United States
Environmental Protection
Agency
Offico of Pesticides anc
Office of Pestiaaa Prix
Washington, DC 2O46C
&EPA Pesticide
Name of Chemical: Mevinphos
Reason for Issuance: issuance of Rec
Date Issued: MARCH 31, 1988
Fact Sheet Number: 156
xic Substance*
i (TS-766C)
tration Standard
DESCRIPTION OF CHEMICAL
Generic Name: 3-[(Dimethoxyphosphinyl)oxy]-2-butenoic id methyl ester;
3-hydroxycrotonic acid methyl ester dime yl phosphate.
Common Name: Mevinphos
Trade and Other Names: Apavinphos, Duraphos, Menite, 'vinox, OS-2046,
Phosdrin, and Phosfene
EPA Shaughnessy Code: 015801
Chemical Abstracts Service (CAS) Number: 7786-34-7
ENT Registry Number: 22374
Year of Initial Registration: early 1950s
Pesticide Type: Insecticide
Chemical Family: Organophosphate
U.S. and Foreign Producers: E. I. DuPont (U.S.); Arrive Chemical Corp.
(U.S.); APA Spa (Ital. . Comlets Chemical
Industrial Co., Ltd (Taiwan); GEMP
International Corp. (Tai i); KenoGard VT AB
(Sweden); and Shell Int national Chemical
Co., Ltd. (England)
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2. PHYSICAL AND CHEMICAL CHARACTERISTICS
Chemical Characteristics of the Technical Material
Physical State: Liquid.
Color: Light yellow to orange.
Odor: Mild to none.
Molecular Weight and Formula: 224.1 — C 7 H 13 0 6 P.
Boiling Point: 99 - 103°C at 0.03 m Hg.
Vapor Pressure: 0.003 mm Hg at 21°C.
Density: 1.24 at 16°C.
Solubility in various solvents: Miscible with water, acetone, benzene,
carbon tetrachioride, chloroform,
ethanol, isopropanol, methanol, toluene,
and xylene; slightly soluble in carbon
disulfide and kerosene; insoluble in
hexane.
Physiological and Bi ochemical Characterl sti Cs
Mechanism of Pesticidal Action: Cholinesterase inhibition following contact
with, or ingestion of, mevinphos treated
surfaces.
Metabolism and Persistence in Plants and Animals: The metabolism of
mevi nphos in plants and ani nal s is not
adequately understood. The available plant
metabolism data indicate that mevinphos is
absorbed by plant roots, translocated readily
to leaves and growing shoots, and is degraaed
rapidly. The major residues identified in
plants are the alpha and beta isomers of
mevinphos and dimethyl phosphate. Mevinphos
acid is a minor metabolite in plants and it
has been demonstrated that mevinphos acid is
converted to desmethyl mevinphos acid. It has
been suggested that the end products of
mevinphos metabolism are methanol, acetone,
and carbon dioxide. The available animal
metabolism data indicate that twelve hours
after dosing 57 to 65% of the 32 P-residues was
excreted in the urine and feces (45 to 5O in
urine; 12 to 15 in feces). Only e’iinphos
hyth-oiysis products were present.
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3. USE PATTERNS AND FORMULATIONS
Application Sites: Alfalfa, anise (fennel), apples, artichoke, beans, beets
(including tops), Bermudagrass (seed crop), birdsfoot
trefoil, broccoli, broccoli raab, Brussels sprouts,
cabbage, carrots, cauliflower, celery, cherries (sour),
Chinese broccoli (gai lan), Chinese cabbage (including
napa or nappa cabbage, bok choy, pak choi, gai choy, and
mizunal), clover, collards, corn, cucumbers, eggplant,
grapes, grapefruit, kale, lemons, lettuce, melons
(including cantaloupes, honeydew melons, muskmelons, and
watermelons), mint, mustard greens, okra, onions
(including green onions), oranges, peaches, pears, peas,
peppers, plums, potatoes, raspberries, red chicory [ also
known as radicchio] (tops), sesame (seed crop), sorghum,
spinach, squash (summer), strawberries, tomatoes,
turnips (including tops), walnuts, ornamental flowering
plants, greenhouse agricultural crops (lettuce),
watercress, and sewage disposal plants.
