7 3.7 x 10~8
a/  Assumes applicators wear protective clothing and suitable  respirator.

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                         TABLE 11.

Comparison of Applicator Risk With and Without the Use of
                Protective Equipment
Crop
   Risk Without
Protective Equipment
                                              Risk When Protective
                                              Equipment is Employed
Soybeans
     4.2 x 10
             ~6
                                                   9.5 x 10
                                                           ~9
Field Corn   [1981]
     1.1 x 10
             ~4
                                                   4.7 x 10
                                                           ~7
Tree Fruit/Nuts
     1.7 x 10
             ~5
                                                   1.0 x 10
                                                           ~8
Conifers
     1.8 x 10
             ~5
                                                   3.7 x 10
                                                           ~8

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                The Following Tables and Sample Calculations Are
                Revisions of Appendix A of the Oxyfluorfen Position
                Document 1/2/3, pp. 96-101.
                Maximal PCE Applied Under Goal 2E Use Conditions-'
                                                                a/

Soybeans
Field Corn
Tree Fruit/Nuts
Conifers

Goal
Pounds
A.I.
per acre
0.5
2.0
2.0
2.0
Application Rate
(lb/A)
Gallons
GoalK2E
per acre
0.25
1.00
1.00
1.00

Perchlorethylene
lb/acre-/
0.00042
0.00167
0.00167
0.00167
gm/acre^'
0.19
0.76
0.76
0.76
a/ Rohm and Haas, 1978. p. 580 (modified).  Assumes 200 ppm PCE in GoalR2E.

b/ 8.34 Ib./gallon/acre x  2 x 10~4 = 1.67 x 10"3 Ib PCE/acre.

c/ 1.67 x 10~3 Ib PCE/acre x 454 gm/lb. = 0.76 gms PCE/acre.

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                         Goal 2E and PCE Spray Rates, by Crop—'
                                                             a/
Goal Spray Rate

Crop
Soybeans
Field
Tree Fruit/Nuts
Conifers
Volume
(gal. /acre)
20
10
75
20
Weight-/
(gm/acre)
7.57 x 104
3.79 x 104
2.84 x 105
7.57 x 104
PCE Spray Rate
Weight
(gm/acre)
0.19
0.76
0.76
0.76
Concentration
(gm/mg H2O)
2.51 x 10~6
20.05 x 10~6
2.68 x 10"6
10.04 x 10"6

(ppm)
2.5
20.1
2.7
10.0
a/ Rohm and Haas, 1978 (modified).  Assumes 200 ppm PCE in Goal 2B.



b/ 1 gallon of H2O weighs 8.34 pounds.

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2. Sample calculations  for  inhalational, dermal, dietary exposure estimates,


   Inhalational       grams PCE/acre x volume air inhaled/day-^
   Exposure  =                      	~~
   (soybeans)         volume of air/acre-/ x average body weight



                      0.19 gm PCE/acre x 14.400 liters/day x 1000 mg/gm


                      7.4 x 106 liters/acre x 70 kg body weight



                      5.282 x 10~3 mg/kg bw/day



a/ 1.8 m3 hr x 1000 1/m3 x 8 hr/day = 14.400 liters/day


b/ volume of air/acre = 6 ft x 43,560 ft2 acre x 28.3 I/ft3


                      = 7.4 x 106 liters of air/acre

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Dermal Exposure -   PCE concentrations  x diluted spray   x  weight per    x  percent Skin
(soybeans)          in diluted spray	contacting skin    pint of water    penetration
                                          average body weight



                    2.51 ug/q x 0.048 pintsa/ x 454 g/pint x O.la/ x 1 mg/1000 ug
                                                 70 kq bw
                    7.8 x 10 5 mg/kg bw/day
a/ Values for the amount of liquid contacting applicator's skin (0.048 pints) and
   percentage skin penetration (10%) were estimated by the registrant (Rohm and Haas,
   1978).

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                                  Appendix B

The comments of  the  Scientific  Advisory Panel and the United States Department
of Agriculture on  the  Preliminary Notice of Determination Concluding the
Rebuttal Presumption gainst Registration of Pesticide Containing Oxyfluorfen
are presented below  in their entirety.

          FEDERAL  INSECTICIDE,  FUNGICIDE, AND RODENTICIDE ACT (FIFRA)

                             SCIENTIFIC  ADVISORY PANEL

                 Review of Preliminary  Notice of Determination
                 Concluding  the Rebuttable Presumption Against
             Registration  (REAR)  of  Pesticide Products Containing
                              Cxyfluorfen (GOAL 2E)


The Federal Insecticide, Fungicide,  and Rodenticide  Act (FIFRA)  Scientific
Advisory Panel has completed review  of  plans by the  Environmental Protection
Agency (EPA) for initiation  of  regulatory action on  pesticide products
containing oxyfluorfen (GOAL 2E)  under  the provisions of Section 6(b)(2)  of
FIFRA, as amended.   The review  was completed in an open meeting  held in
Arlington, Virginia  on March 13-14,  1981.  The following Panel members were
present for the review:  Drs. Torgeson,  Doull,  Metcalf,  and Davies.

