Repeatability and validity of a field kit for estimation of cholinesterase in whole blood.
Objectives-To evaluate a spectrophotometric field kit (Test-Mate-OP) for repeatability and validity in comparison with reference laboratory methods and to model its anticipated sensitivity and specificity based on these findings.
Methods-76 farm workers between the age of 20 and 55, of whom 30 were pesticide applicators exposed to a range of organophosphates in the preceding 10 days, had blood taken for plasma cholinesterase (PCE) and erythrocyte cholinesterase (ECE) measurement by field kit or laboratory methods.
Paired blinded duplicate samples were taken from subgroups in the sample to assess repeatability of laboratory and field kit methods.
Field kits were also used to test venous blood in one subgroup.
The variance obtained for the field kit tests was then applied to two hypothetical scenarios that used published action guidelines to model the kit's sensitivity and specificity.
Repeatability for PCE was much poorer and for ECE slightly poorer than that of laboratory measures.
A substantial upward bias for field kit ECE relative to laboratory measurements was found.
Sensitivity of the kit to a 40% drop in PCE was 67%, whereas that for ECE was 89%. Specificity of the kit with no change in mean of the population was 100% for ECE and 91% for PCE.
Mots-clés Pascal : Pesticide, Organophosphoré, Anticholinestérasique, Homme, Méthode étude, Activité enzymatique, Cholinesterase, Carboxylic ester hydrolases, Esterases, Hydrolases, Enzyme, Surveillance biologique, Sang, Evaluation performance, Exposition professionnelle, Agriculture, Médecine travail
Mots-clés Pascal anglais : Pesticides, Organophosphorus compounds, Anticholinesterase agent, Human, Investigation method, Enzymatic activity, Cholinesterase, Carboxylic ester hydrolases, Esterases, Hydrolases, Enzyme, Biological monitoring, Blood, Performance evaluation, Occupational exposure, Agriculture, Occupational medicine
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 95-0118523
Code Inist : 002B03G. Création : 09/06/1995.