CARBARYL

Common name: Carbaryl

Chemical name: 1-Napthyl methylcarbamate

Structural formula:

Chemical class: Carbamate insecticide

CAS NO.: 63-25-2

Properties: Technical product is white crystalline powder. M.p. 142 ℃ . V.p. 4.1 × 10 -2 mPa (23.5 ℃ ). Soluble in water 120mg/L (20 ℃ ). Readily soluble in polar organic solvents. In dimethylformamide, dimethyl sulfoxide 400-450, acetone 200-300, cyclohexanone 200-250, isopropanol 100, xylene 100 (all in g/kg at 25 ℃ ). Stable under neutral and weakly acidic conditions. Hydrolysed in alkaline media to 1-naphthol; DT 50 c. 12 d (pH 7), 3.2 h (pH 9). Stable to light and heat.

Toxicity: Acute oral LD 50 for male rats 850, female rats 500, rabbits 710 mg/kg. Acute percutaneous LD 50 for rats ﹥ 4000, rabbits ﹥ 2000mg/kg. Non-irritating to skin and eyes (rabbits). Inhalational LC 50 for rats ﹥ 206.1 mg/L air.

Ecotoxicology: Birds, acute oral LD 50 for young mallard ducks ﹥ 2179, young pheasants ﹥ 2000, pigeons 1000-3000 mg/kg. Fish, LC 50 (96 h) for rainbow trout 1.3, sheepshead minnow 2.2, bluegill sunfish 10 mg/L. Bees, toxic to bees; LD 50 (topical) 1 μ g/bee. Daphnia, LC 50 (48 h) 0.006 mg/L.

Environmental fate: Animals, in mammals, carbaryl does not accumulate in body tissues, but is rapidly metabolized to non-toxic substances, particularly 1-naphthol. This, together with the glucuronic acid conjugate, is eliminated predominantly in the urine and faeces. Metabolism of carbamate insecticides in reviewed. Plants, metabolites are 4-hydroxycarbaryl, 5-hydroxycarbaryl and methylol-carbaryl. Soil/Environment, under aerobic conditions, carbaryl at 1 ppm degraded with DT 50 7-14 d in a sandy loam and 14-28 d in a clay loam.

Treatment: Antidote: Atropine. Do NOT use 2-PAM, opiates, or cholinesterase inhibiting drugs.

      Symptomatic treatment.

Mode of action: Insecticide with contact and stomach action, and slight systemic properties.

Usage: Control of Lepidoptera, Coleoptera, and other chewing and sucking insects on more than 120 different crops. Control of earthworms in turf. Used as a growth regulator for fruit thinning of apples. Also used as an animal ectoparasiticide.