10-Monohydro mirex

Radiolabeling experiments showed that mirex is not metabolized in humans, rodents, cows, or minipigs the parent compound was the only radiolabeled compound present in the plasma, fat, and feces (Dorough and Ivie 1974 Gibson et al. 1972 Kutz et al. 1974 Mehendale et al. 1972 Morgan et al. 1979). Flowever, a monohydro derivative of mirex was identified in the feces, but not the fat or plasma, of rhesus monkeys given an oral or intravenous dose of mirex (Pittman et al. 1976 Stein et al. 1976 Wener et al. 1976). It is believed that the suspected metabolite may have arisen as a result of bacterial action in the lower gut or in the feces (Stein et al. 1976). 

Following oral administration of 1 mg/kg 14C mirex to a female rhesus monkey, 25% of the 14C was recovered in the feces within 48 hours, with a cumulative excretion of 26.5% over 23 days. Less than 1% was recovered in the urine over 23 days (Wiener et al. 1976). A monohydro derivative of mirex was identified in the feces of rhesus monkeys given daily doses of 1 mg/kg mirex (Stein and Pittman 1977). The exact duration of dosing was not specified (Stein and Pittman 1977). 

Mirex is a very persistent compound in the environment and is highly resistant to both chemical and biological degradation. The primary process for the degradation of mirex is photolysis in water or on soil surfaces photomirex is the major transformation product of photolysis. In soil or sediments, anaerobic biodegradation is also a major removal mechanism whereby mirex is slowly dechlorinated to the 10-monohydro derivative. Aerobic biodegradation on soil is a very slow and minor degradation process. Twelve years after the application of mirex to soil, 50% of the mirex and mirex-related compounds remained on the soil. Between 65--73% of the residues recovered were mirex and 3-6% were chlordecone, a transformation product (Carlson et al. 1976). 

Under anaerobic conditions, mirex was slowly dechlorinated to the 10-monohydro derivative by incubation with sewage sludge bacteria for two months (Andrade and Wheeler 1974 Andrade et al. 1975 Williams 1977). The primary removal mechanism for mirex was anaerobic degradation as demonstrated by the 6-month stability of the compound in nine aerobic soils and lake sediments (Jones and Hodges 1974). 

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