Workers Poisoned by Pesticide
(Beyond Pesticides, August 21, 2003) Workers at a recycling plant in Edmonton, Canada were exposed to a pesticide last week, after someone carelessly discarded a partially used container of mosquito-killer into a recycling bin. The container, which held the organophosphate insecticide malathion, was crushed and unloaded into the plant last Monday, August 11. Staff, some of whom were hospitalized and later released, suffered headaches and vomiting that day and the following Tuesday and Wednesday. The plant closed its doors on Thursday when a stop-work order was issued by Alberta Workplace Health and Safety. According to Chris Chodan, a spokesman for Alberta Human Resources and Employment, the plant will not reopen until an investigation is completed and workers are given instructions on how to avoid future exposures.
The facility's staff tried to decontaminate the plant, their first attempt involving the removal of materials they believed were contaminated. However, the poison remained, and the staff was forced to empty everything from the building - 400 tons of recyclables - to be sent to a landfill.
Officials advised residents that any containers holding toxic goods, such as pesticides, should be taken to the city's eco stations.
Malathion is a nerve poison, which acts by inhibiting the enzyme acetylcholine esterase(AchE), and probably acts at other sites in the nervous system as well. Cases of long-lasting neuropathy and sensory damage have been reported in humans, as well as behavioral changes, after malathion exposure. Corresponding indications of neurotoxicity are seen in animal studies. Acute effects of malathion exposure include nausea, dizziness and confusion.
Despite the health risk that malathion poses to humans, many towns in the U.S. are opting to spray this organophosphate on residential streets as part of a mosquito control program. Historically, community-wide spraying of malathion has been shown to be dangerous. A November 1999 report issued by the Center for Disease Control (CDC) recommended that Florida find alternatives to malathion to fight the Mediterranean fruit fly. According to the CDC report, over 230 people had reported being sick after malathion was sprayed aerially during the previous Medfly Eradication Program.
To find out more about the toxicity of malathion, see Beyond Pesticides' Malathion ChemWATCH Fact Sheet. For information and resources on how to promote safer mosquito management in your community, see Beyond Pesticides' West Nile Virus and Mosquito Management Program Page.