Organophosphorous pesticides are anticholinergic and health surveillance is recommended for workers using these pesticides on a regular basis. HSE's previous guidance (MS17) gives more information on this, including measuring plasma and red blood cell cholinesterase activity.
Cholinesterase activity varies widely between individuals. It is therefore recommended that workers under health surveillance have a baseline measurement (undertaken before working with organophosphorous pesticides or six weeks after the end of exposure) as well as being sampled during exposure tasks.
Minimal variability of the test is important in order to be able detect small effects before any symptoms of exposure are apparent. We have conducted a lot of research in this area and the analytical variation of our methods is excellent (<4%) allowing us to detect a drop in activity of <15%. This allows intervention in working practice before activity drops to 30% (the point at which HSE recommend medical examination).
Our method is long-standing and we participate in the UKNEQAS quality assurance scheme for plasma cholinesterase. We report both plasma butyrylcholinesterase (also called pseudocholinesterase, a sensitive marker of exposure) and erythrocyte (or red cell) acetylcholinesterase (more directly associated with health effects).
Technical or order enquiries
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