|Chemical Abstract Number (CAS #)||
|Synonyms||Coumaphos||Coumarin, 3-chloro-7-hydroxy-4-methyl-, O-ester with
O,O-diethylpyrophosphorothioate||Co-Ral||Phosphorothioic acid, O-(3-chloro-4-methyl-2-oxo-2H-1-benzopyran-7-yl) O,O-diethyl
||EPA Method 8141|
Link to the National Library of Medicine's Hazardous Substances
Database for more details
on this compound.
|Use|| Medication (Vet): Anthelmintic
MEDICATION (VET): Treatment of screwworms, maggots, ear ticks on livestock
FEED ADDITIVE FOR CATTLE & POULTRY, TO CONTROL LARVAE OF FECAL
BREEDING FLIES; AS DUST, DIP, OR SPRAY FOR CONTROL OF MANGE, HORN
FLIES, & FACE FLIES OF CATTLE; HAS ALSO BEEN INCORPORATED IN WOUND
INSECTICIDE FOR CATTLE GRUBS, LICE, ECTOPARASITES OF SHEEP, GOATS,
HORSES, SWINE, POULTRY.
|Consumption Patterns|| 100%, OR 1.8X10 8 G AS A LIVESTOCK INSECTICIDE (FOR CATTLE GRUBS,
TICKS, FLIES, LICE, ECTOPARASITES ON SHEEP, GOATS, HORSES, SWINE,
POULTRY, & LIVESTOCK SCREWWORMS) (1974 EST)
|Apparent Color|| Tan crystalline solid
|Odor|| Slight sulfur-like odor
|Melting Point|| 91 DEG C
|Molecular Weight|| 362.78
|Density|| 1.47 @ 20 deg C/4 deg C
|Odor Threshold Concentration|| 2.0X10-2 ppm (Detection in water; purity not specified).
|Sensitivity Data|| Irritating to skin and eyes
|Environmental Impact|| Coumaphos is a veterinary insecticide used to control ectoparasites on livestock and
poultry, fly larvae in poultry fecal material, and gastrointestinal nematodes. It may be released to
the environment in wastewater, spills, and as aerosols during its production, formulation, and use
in spraying or dipping livestock and poultry including disposal of dipping solutions, and cleaning
vats and spray equipment. If spilled on land, coumaphos would be expected to adsorb strongly to
the soil and very slowly biodegrade (half-life 200 - 300 days). If released as wastewater,
coumaphos should adsorb strongly to sediment and particulate matter in the water column. It has
been reported to disappear from pond water (pH 5.5) in less than 7 days although the processes
contributing to this disappearance are not clear. There is a moderate potential for
bioconcentration in aquatic organisms. In the atmosphere, coumaphos would most likely be in the
form of an aerosol. It will be subject to gravitational settling and may photolyze. Exposure will be
primarily occupational by dermal contact.
|Environmental Fate|| TERRESTRIAL FATE: If spilled on land, coumaphos would be expected to adsorb
strongly to the soil. Biodegradation would be extremely slow (half-life 200-300 days).
AQUATIC FATE: If released into water, coumaphos should adsorb strongly to sediment and
particulate matter in the water column. While chemical hydrolysis and biodegradation are
reportedly slow, the only available study in environmental waters found that coumaphos
disappeared from pond water (pH 5.5) in less than 7 days. Volatilization would not be a
significant loss process.
ATMOSPHERIC FATE: If released into air, coumaphos would most likely be in the form of an
aerosol and be subject to gravitational settling. Photolysis may occur; however, no
environmentally relevant rates are available for this process.
|Drinking Water Impact|| Coumaphos was not detected in 82 water samples collected from 1964-1966 in New
York State at a detection limit of 10 ppb .