Maximum public participation was  encouraged for the  review.  Public notice of
the meeting was published in the  Federal Register on Wednesday,  April 27,
1981.  In addition,  telephone calls  were received from and mailings sent to the
general public who had previously expressed an interest in activities of the
Panel.

Written and oral statements  were  received from technical staff and
representatives of the Environmental Protection Agency.   A written statement
was received from  Rohm and Haas Company, the registrant for oxyfluorfen.
Company representatives also participated extensively in the discussion.

In consideration of  all matters brought out during the meeting and careful
review of all documents presented by the Agency and  other parties, the Panel
unanimously submits  the following report:

                       Scientific  Advisory Panel Report on
                             Oxyfluorfen (GOAL 2E)

The Panel concurs with  the Agency's  proposed decision to conclude the
Rebuttable Presumption Against  Registration (RPAR) of Oxyfluorfen (GOAL 2E)
on the grounds that  the oncogenic hazard from perchloroethylene  (PCE) contained
in the compound  is no  longer sufficient to warrant the denial of a conditional
registration for various uses.

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However, the Panel has a number of serious  concerns  with oxyfluorfen not
related to the oncogenic hazard of PCE and  wishes  to bring these to the
attention of the Agency.  These concerns are:

1. The persistence of oxyfluorfen and its possible bio-magnification in the
   food chain*  This concern is based on Japanese  data on related compound's"
   which indicate a bioaccumulation effect.

2. The adequacy of testing of oxyfluorfen's potential teratological effects.
   The Panel expresses the belief that it is necessary to make  special efforts
   to determine that no teratological problems exists with all  the diphenyl
   ether class of chemicals.  The Panel thus recommends that additional
   teratological testing be conducted, with e.g. nitrofen being used for a
   positive control as a comparison.

3. The identification of the various inert  ingredients in oxyfluorfen and
   their potential adverse effects on the environment.   The Panel  notes that
   there is an impurities level of 28 percent in oxyfluorfen technical
   material, and states its belief that considerably more information is
   needed on the potential effects of these impurities.

    The Panel further notes that although oxyfluorfen  is intended  initially as
    a specialty herbicide with relatively low usage planned, nonetheless,
    the potential exists for much greater use, e.g.  as a replacement for
    nitrofen,  and therefore one must be concerned over potential health effects
    on a broader scale.

    In conclusion, the Panel reconmends that monitoring studies be  designed
    and carried out in order to clarify any adverse environmental effects of
    the use of oxyfluorfen.

    FCR THE CHAIRMAN:

    Certified as an accurate Report of Findings:
    Philip H. Gray, Jr.
    Executive Secretary
    FIFRA Scientific Advisory Panel

    DATE: June 19, 1981

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                                         July  6,  1981

Mr. Edwin L. Johnson  (TS-766C)
Acting Deputy Administrator  for
     Pesticide Programs
U. S. Environmental Protection Agency
Washington, D. C. 20460

Dear Ed:

This is the U. S. Department of Agriculture's  response  to
the U. S. Environmental Protection Agency's  (EPA) Preliminary
Notice of Determination Concluding the Rebuttable Presumption
Against Registration of the pesticide chemical oxyfluorfen
(GOAL).

We concur with the Agency's conclusions that the benefits
from the use of this chemical are biologically and economically
meaningful to agricultural production.  We have used Goal in
our witchweed program over the past three years.  Where it
has been used, control of witchweed has been excellent
lasting from six weeks to full season without observable
adverse effects on corn or other aspects of the environment.
Goal is rated as the best of the new herbicides for use in
forest nurseries. The indications are that it will become a
very important tool because it can be applied over the  top
of five-week old seedlings without any noticeable phytotoxicity
and because of the season-long control the material provides.

We agree with the requirement to use a respirator during the
mixing, loading and application of oxyfluorfen until the
registrant can more accurately assess inhalation exposure;
however, we are concerned that the requirement for respirators
makes no differentiation between methods of application.  In
many forest nurseries, pesticides are applied through
automatic watering systems which would result in little or
no applicator exposure.  In less sophisticated nurseries the
material is applied with a directed spray which should
result in low inhalation exposure.  We are hopeful that the
additional toxicology studies that the agency has requested
from the registrant will demonstrate that the use of respirators
is not necessary.  If it is determined that the use of
respirators is necessary, we suggest that consideration be
given to evaluating protective equipment that poses minimal
discomfort in hot, humid climate.  As we have pointed out in
the past, the use of respirators in many areas of the U. S.
poses problems of discomfort due to heat and humidity.
In these climatic conditions applicators and other support
personnel are often reluctant to use them, regardless of
regulatory requirements.  It has been suggested that in
certain high temperature situations the hazards associated
with the use of respirators may be more immediate and
dangerous than the hazard due to chemical exposure which the
use is intended to prevent.

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We would recommend followup action that would substantiate
that respirators significantly lower exposure during application
and that they are mitigating the problem.  Research is
needed to devise protective measures suitable for hot
weather.

If we can be of assistance in developing needed exposure
data, please advise.

Sincerely,
Barry R. Flamm
Director

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