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CAS Number: 333-41-5
Synonyms: Basudin, Dazzel, Gardentox, Kayazol, Knox Out, Nucidol, Spectracide
Contaminant Type: Chemical

Diazinon is an organophosphorus insecticide  classified by the World Health Organization (WHO) as "moderately hazardous" Class II.  It is relatively water soluble, non-polar, moderately mobile and persistent in soil [763]. It's IUPAC name is O,O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl phosphorothioate.

Over 13 million lbs of diazinon are applied annually in the United States. Diazinon and its metabolites have been detected in aquatic systems worldwide [763].  Additionally, high diazinon residues were found in urbane water-ways and effluents from sewage treatments plants [764].  Diazinon is manufactured in the United States and formulated as granules, a wettable powder, an emulsifiable solution, a dust, a seed dressing, or a mixed formulation with other insecticides[762].

Diazinon in drinking water is not regulated by the USEPA.

Fatal human doses were found to be in the range of 90 to 444 mg/kg.  Toxic effects of diazinon are attributed to its inhibition of the enzyme acetylcholinestrase [763].

Date of Literature Search: June 2009

762 USDHHS; 2008; Toxicological profile for diazinon; Toxicological profile for diazinon; pp. 133-135. Agency for Toxic Substances and Disease Registry, Division of Toxicology and Environmental Medicine/Applied Toxicology Branch, U.S. Department of Health and Human Services, Atlanta, GA.
763 Shemer, H. and Linen, K.; 2006; Degradation and by-products formation of diazinon in water during UV and UV/H2O2 treament; J. Hazardous Materials; B136:3:553
764 Basfar, A., Mohamed, A., Al-Abduly, A., Al-Kuraiji, A. and Al-Shahrani, A.; 2007; Degradation of diazinon contaminated waters by ionizing radiation.; Radiat. Phys. Chem.; 76:8-9:1474