Types and Methods of Application: Foliar application using conventional
ground or aerial equipment. Water
treatments are permitted in sewage
disposal plants
Application Rates: Recomended application rates range from 0.125 to 3.0
pounds of active ingredient per acre.
Types of Formulations: Dust, emulsifiable concentrates, soluble
concentrate/liquid, and ready to use.
4. SCIENCE FINDINGS
Summary Science Statement
Mevinphos is an organophosphorus compound and is a potent cholinesterase
inhibitor. The Agency has virtually no acceptable toxicity data for
mevinphos. However, a high incidence of physician—treated poisonings and
hospitalizations due to mevinphos have been noted. Poisoning Reports from
California indicate that mevinphos was among the top five pesticides
causing occupational poisoning in that state during 1981-1985. The major
routes of applicator exposure are through dermal exposure, with some
inhalation exposure. Results of a preliminary review of recently received
studies are consistent with a Toxicity Category I classification for acute
oral and acute dermal toxicity for mevinphos. Iievinphos was not teratogenic
in rats at a maternally toxic dose. Data gaps exist for acute toxicity,
subchronic effects, chronic feeding, oncogenicity, reproduction,
mutagenicity, and metabolic effects. A partial data gap exists for
teratogenicity. Flevinphos is very mobile in sandy loan, silt loan, loam,
and clay loam soils, ho’iever, insufricient data are available for the Agency
to fully assess the environnental fate of the conoound. Tolerances have
been established for a nwiber of raw agricultural conmodities, ‘iciever
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additional data are required to support many of them. The Agency has
insufficient data to establish an Acceptable Daily Intake (Aol) for
mevinphos at this time. Available ecological effects data show that
mevinphos is very highly toxic to aquatic organisms and birds. However, no
documented field kills of fish or birds have been noted. Because of its
demonstrated toxicity to nontarget species and its intended use pattern,
mevinphos has been identified by the Office of Endangered Species (OES),
U.S. Fish and Wildlife Service (FWS), as being likely to jeopardize
endangered species when used on corn and sorghum. Based on this
determination, OES specified reasonable and prudent alternatives to avoid
jeopardizing the continued existence of the identified species by these
uses. EPA is developing a program to reduce or eliminate exposure to these
species to a point where use does not result in jeopardy, and will issue
notice of any necessary labeling revisions when the program is developed.
Toxicology Characteristics
Except for a teratology study conducted in the rat, the Agency has no
acceptable toxicology data for mevinphos. In the rat teratology study 24
mated female Sprague-Dawley rats were dosed by gastric intubation with 0,
0.20, 0.75, 1.00, and 1.25 mg/kg/day of technical mevinphos in water on
gestation days 6 through 15. Based on data from this study, the Agency
determined that the fetotoxic, embryotoxic, and teratogenic r’IOELs were >1.00
mg/kg/day and concluded that mevinphos does not induce developmental effects
in rats.
Environmental Characteristics
Available data are insufficient to fully assess the environmental fate of
mevinphos and transport of mevinphos. Data gaps exist for nearly all
applicable studies. The available data indicate that mevinphos residues are
very mobile in sandy loam, silt loam, loam, and clay loam soils. Freundlich
Kads values ranged from 0.392 to 1.92 and Freundlich Kdes values ranged from
1.16 to 3.53. Data currently available are insufficient to characterize
mevinphos’s leaching potential for contamination of ground water. Data to
characterize the potential to contaminate groundwater are being required.
Treated areas should not be re-entered for at least 96-hours (4—days) for
citrus, grapes, nectarine and peach orchards; and 48—hours (2—days) for all
other mevinphos treated crops, unless protective clothing is worn.
