EVALUATING HEALTH RISKS FROM OCCUPATIONAL EXPOSURE TO PESTICIDES AND THE REGULATORY RESPONSE

In this study, we used measurements of occupational exposures to pesti cides in agriculture to evaluate health risks and analyzed how the fed eral regulatory program is addressing these risks. Dose estimates deve loped by the State of California from measured occupational exposures to 41 pesticides were compared to standard indices of acute toxicity ( LD(50)) and chronic effects (reference dose). Lifetime cancer risks we re estimated using cancer potencies. Estimated absorbed daily doses fo r mixers, loaders, and applicators of pesticides ranged from less than 0.0001% to 48% of the estimated human LD(50) values, and doses for 10 of 40 pesticides exceeded 1% of the estimated human LD(50) values. Es timated lifetime absorbed daily doses ranged from 0.1% to 114,000% of the reference doses developed by the U.S. Environmental Protection Age ncy, and doses for 13 of 25 pesticides were above them. Lifetime cance r risks ranged from 1 per million to 1700 per million, and estimates f or 12 of 13 pesticides were above 1 per million. Similar results were obtained for field workers and flaggers. For the pesticides examined, exposures pose greater risks of chronic effects than acute effects. Ex posure reduction measures, including use of closed mixing systems and personal protective equipment, significantly reduced exposures. Propos ed regulations rely primarily on requirements for personal protective equipment and use restrictions to protect workers. Chronic health risk s are not considered in setting these requirements. Reviews of pestici des by the federal pesticide regulatory program have had little effect on occupational risks. Policy strategies that offer immediate protect ion for workers and that are not dependent on extensive review of indi vidual pesticides should be pursued.