The estimation of serum cholinesterasr in the presence of anti-cholinesterase insecticides

Abstract

Six methods have been employed for the assay of serum cholinesterase in the presence of a number of anti-cholinesterase insecticides, of which three were carbamates and two organophosphorus compounds. Inhibition of cholinesterase activity was demonstrated in every case, but four of the methods underestimated the degree of inhibition. It was found that if serum samples to which four of the five insecticides had been added were left at room temperature for 24 hours there was almost complete recovery of the cholinesterase activity. This did not occur if the samples were stored at −15°. On the basis of these studies two methods are recommended for the estimation of serum cholinesterase in the presence of anti-cholinesterase insecticides.