Ecological Characteristics
Avian acute toxicity: Acute toxicity values of 1.34 mg/kg in the sharp-
tailed grouse and 4.63 mg/kg in the mallard duck.
Avian dietary toxicity: Subacute dietary toxicity values ranged from 236
ppm in the Japanese quail to 1991 ppm in the
mallard duck.
Freshwater fish acute toxicity: 96-hour acute toxicity values ranged fro i
11.9 ppb for rainbow trout to 22.5 ppb For
bluegill sunFish.
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Marine fish acute toxicity: LC 50 value of 640 ppb for sheepshead minnow.
Freshwater invertebrate toxicity: The acute toxicity values ranged from
0.18 ppb for Daphnia pulex to 5.00 ppb
for Pteronarcys cafifornica .
Marine invertebrate toxicity: 96-hour shell deposition EC 50 value of greater
than 1000 ppb for the Eastern oyster; EC 50
value of 150 ppb for brown shrimp.
These data show that technical mevinphos is very highly toxic to birds on an
acute oral basis; highly toxic to upland game birds and slightly toxic to
waterfowl on a dietary basis; very highly toxic to both warmwater and
coidwater fish species; very highly toxic to aquatic invertebrates; and
highly toxic to the brown shrimp and sheepshead minnow and moderately toxic
to the Eastern oyster.
TOLERANCE REASSESSMENT
Tolerances have been established for residues of mevinphos in a variety of
raw agricultural commodities (40 CFR 180.157). The Agency has evaluated the
residue and toxicology data supporting these tolerances and has determined
that a full tolerance reassessment for mevinphos cannot be made at this
time because of extensive residue chemistry and toxicology data gaps.
Because of these extensive data gaps, no significant new uses, including
group tolerances, will be granted until the Agency has received data
sufficient to thoroughly evaluate the çlietary exposure to rnevinphos.
In addition to United States tolerances, there are also Canadian tolerances,
Mexican tolerances, and Codex Maximum Residue Limits (MRL5) established for
mevinphos. However, some incompatibility exists between some of the
permanent Codex MRL5 and the U.S. tolerances. The issue of incompatibility
will be addressed when residue data are submitted and evaluated.
The Agency does not have sufficient data to support the established
tolerances for residues of nevinphos alpha and beta isomers in or on all
raw agricultural comodities (RACs).
Processing studies are required for apples, citrus fruits, grapes, plums,
potatoes, tomatoes, corn, and sorghum.
The initial Acceptable Daily Intake (ADI) for mevinphos was based on a 2-
year dog feeding study. On the basis of plasma and erythrocyte
cholinesterase inhibition, the No Observed Effect Level (NOEL) in this study
was defined as 0.025 mg/kg/day. A safety factor of 10 was used to calculate
the ADI of 0.0025 mg/kg/day. The cholinesterase inhibition Lowest Effect
Level (LEL) in this study was defined as 0.075 mg/kg/day. When the Agency
rereviewed this study in the reregistration review for mevinphos, serious
r-eport deficiencies were noted that made the study unaccepta5ie and
gency found that it was not possible to define the NOEL and LEL doses.
The , gency revi e’ ied sev ri chronic toxicity stu dies du ‘i ng the ievi n hos
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reregistration review process and all but one of them (a rat teratology
study) were found to be unacceptable. Therefore, the Agency concludes that
there is insufficient data to establish an AOl or PADI for mevinphos at this
time.
5. REQUIRED UNIQUE LABELING SUMMARY
The following revised environmental hazard statement must appear on the
label of all manufacturing—use products containing mevinphos: “This
pesticide is toxic to fish and wildlife. Do not discharge effluent
containing this product into lakes, streams, ponds, estuaries, oceans, or
public waters unless this product is specifically identified and addressed
in an NPDES permit. Do not discharge effluent containing this product to
sewer systems without previously notifying the sewage treatment plant
authority. For guidance, contact your State Water Board or Regional Office
of the Environmental Protection Agency.”
