Occupational Paraquat Exposure Cases Reported to the Ramathibodi Poison Center
Abstract
Objective Paraquat (PQ) is a widely used non-specific herbicide. Para-quat poisoning both from intentional and unintentional exposure has been reported. The main objective of this study is to report on the characteristics, clinical effects, and outcomes of occupational PQ exposure reported to a poison control center in Thailand. The secondary objective is to determine factors associated with systemic toxicity from occupational PQ exposure.
Methods This is a retrospective study of cases of occupational PQ exposure reported to the Ramathibodi Poison Center between January 2018 and December 2021.
Results There were 124 PQ exposure cases during the study period, including 102 males and 22 females. Median age was 46 years (interquartile range 35.5-55.5 years). Routes of exposure included dermal (54.8%), inhalational (37.1%), and ocular (13.7%). Commonly used personal protective equipment (PPE) included trousers (18.5%), long-sleeve shirts (16.9%), and balaclavas (10.4%). Of the 68 dermal exposures, 23 (33.8%) reported having attempted skin decontamination prior to visiting the hospital. Systemic effects were reported in 22 cases (17.7%), including kidney injury (17.7%), hepatic injury (4.8%), and pulmonary injury (8.1%). All cases with systemic effects involved dermal exposures. Factors associated with systemic effects include mixing process, dermal exposure, lack of early skin decontamination, longer period between exposure and hospital visit, presence of wounds, body surface area involved and the grade of wounds.
Conclusions Occupational dermal PQ exposure can result in systemic effects. Individuals who handle PQ should be trained in and encouraged to practice safe PQ use, e.g., wearing personal protective equipment and using appropriate first aid measures if PQ exposure occurs.
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