Oxamyl toxicity

Kennedy, G.D., Jr. Acute toxicity studies with oxamyl, Fundam. Appl. Toxicol., 6(3) 423-429, 1986. 

The most important inhibitors of CarbEs are organo-phosphorus insecticides (malathion, parathion, para-oxon, methyl parathion, EPN, and others), nerve agents (DFP, soman, sarin, tabun, and VX) and carbamate insecticides (carbofuran, carbaryl, aldicarb, propoxur, oxamyl, methomyl, and others). Organo-phosphorus toxicants inhibit CarbEs irreversibly by phosphorylation and carbamates inhibit CarbEs reversibly by carbamylation similar to the basic mechanism (i.e., acylation of the active site) ... 

We shall describe some properties of carbaryl and carbofuran, aldicarb and oxamyl, and pirimicarb and ethiofencarb because their properties are contrasting. Table 5.4 shows that their toxicities vary widely. 

Oxamyl has a high acute toxicity displaying the typical effects of carbamate insecticides, e.g. rapid onset of cholinesterase inhibition followed by rapid recovery. Symptoms of acute intoxication in animals included tremors, salivation, lacrimation, bulging eyes, and muscular twitching. The oral LD50 for oxamyl in the rat is the range of 5 to 15 mg/kg. 

Gupta, R. C. (1994b). Mechanistic and clinical apprftaches in antidotal treatment with memantine and atropine aguiasl oxamyl and mcthomyl-acute toxicity, hul. J. To.xicoL 1, I-10. 

Chemical/Physical. The hydrolysis half-lives of oxamyl in a sterile 1% ethanol/water solution at 25°C and pH values of 4.5, 6.0, 7.0 and 8.0, were 300, 17, 1.6 and 0.20 weeks, respectively (Chapman and Cole, 1982). Under alkaline conditions, oxamyl hydrolyzed following first-order kinetics (Bromilow et al., 1980). Emits toxic finnes of nitrogen and sulfur oxides when heated to decomposition (Sax and Lewis, 1987). 

Carbamates include aldicarb, methiocarb, methomyl, carbofuran, ben-diocarb and oxamyl. Although they are broad-spectrum insecticides, with moderate toxicity and persistence, they rarely bioaccumulate or cause major environmental impacts [25],... 

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