56-72-4

coumaphos is a tan crystalline solid with a slight sulfur odor. It is insoluble in water, slightly soluble in acetone, chloroform, and ethanol, and soluble in organic solvents. It is used for the control of a wide variety of livestock insects, including cattle grubs, screwworms, lice, scabies, fl ies, and ticks. It is used against ectoparasites, which are insects that live outside the host animals, such as sheep, goats, horses, pigs, and poultry. Coumaphos is incompatible with pyrethroids and piperonyl butoxide. The US EPA has grouped coumaphos as an RUP. Acute dermal exposures to occupational workers occur during mixing, loading, and application of coumaphos, especially in the livestock dip-vat and hand-held sprayer uses

Slightly brownish crystals with a slight sulfurous odor. Used for the control of a wide variety of livestock insects including cattle grubs, lice, scabies, flies, and ticks; the common ectoparasites of sheep, goats, horse, swine, and poultry as well as for screwworms in all these animals.

Organothiophosphates, such as COUMAPHOS(56-72-4), are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides. COUMAPHOS(56-72-4) reacts with strong oxidizing agents and alkaline materials.

Insoluble in water. This compound hydrolyzes slowly under alkaline conditions.

Use may be restricted; cholinesterase inhibitor. Questionable carcinogen.

Exposures to coumaphos cause signs of poisoning such as diarrhea, drooling, diffi culty in breathing, leg and neck stiffness among occupational workers. Acute inhalation of coumaphos causes headaches, dizziness, and incoordination. Moderate poisoning causes muscle twitching and vomiting while severe poisoning leads to fever, toxic psychosis, lung edema, and high blood pressure. Repeated exposures cause irritability, confusion, headache, speech diffi culties, effects on memory concentration, disorientation, severe depressions, sleepwalking, and drowsiness or insomnia among occupational workers. Coumaphos has been classifi ed as non-carcinogenic to humans

Very toxic, probable oral lethal dose is 50-500 mg/kg, or between 1 teaspoonful and 1 oz. for a 70 kg (150 lb.) person. May be fatal if inhaled, swallowed, or absorbed through skin. Contact may cause burns to skin and eyes.

A potential danger to those involved in the manufacture, formulation, and application of this material which is used for control of a wide variety of livestock insects including cattle grubs, lice scabies, flies, and ticks; the common ectoparasites of sheep, goats, horse, swine, and poultry; as well as for screw worms in all these animals.

When heated to decomposition, COUMAPHOS emits very toxic fumes of sulfur oxides, phosphorus oxides, and chlorides. Incompatible with piperonyl butoxide. Stable in water.

If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water, followed by alcohol. Speed in removing material from skin is of extreme importance. Shampoo hair promptly if contaminated. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a Medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit. Effects may be delayed. Keep victim under observation.

UN2783 Organo phosphorus pesticides, solid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous material. UN3018 Organophosphorus pesticides, liquid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.

Organophosphates are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrideds and active metals. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides. Keep away from piperonyl butoxide, oxidizers, strong bases, water, and heat

Coumaphos can be decomposed by heating with concentrated alkali. Large amounts should be incinerated in a unit equipped with effluent gas scrubbing. Do not discharge into drains or sewers. Dispose of waste material as hazardous waste using a licensed disposal contractor to an approved landfill. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (>=100 kg/mo) must conform to EPA regulations governing storage, transportation, treatment, and waste disposal. Incineration with effluent gas scrubbing is recommended. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. Must be disposed properly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office

Coumaphos is used to control larvae of Diptera and ticks on cattle. It has also recently been used to control Varroa mite in honeybees.

insecticide, cholinesterase inhibitor

Insecticide, nematocide.

ChEBI: Coumaphos is an organothiophosphate insecticide, an organic thiophosphate and an organochlorine compound. It has a role as an agrochemical, an acaricide, an antinematodal drug, an avicide and an EC 3.1.1.8 (cholinesterase) inhibitor. It is functionally related to a chlorferron.

Baymix (Bayer AnimalHealth); Meldane (Bayer Animal Health).

Insecticide, Nematocide; Veterinary medication: The U.S. EPA classifies the formulations 11.6% EC and 42% flowable concentrate end-use products as Restricted Use Pesticides (RUPs) because they pose a hazard of acute poisoning from ingestion. Coumaphos is an insecticide/acaricide used to control a wide variety of liver stock insects including cattle grubs, fleeceworms, lice scabies, flies, and ticks; the common ectoparasites of beef cattle, dairy cows, sheep, goats, horse, swine, and poultry as well as for screw worms in all these animals. The USDA uses coumaphos in dip vats along the U.S.-Texas border to control ticks that carry Texas Cattle Fever. It is added to cattle and poultry feed to control the development of fly larvae that breed in manure. It has applications in beekeeping.

AGRIDIP®; ASUNTOL®; AZUNTHOL®; BAY® 21/199; BAYER® 21/199; BAYMIX®; BAYMIX® 50; CHECKMITE®; CO-RAL®[C]; DELICE®; MELDANE®; MELDONE®; MUSCATOX®; NEGASHUNT®; DIOLICE®; RESITOX®; SUNTOL®; UMBETHION®

There was no evidence of carcinogenicity at any dose in rats fed diets that contained 1, 5, or 25 ppm coumaphos (0.05, 0.25, or 1.22 mg/kg/day (males); 0.07, 0.36, or 1.70 mg/kg/day (females)) for 2 years . There was no evidence of carcinogenicity in another study when rats were given diets that contained 10 or 20 ppm coumaphos for 103 weeks .

By UV irradiation of coumaphos in solutions, three dimeric products are isolated and identified as the head-to-tail anti-dimer, its oxidation product, and the head-to-tail syn-dimer.

Degradation occurs rapidly in the liver of the cow and rat. The principal metabolite excreted in urine is diethyl hydrogen phosphorothioate. Deethylation products are also found in lesser amounts. Photolytic DT₅₀ on soil surface is 23.8 d.

Color Code—Blue: Health Hazard/Poison: Storein a secure poison location. Store in tightly closed containers in a cool, well-ventilated area

Note that technical coumaphos may contain the dechlorinated analogue 'Potasan' (O-4-methyl-2-oxo-2H-chromen-7-yl O,O-diethyl phosphorothioate) (2) as an impurity (Waleski, 1966; Volpk and Mallet, 1976).
Coumaphos is stable to hydrolysis in aqueous media although the pyrone ring opens in dilute alkali and re-closes on acidification (PM). In water at pH 4.0, 5.5, 6.3, 7.0 and 8.5, the DT₅₀ values were 33, 67, 124, 347 and 29 days, respectively. Coumaphos degraded first to coroxon (coumaphos oxon) (3), presumably by an oxidative mechanism and this was hydrolysed to chlorferon (3-chloro-4-methyl-7-hydroxycoumarin)(4). The analysis was by TLC (Mallet and Volpe,1978).

The acute oral LD₅₀ values for male and female rats are 41 and 16 mg/kg, respectively. Inhalation LC50 values (1 h) for male and female rats are >1081 and 341 mg/m3 air. In 2-yr trials, rats tolerated 100 mg/kg diet.