In gross aspects, the biochemical mechanisms in mice, cockroaches, 
and plants were similar. Major differences were concerned with rates 
of metabolism and degradation; and, as expected, rates were greater in 
the mammal than in the insect and greater in the insect than in plants. 
The routes of metabolism and the metabolites, however, were the same in 
each case. The principal metabolic path for both isomers was the oxi- 
dation of the 2-ethylthio ether to the sulfoxide and sulfone. In the 
case of demeton O, a secondary path involved oxidation of P=S to P=0 
with subsequent oxidation to the sulfoxide and sulfone (March et al., 
1955). 
Investigations with demeton-S have. shown that thin films undergo 
rapid conversion to more hydrophilic compounds when exposed to air and 
light. Following application to plants, demeton-S rapidly gave rise to 
at least three metabolites, two of which persisted for as long as 15 
weeks. Using chromatographic techniques, two of the compounds were 
identified as the corresponding sulfoxide and sulfone (Fukuto et al., 
1955; Heath et al., 1955; Thomas and Glynne-Jones, 1955; Thomas et al., 
1955; Thomas, 1956). 
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