Table 1: Definition of pattern of use and action required Action required Definition of pattern of use Baseline measurement should be carried out – Baseline two measurements are desirable, at a time when there has been at least four weeks without exposure. Use should be recorded. Very occasional use No test is needed unless the worker has If use of organophosphate symptoms which could be related to pesticides is only half a day organophosphate pesticides during or after use, every month or less, then this is or there has been an ‘exposure incident’ leading very occasional use. to symptoms. Use should be recorded. Intermittent use Test during the period of peak exposure/use. If use of organophosphate Testing provides valuable information on the pesticides is for two to three effectiveness of controls. days at a time, all day with gaps of time of a month or more Controls must be updated if levels of exposure between use, then this is indicate high work-related exposure. intermittent use. No further testing is needed unless the worker has symptoms which could be related to organophosphate pesticides during or after use, there has been an to ‘exposure incident’ leading symptoms, or there is concern ‘overexposure’ may have occurred. Use should be recorded. Seasonal use For heavy or seasonal use, testing should occur If use of organophosphate during the period of peak exposure/use. Workers pesticides is say four days a exposed should be tested at the end of the work week, and extends over a long shift on the last day of a work week, early in the season then, this is seasonal season, once work practices have settled, in use. order to check the effectiveness of work practices and controls. Adjustments to controls can be made if necessary. Workers must be advised of their results, that is percentage depression of cholinesterase from their baseline values. The timing of further tests should be based on the nature of the work and the previous test results. A worker having greater than 20% depression from baseline values should be retested at an early stage. No further test is needed unless the person has symptoms which could be related to organophosphate pesticides during or after use, there has been an leading ‘exposure incident’
Table 1: Definition of pattern of use and action required Definition of pattern of use Action required Baseline Baseline measurement should be carried out – two measurements are desirable, at a time when there has been at least four weeks without exposure. Very occasional use If use of organophosphate pesticides is only half a day every month or less, then this is very occasional use. Use should be recorded. No test is needed unless the worker has symptoms which could be related to organophosphate pesticides during or after use, or there has been an ‘exposure incident’ leading to symptoms. Intermittent use If use of organophosphate pesticides is for two to three days at a time, all day with gaps of time of a month or more between use, then this is intermittent use. Use should be recorded. Test during the period of peak exposure/use. Testing provides valuable information on the effectiveness of controls. Controls must be updated if levels of exposure indicate high work-related exposure. No further testing is needed unless the worker has symptoms which could be related to organophosphate pesticides during or after use, there has been an ‘exposure incident’ leading to symptoms, or there is concern ‘overexposure’ may have occurred. Seasonal use If use of organophosphate pesticides is say four days a week, and extends over a long season then, this is seasonal use. Use should be recorded. For heavy or seasonal use, testing should occur during the period of peak exposure/use. Workers exposed should be tested at the end of the work shift on the last day of a work week, early in the season, once work practices have settled, in order to check the effectiveness of work practices and controls. Adjustments to controls can be made if necessary. Workers must be advised of their results, that is percentage depression of cholinesterase from their baseline values. The timing of further tests should be based on the nature of the work and the previous test results. A worker having greater than 20% depression from baseline values should be retested at an early stage. No further test is needed unless the person has symptoms which could be related to organophosphate pesticides during or after use, there has been an ‘exposure incident’ leading
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