United States
                  Environmental Protection
                  Agency	
                       Office of Prevention, Pesticides
                       And Toxic Substances
                       (7508W)	
EPA-738-F-92-012
September 1992
                  R.E.D.   FACTS
     Pesticide
Registration
    Use Profile
    Regulatory
        History
                  Ethylene
     All pesticides sold or used in the United States must be registered by
EPA, based on scientific studies showing that they can be used without
posing unreasonable risks to people or the environment. Because of
advances in scientific knowledge, the law requires that pesticides which
were first registered years ago be reregistered to ensure that they meet
today's more stringent standards.
     In evaluating pesticides for reregistration, EPA obtains and reviews a
complete set of studies from pesticide producers, describing the human
health and environmental effects of each pesticide.  The Agency imposes
any regulatory controls that are needed to effectively manage each
pesticide's risks.  EPA then reregisters pesticides that can be used without
posing undue hazards to human health or the environment.
     When a pesticide is eligible for reregistration, EPA announces this and
explains why in a Reregistration Eligibility Document, or RED.  This fact
sheet summarizes the information in the RED for ethylene.

     The pesticide ethylene is registered for use as a plant growth regulator
and a herbicide. Ethylene is used commercially as a ripening agent for
fruits and vegetables, a curing agent for tobacco, and  a flower-producing
agent in pineapples. It also is used to control witchweed in corn,  cotton,
peanuts and soybeans.

     The first pesticide product containing ethylene as an  active ingredient
was registered in December 1971.  In May 1990, EPA designated ethylene
as a biorational pesticide because it is naturally occurring and has a nontoxic
mode of action in controlling target pests.  Currently,  eight pesticide
products  containing ethylene are registered with EPA.
     Ethylene is exempt from the requirement  of a tolerance (or maximum
residue level) when used as a plant growth regulator on fruit and vegetable
crops, or when injected into the soil to cause premature germination of
witchweed, as part of the U.S. Department of Agriculture  (USDA)
witchweed control program. (Please see 40 CFR 180.1016.)

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 Human Health
   Assessment
Environmental
   Assessment
Toxicity
     EPA used information from the published literature rather than
requiring new studies from registrants to assess the toxicity of ethylene.
     Ethylene is a gas; therefore, the only exposure of toxicological
concern is exposure to the lungs.  Ethylene is naturally occurring and has
been used widely as an anesthetic since  1923 without reports of significant
toxicity. Therefore, EPA concludes that ethylene will be nontoxic to
humans under its approved conditions of use as a plant growth regulator and
in witchweed control programs.
Dietary Exposure
     Ethylene is exempt from tolerance requirements, as mentioned earlier.
EPA is requiring no residue data for reregistration because ethylene poses
no dietary risk concerns.
Occupational and Residential Exposure
     EPA has waived  requirements for applicator and residential exposure
studies because  ethylene poses no mammalian toxicity concerns.  In
addition, due to its high volatility, people are not likely to be exposed to
ethylene once it has been applied to fruit, vegetables or soil.
Human Risk Assessment
     The potential risks to people from the pesticide uses of ethylene are
considered negligible because ethylene is of low toxicity, high volatility (so
exposure to treated foliage and  foods as well as skin and lungs is minimal),
and has had years of safe use as an anesthetic.

Environmental Fate
     Since ethylene is a biorational pesticide, environmental fate studies
would not be required  unless adverse effects on fish and wildlife were noted
in ecological effects studies.  As explained below, all  ecotoxicity studies
have been waived.  Therefore, environmental fate studies are not required.
Ecological Effects
     EPA has waived  the ecological effects data requirements for both the
indoor and outdoor uses of ethylene. Because it is a volatile gas, ethylene
used indoors is not likely to result in exposure to nontarget species.  The
outdoor uses, soil injection and pineapple sprays, will result in only
negligible exposure to  aquatic and terrestrial organisms. Ethylene is
naturally occurring and of low toxicity.  Therefore, no data are required for
reregistration of the outdoor uses.
                    Environmental and Ecological Risk Assessment

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                               Ethylene is a naturally occurring, volatile gas, regarded as a
                         biorational pesticide due to its low toxicity.  Therefore, EPA finds that the
                         registered uses of ethylene do not pose an unreasonable risk to the
                         environment.

    Additional Data        EPA has waived all generic (that is, active ingredient- specific) data
            RedUJr0d  requirements for  ethylene except for technical chemistry studies, which have
                         been received and reviewed.

  Product LabGling        The labels of all registered ethylene products must comply with EPA's
ChanCieS ReQUired  current pesticide  labeling requirements.  A summary of the label
                         additions/changes required for ethylene technical or manufacturing use
                         products appears  in the RED.
                               The following  additions/changes are required in the  labeling of
                         ethylene end-use  products:
                               •  The signal word is "DANGER".
                               •  The Precautionary Statement must read,  "Liquefied or pressurized
                               gas can  cause frost burns.  Do not get in eyes or on  skin. Wear long-
                               sleeved shirt, long pants, boots,  goggles and chemical-resistant gloves
                               while handling cylinders or any  application equipment under pressure.
                               Harmful if  inhaled.  Avoid breathing vapors.  Do not enter
                               unventilated treatment areas unless wearing a respirator approved by
                               NIOSH/MSHA for this use."
                               •  The First Aid Statement of Practical Treatment must read, "IF IN
                               EYES:  Flush  with plenty of water.  Call a physician."
                               "IF ON SKIN: Wash with plenty of soap and water. Get medical
                               attention."
                               "IF INHALED:  Remove victim to fresh air. If not breathing, give
                               artificial respiration, preferably  mouth-to-mouth. Get medical
                               attention."
                               •  The Physical or Chemical Hazards Statement must read,
                               "Extremely flammable.  Contents under pressure. Keep away from
                               fire,  sparks and heated surfaces. Do not puncture or incinerate
                               container.   Exposure to temperatures above 130 degrees Fahrenheit
                               may  cause bursting."

         RGgulatory        *  All registered pesticide products containing the active  ingredient
         Conclusion  ethylene are not likely to cause unreasonable adverse effects in  people or the
                         environment,  and are eligible for reregistration. These products will be
                         reregistered once the required confidential statement of formula and revised
                         labeling are received and accepted by  EPA.

            For More        EPA is requesting public comments on the Reregistration Eligibility
                         Document (RED) for ethylene during  a 60-day time period, as announced in

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Information   a Notice of Availability published in the Federal Register.  To obtain a copy
                 of the RED or to submit written comments, please contact the Public
                 Response and Program Resources Branch, Field Operations Division
                 (7506C), Office of Pesticide Programs (OPP),  US EPA, Washington, DC
                 20460,  telephone 703-305-5805.
                      In the future, the ethylene RED will be available from the National
                 Technical Information Service (NTIS), 5285 Port Royal Road, Springfield,
                 VA 22161, telephone 703-487-4650.
                      For more information about ethylene or about EPA's pesticide
                 reregistration program, please contact the Special Review and Reregistration
                 Division (7508W), OPP, US EPA, Washington, DC 20460, telephone 703-
                 308-8000. For information about reregistration of individual ethylene
                 products, please contact PM Team 22, Registration Division (7505C),
                 OPP, US EPA, Washington, DC 20460, telephone 703-305-5540.
                      For information about the health effects of pesticides, or for assistance
                 in recognizing and managing pesticide poisoning symptoms, please contact
                 the National Pesticides Telecommunications Network (NPTN).  Call toll-
                 free 1-800-858-7378, 24 hours a day, seven days a week, or fax your
                 inquiry to 806-743-3094.

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