United States
                  Environmental Protection
                       Prevention, Pesticides
                       And Toxic Substances
May 1996
                  R.E.D.   FACTS
    Use Profile
     All pesticides sold or distributed 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 before November 1, 1984, be
reregistered to ensure that they meet today's more stringent standards.
     In evaluating pesticides for reregi strati on, EPA obtains and reviews a
complete set of studies from pesticide producers, describing the human
health and environmental effects of each pesticide. The Agency develops
any mitigation measures or regulatory controls needed to effectively reduce
each pesticide's risks. EPA then reregisters pesticides that can be used
without posing unreasonable risks to human health or the environment.
     When a pesticide is eligible for reregi strati on, EPA explains the basis
for its decision in a Reregistration Eligibility Decision (RED) document.
This fact sheet summarizes the information in the RED document for
reregi strati on case 3138, furanone.

     Dihydro-5-pentyl-2(3H)-furanone and dihydro-5-heptyl-2(3H)-
furanone (also known as gamma-nonalactone and gamma-undeccalactone,
respectively) are also referred to by the common name furanone. Products
containing furanones are registered for use as insecticides, insect and
mammal repellents, and mosquito larvicides.
     Pesticide products containing furanones may be used used as a dog
and cat repellent; fly, cockroach and ant killer; insect repellent, insect
repellent strip, and insect repellent tablecloth; and mosquito larvicide.
Formulations include liquid ready-to-use solutions, emulsifiable
concentrates, granulars and impregnated material.
     Furanone is applied by the use of impregnated table cloths,
premoistened applicator puffs, aersol sprayers, non-aerosol hand pump
sprayer, knapsack sprayers, and granules which may be applied by hand.
     Use practice limitations include a label statement prohibiting
application directly to treated, finished drinking water reservoirs or drinking
water receptacles. Users also must avoid application to man-made surfaces
sensitive to mineral oils.

     Furanone was first registered as a pesticide in the U.S. in 1983 for use
as a cat repellent.  Currently, there are seven furanone products, which are
registered as mixtures with the active ingredient, limonene (Case 3083).
The Agency issued a Reregistered Eligibility Decision (RED) on limonene
in September 1994. One of the seven products also contains a third active
ingredient, Aliphatic Petroleum Hydrocarbons.
Human Health
     Acute oral, dermal and inhalation toxicity studies indicate low acute
toxicity (Category IV). Likewise, eye and dermal irritation studies also
classified the formulated product in Category IV.  The product is not a skin
sensitizer.  Data from the open literature on each of the two compounds
considered the furanones to be of low toxicity.
     An open literature study provided useful information in evaluating the
potential hazard of the furanones, indicating that compounds making up the
furanones  did not demonstrate a hazard following subchronic and chronic
oral administration.
     The Agency usually would require a 90-day dermal toxicity study for
a product that may result in prolonged human dermal exposure through
repeated skin applications.  The Agency has decided to waive this
requirement for the furanones based on a combination of the following:
low exposure to furanones in the product; comparable concentrations of
tanols in this product to those already used in cosmetic products (lotions,
detergents, perfumes); a naturally occurring compound; and absence of
toxicity in the toxicology studies (notwithstanding limited data).
Dietary Exposure
     Currently registered pesticide products containing furanones have no
food uses so dietary exposure is not anticipated.  Although it is not a
chemical that is Generally Recognized as Safe (GRAS) by the Food and
Drug Administration (FDA), furanone is approved by FDA as a food
additive, and exposures to low concentrations are considered safe.
Occupational and Residential Exposure
     For the following reasons, the Agency has no concerns regarding
occupational or residential exposure to the furanones:  (1) all acute studies
for the furanones indicate that they have low acute toxicity (category IV);
and (2) the furanones are only in pesticide products that also contain
limonene,  and the percentage of furanones in these formulations is very
lowóless than 1%.
Human Risk Assessment
     The Agency does not anticipate occupational or residential risks of
concern from exposure to the furanones.  However, as the furanones are
only in pesticide products that also contain limonene, the following
concerns from the limonene RED apply to the furanones.