Personal protective equipnent and work safety statements for mixer/loaders
and applicators are required to be included on the label of all end-use
mevinphos products.
All end—use products containing nevinphos as an active ingredient, must bear
the following restricted use labeling statements:
“RESTRICTED USE PESTICIDE
Due to Very High Acute Toxicity to Humans
and
Residue Effects on Avian, Mammalian and
Aquatic Species
For retail sale to and use only by certified applicators or persons
under their direct supervision and only for those uses covered by the
certified applicator’s certification. Jirect supervision for this
product is defined as the certified applicator being physically present
during application, mixing, loading, repair and cleaning of application
equipment. Certified applicators must also ensure that all persons
involved in these activities are informed of the precautionary
statements.”
Environmental hazard statements and a bee precautionary statement must
appear on the label of all end—use mevinphos products.
The following reentry interval statement and protective clothing for early
reentry statement must appear on the labeling of all products except aquatic
non-food use products:
“Reentry into treated citrus groves, grape vineyards, nectarine and
peach orchards is prohibited for 96 hours (4 days) after the end of
application, unless the protective clothing specified on this libel for
early reentry is worn. Reentry into all other treated areas s
prohibited for 4R hours (2 dat’s) after the end of application, unless
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the protective clothing specified on this label for early reentry is
worn.
FOR EARLY REENTRY INTO TREATED AREAS AFTER SPRAYS HAVE DRIED: Use
protective suit of one or two pieces covering all parts of the body
except head, hands, and feet; chemical-resistant gloves; chemical-
resistant shoes (or chemical—resistant shoe covers or chemical-
resistant boots).
FOR EARLY REENTRY INTO TREATED AREAS BEFORE SPRAYS HAVE DRIED, wear all
protective clothing specified on this label for an applicator.
Written or oral warnings must be given to workers who are expected to
be in treated areas or in an area about to be treated with this
product. (Indicate specific oral warnings which inform workers of
areas or fields that may not be entered without specific protective
clothing, period of time field must be vacated and appropriate actions
to take in case of accidental exposure.) When oral warnings are given,
warnings shall be given in a language customarily understood by
workers. Oral warnings must be given if there is reason to believe
that written warnings cannot be understood by workers. Written
warnings must include the following information: DANGER: Area treated
with MEVINPHOS on (Date) ________________________________. Do not enter
without appropriate protective clothing until (insert date/time
reflecting end of reentry interval set forth on this label). In case
of accidental exposure see STATEMENTS OF PRACTICAL TREATMENT found on
the MEVINPHOS product label.”
The following statement must appear on the labeling of all products, except
aquatic non—food use products, which permit aerial application: “HUMAN
FLAGGERS ARE PROHIBITED during aerial application of this product unless in
totally enclosed vehicles.”
The telephone number of the National Pesticide Telecomunications letwork
must appear on the label of all end—use mevinphos product.
6. REGULATORY POSITION SUMMARY
The Agency will not grant any tolerances or any new uses for mevinphos until
sufficient data are submitted for the Agency to calculate the Theoretical
Maximum Residue Contribution (TMRC) for mevinphos and then will not grant
any tolerances or significant new food uses until all of the required
residue chemistry and toxicology data have been submitted and reviewed.
The Agency is continuing the restricted use classification of all mevinphos
products.
The Agency is establishing the following reentry intervals for end-use
mevinphos products: four days (96-hours) for citrus, groves,grape
vineyards, nectarine and peach orchards; and two days (48-hours) for all
other crops treated with nevinphos.
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The Agency is prohibiting the use of human flaggers during aerial
application of mevinphos unless the flaggers are in enclosed vehicles.
The agency is requiring the addition of the telephone number of the
National Pesticide Telecommunications Network to all end—use mevinphos
product labels.
