Parathion

Favorites

Chemical Identification | General Product Information | Physical & Safety Data

Chemical Identification

Common Name

Parathion

中文通用名

对硫磷

IUPAC

O,O-diethyl O-4-nitrophenyl phosphorothioate

CAS

O,O-diethyl O-(4-nitrophenyl) phosphorothioate

CAS No.

56-38-2

Molecular Formula

C₁₀H₁₄NO₅PS

Molecular Structure

General Product Information

Category

Insecticides > Organophosphorus insecticides
Acaricides / Miticides > Organophosphorus acaricides

Activity

Insecticide, acaricide

Premix

Parathion-methyl+trichlorfon
Parathion-methyl+phoxim
Parathion+trichlorfon
Methamidophos+parathion-methyl
Endosulfan+parathion-methyl
Cyhalothrin+parathion-methyl+isocarbophos
Dusts, emulsion concentrates, granules, ULV liquid, wettable powders.
Premix Parters: primisulfuron-methyl;

Physical & Safety Data

Physical Properties

Pale yellow liquid. Melting point 6.1°C. Hydrolyzes slowly at pH 7 or below. Specific gravity 1.26. Incompatible with alkaline materials. Readily soluble in dichloromethane, 2-propanol, toluene. Soluble in n-hexane.Molecular weight:291.3; Physical form:Pale yellow liquid, with a phenol-like odour. Density:1.2694; Composition:Tech. grade is 96-98%. Melting point:6.1 °C; Flash point:174 °C ( tech.); Vapour pressure:0.89 mPa (20 °C); Henry constant:0.0302 Pa m3 mol-1; Partition coefficient(n-octanol and water):logP = 3.83; Solubility:In water 11 mg/l (20 °C). Completely miscible with most organic solvents, e.g. dichloromethane >200, isopropanol, toluene, hexane 50-100 (all in g/l, 20 °C).; Stability:Hydrolysed very slowly in acidic media ( pH 1-6), more rapidly in alkaline media; DT50 (22 °C) 272 d ( pH 4), 260 d ( pH 7), 130 d ( pH 9). Isomerises on heating ab.

Toxicology

Oral:Acute oral LD₅₀ for rats c. 2, mice c. 12, guinea pigs c. 10 mg/ kg. Percutaneous:Acute percutaneous LD₅₀ for male rats 71, female rats 76 mg/kg. Not irritating to skin and eyes (rabbits). Not a skin sensitiser. Inhalation: LC₅₀ (4 h) for male and female rats 0.03 mg/l (aerosol). Phytotoxicity:Non-phytotoxic, except to some ornamentals, cucurbits, sorghum, and some varieties of apple, pear, and tomato.

Environmental Profile

Ecotoxicology:
Algae: E_rC₅₀ for Scenedesmus subspicatus 0.5 mg/l.Bees:Toxic to bees.Daphnia: LC₅₀ (48 h) 0.0025 mg/l.Fish: LC₅₀ (96 h) for rainbow trout 1.5, golden orfe 0.58 mg/l.Worms: LC₅₀ for Eisenia foetida 267 mg/ kg dry soil.

Environmental fate:
Animals:In rats, following oral administration, 4-nitrophenol and paraoxon were the principal metabolites excreted (M. P. Carver, Pestic. Biochem. Physiol., 1990, 38, 254; L. G. Sultatos & C. L. Gagliardi, Biochem. Pharmacol., 1Soil:Based on K_oc values and leaching studies, parathion can be classified as a compound with low mobility. In biologically-active soils, parathion is rapidly degraded under laboratory conditions as well as in the field. The degradaPlant:The major metabolites are paraoxon, diethylphosphate, 4-nitrophenol and photometabolites S-ethyl parathion and S-phenyl parathion. WATER SOLUBILITY: 12.4 mg/l at 25°C

Transport Information

Signal Word:DANGER; Hazard Class:Ib(Highly hazardous)