     Human exposure to furanones/limonene may occur during application
of animal repellent granules or insect spray, or use of impregnated
tablecloths.  Toxicological concerns for humans from exposure to limonene
include dermal irritation and sensitization.  Systemic toxicity is not
anticipated to occur at doses below the threshold for dermal irritation.
Ocular irritation also may occur if products are accidently placed in the eye
and not washed away.
     The tablecloth insect repellent product containing limonene was
exempted from tolerance requirements and is not believed to cause
exposure through food.  Exposure to limonene would be discontinued by
most users if dermal irritation occurred, and exposure therefore is believed
to be self-limiting. Product  labeling required by the limonene RED is
intended to prevent risks of potential skin and eye irritation to users.

Environmental  Fate
     Environmental fate data are not required to support the low-volume,
outdoor, residential uses of the furanones.  However, environmental fate
data generally are required to support aquatic nonfood uses such as the
mosquito larvicide use.  A quantitative environmental fate assessment
cannot be made for the furanones at this time because no environmental fate
data have been submitted for review. The furanones are classified as
lactones, and some open literature data are available on physiochemical
properties of lactones and their possible effect on the environment.  The
reported data indicate lactones may not be  stable in alkaline environments.
Ecological Effects
     Acute toxicity data indicate that the formulated product is practically
non-toxic on an acute oral and subacute dietary basis to birds, mammals,
and freshwater fish. The product is slightly toxic to freshwater
Ecological Effects Risk Assessment
     The furanones, when used as mosquito larvicides, are applied directly
to water.  The public health larvicidal use of furanones applied at
4.10 Ibs/acre (A) to 6  inches of water results in exceedances of the level of
concern (LOG) for freshwater invertebrates. The LOG for endangered
species is exceeded when the product is applied at 1.64 Ibs/A in water 6
inches deep or less, or when it is applied at 4.10 Ibs/A in water 1 foot deep
or less.
     This assessment is based on testing done on a formulated product and
tells little about the actual toxicity of the furanones as active ingredients.
Chronic invertebrate toxicity data and  basic environmental fata data would
improve the  Agency's understanding and assessment of the potential risk
posed by the use  of the furanones in mosquito larvicides.

    Risk Mitigation
     The volume of products containing furanones that are used annually
as mosquito larvicides is low, and the percentage of furanone in the
products is also low. The low volume and low percent of furanone support
the conclusion that widespread adverse impacts are not likely to result from
the mosquito larvicide use if continued at the amounts currently produced
and used.
     It should be recognized that the risk posed to aquatic invertebrates is
common to most, if not all, products registered for mosquito larvicide use.
It is the nature of these products to be harmful to aquatic invertebrates
because the target species is itself an aquatic invertebrate.  The mosquito
larvicide product containing furanones would cause less harm to aquatic
ecosystems than many other products because its risk is limited to aquatic
invertebrates, whereas others pose a risk to fish and birds, as well.

     To lessen the risks to aquatic invertebrates posed by furanones used
as mosquito larvicides, EPA is imposing a production limit on furanone for
use in mosquito larvicides of 150 gallons per year. Should the volume
produced and used and/or the percent of furanone in the product
significantly increase, the Agency would impose the following additional
data requirements to understand and assess potential risks:
   Additional Data
           161-1, Hydrolysis
           161-2, Photodegradation in Water
           162-3, Anaerobic Aquatic Metabolism
           162-4, Aerobic Aquatic Metabolism
           163-1, Leaching/Adsorption-Desorption
           164-2, Aquatic Field Dissipation

     EPA is requiring the following additional generic study for furanone
to confirm its regulatory assessments and conclusions:

           72-4(b), Life Cycle Invertebrate
                              The Agency also is requiring product-specific data including product
                         chemistry and acute toxicity studies, revised Confidential Statements of
                         Formula (CSFs), and revised labeling for reregi strati on.

