Relative inhibition of rat plasma and erythrocyte cholinesterases by pesticide combinations.

A selected combination of carbamate pesticides (carbofuran, oxamyl and propoxur were examined for cholinesterase (ChE) inhibition. The enzyme source was rat plasma and erythrocytes. Enzyme activity was determined colorimetrically using the Ellman technique adapted for erythrocyte ChE activity. Enzyme inhibition was obtained for both plasma and erythrocyte ChE, but inhibition by the pesticides was greater in the plasma. All 3 pesticides interacted additively in vitro.