Description:
N,N-Diethyl-m-toluamide, commonly known as DEET, is broadly used as an active ingredient in insect repellents ([http://www.ncbi.nlm.nih.gov/pubmed/17337538|Rivera-Cancel et al., 2007]). In the United States, 30% of people use an insect repellent containing DEET at least once a year ([http://www.ncbi.nlm.nih.gov/pubmed/11693870|McGready et al., 2001]). Annual domestic use equals approximately 1,800 tons ([http://www.ncbi.nlm.nih.gov/pubmed/17337538|Rivera-Cancel et al., 2007]). DEET was originally patented by the United States Army for use in insect-infested areas and was later registered for use by the general public. DEET is not known to have carcinogenic effects on humans (EXTOXNET; Pesticide Information Profile: DEET). While not carcinogenic, exposure to N,N-diethyl-m-toluamide does have human health effects including skin reactions and in rare cases of high-level exposure, seizures, toxic encephalopathy, acute manic psychosis and death (TOXNET; Hazardous Substances Data Bank; DEET). Hydrolysis of the amide bond in N,N-Diethyl-m-toluamide yields 3-methylbenzoate and diethylamine. This transformation is catalyzed by the enzyme DEET hydrolase under aerobic conditions by the bacterium P. putida DTB. The resulting 3-methylbenzoate is then converted to 3-methylcatechol which can be further metabolized through the meta cleavage pathway of Pseudomonas putida ([http://www.ncbi.nlm.nih.gov/pubmed/17337538|Rivera-Cancel et al., 2007]). Diethylamine and ethylamine are both hydrolyzed to acetaldehyde before entering central metabolism ([http://www.ncbi.nlm.nih.gov/pubmed/1268229|Steenkamp et al., 1976]). In laboratory batch experiments with activated sludge from a membrane bioreactor, the two main products observed were the product of enzymatic dealkylation and the product of enzymatic oxidation.