 Product Labeling        All furanone end-use products must comply with EPA's current
            Changes   pesticide product labeling requirements and with the following. For a
Red III red              comprehensive list of labeling requirements, please see the furanone RED

                      The manufacturing use product (MP) labeling must be revised to
                 comply will all current EPA regulations, PR Notices and applicable
                 policies. The MP labeling must bear the following statement under
                 Direction For Use:
                      "Only for formulation into an [fill blank with Insecticide, Herbicide
                      or the applicable term which describes the type of pesticide use(s)]
                      for the following use(s)[fill blank only with those uses that are being
                      supported by the MP registrant."
                 An MP registrant may, at his/her discretion, add one of the following
                 statements to an MP label under

                      "Directions for Use" to permit the reformulation of the product for a
                      specific use or all additional uses supported by a formulation or user

                 (a)   "This product may be used to formulate products for specific use(s)
                      not listed on the MP label if the formulator, user group, or grower
                      has complied with U.S. EPA submission requirements regarding
                      support of such use(s)."
                 (b)   "This product may be used to formulate products for any additional
                      use(s) not listed on the MP label if the formulator, user group,  or
                      grower has complied with U.S. EPA submission requirements
                      regarding support of such use(s)."

                 End-use products without the mosquito larvicide use must bear the
                 following statement:

                           "Do not apply directly to water, or to areas where surface
                           water is present or to interidal areas below the  mean high-water
                           mark. Do not contaminate water when disposing of equipment
                           washwater or rinsate."
     The use of currently registered products containing furanone in
accordance with approved labeling will not pose unreasonable risks or
adverse effects to humans or the environment.  Therefore, all furanone
products for all uses are eligible for reregi strati on.
     These products will be reregistered once the required product-specific
data, revised Confidential Statements of Formula, and revised labeling are
received and accepted by EPA. Products that contain active ingredients in

                 addition to furanone and limonene will be reregistered when their other
                 active ingredients also are eligible for reregi strati on.
                      Environmental fate and chronic invertebrate toxicity data are not
                 available and are needed to complete the assessment of risks posed by the
                 use of the furanones as mosquito larvicides. However, EPA is not requiring
                 additional data as long as the production of furanone for this use does not
                 exceed  150 gallons per year.  Should the volume produced and used and/or
                 the percent of active ingredient in the product significantly increase, the
                 Agency may impose additional data requirements in order to develop a
                 more complete data base regarding these uses of furanone.

   For More        EPA is requesting public comments on the Reregi strati on Eligibility
Information   Decision (RED) document for furanone during a 60-day time period, as
                 announced in a Notice of Availability published in the Federal Register. To
                 obtain a copy of the RED document or to submit written comments, please
                 contact the Pesticide Docket, Public Response and Program Resources
                 Branch, Field Operations Division (7506C), Office of Pesticide Programs
                 (OPP),  US EPA, Washington, DC 20460, telephone
                      Electronic copies of the RED and this fact sheet can be downloaded
                 from the Pesticide Special Review and Reregi strati on Information System
                 at 703-308-7224.  They also are available on the Internet on EPA's gopher
                 server, GOPHER.EPA.GOV, or using ftp on FTP.EPA.GOV, or using
                 WWW  (World Wide Web) on WWW.EPA.GOV.
                      Printed copies of the RED and fact sheet can be obtained from EPA's
                 National Center for Environmental Publications and Information
                 (EPA/NCEPI), PO Box 42419,  Cincinnati,  OH  45242-0419, telephone
                 513-489-8190, fax 513-489-8695.
                      Following the comment period, the furanone RED document also 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 EPA's pesticide reregi strati on program,
                 the furanone RED, or reregi strati on of individual products containing
                 furanone,  please contact the Special Review and Reregi strati on Division
                 (7508W), OPP, US EPA, Washington, DC 20460, telephone
                      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, between 9:30 am and 7:30 pm Eastern Standard
                 Time, Monday through Friday.