The Office of Endangered Species (OES) in the U.S. Fish and Wildlife Service
(FWS) has determined that certain uses of mevinphos may jeopardize the
continued existence of endangered species or critical habitat of certain
endangered species. EPA is developing a program to reduce or eliminate
exposure to these species to a point where use does not result in jeopardy,
and will issue notice of any necessary labeling revisions when the program
is developed. No additional endangered species labeling is being required
at this time.
While data gaps are being filled, currently registered manufacturing use
products and end use products containing mevinphos may be sold, distributed,
formulated, and used, subject to the terms and conditions specified in the
Registration Standard for Mevinphos. Registrants must provide or agree to
develop additional data in order to maintain existing registrations.
7. Summary of Major Data Gaps
Toxicology
Acute Oral Toxicity
Acute Dermal Toxicity
Acute Inhalation Toxicity
Primary Eye Irritation
Primary Dermal Irritation
Derrnal Sensitization
Acute Delayed Neurotoxicity
Acute Dermal (to define lethality, toxicity, and ChE NOELs)
Subchronic 90-Day Feeding, two species (rodent and nonrodent) 1
Subchronic 90—Day Inhalation (to define toxicity from greenhouse
exposure)
Subchronic 21 Day Dernal
Subchronic Neurotoxicity (conditionally in hen and/or mammal)
Chronic Toxicity, two species (rodent and nonrodent)
Oncogenicity, two species
Teratogenicity (rabbit)
Reproducti on
Mutagenicity (full battery - Gene Mutation, Chromosonal Aberration and Other
Mechanism of Mutagenicity Studies)
Metabolism
1 lhis requirernent is waived since chronic studies are ranuired.
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Environmental Fate/Exposure
Hydrolysis
Photodegradati on, water
Photodegradation, soil
Photodegradation, air
Aerobic Soil Metabolism
Anaerobic Soil Metabolism
Anaerobic Aquatic Metabolism
Vol ati 1 i ty, laboratory
Volatility, field (pending results of the laboratory volatility study)
Terrestrial Field Dissipation
Aquatic Field Dissipation
Soil Dissipation, long term (reserved pending the results of the laboratory
fish accumulation study)
Confined Accumulation, rotational crops
Field Accumulation, rotational crops (deferred pending receipt of
acceptable confined rotational crop accunulation data)
Accumulation, irrigated crops
Fish Accumulation, laboratory
Field Accumulation, aquatic nontarget organisms (deferred pending the
receipt of acceptable accumulation in laboratory fish data)
Leaching and Adsorption/Desorption
Droplet Size Spectrum
Drift Field Evaluation
Ecological effects
Wild Marnal Toxicity
Avian Reproduction (upland game bird and waterfowl)
Freshwater Fish LC 50 (warmwater and coldwater species) (test material:
typical end-use product)
Freshwater Invertebrate LC 50 (test material: typical end-use product)
Estuarine and Marine Organisms LC 50 (fish and shrir’ip)
Fish Early Life Stage and Invertebrate Life Cycle
Aquatic Organism Accumulation
Honeybee - Toxicity of Residues on Foliage
Special Test - (Terrestrial Residue Monitoring of
(Avian and Mammalian Food Items)
Residue Chemistry
Nature of Residues (Plants, Livestock)
Storage Stability
Magnitude of Residues
Product Chemistry
All product chemistry studies
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8. CONTACT PERSON AT EPA
William H. 1iller
Product Manager (16)
Insecticide-Rodenticide Branch
Registration Division (TS—767C)
Office of Pesticide Programs
Environmental Protection Agency
401 M Street, S. W.
Washington, D. C. 20460
Office location and telephone number:
Room 211, Crystal Mall #2
1921 Jefferson Davis Highway
Arlington, VA 22202
(703) 557—2600
DISCLAIMER: The information presented in this Chemical Information Fact Sheet
is for informational purposes only and nay not be used to fulfill
data requirements for pesticide regi strati on and reregistration.
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