Investigation of a group occupational acute dimethylacetamide poisoning incident
Objective To investigate and analyze a group occupational acute dimethylacetamide(DMA)poisoning incident occurred during the post-fire cleaning operation in a spandex manufacturing enterprise.Methods This study focused on the involved enterprise,employing units,poisoning patients,and workers with similar occupational exposure history from a group occupational acute chemical poisoning incident in Guangdong Province in 2023.Occupational health on-site investigation data,clinical records of poisoned patients,and occupational disease diagnostic data were collected to determine the cause of the poisoning.Results The incident occurred at a spandex manufacturing enterprise during the cleaning of polymerization reaction vessels after a fire,resulting in poisoning of six cleaning workers.The clinical symptoms of patients included varying degrees of liver function abnormalities and skin damage.All six patients wore long-tube air-supplied full-face masks during work.The patients were in a confined work space with poor ventilation,and worked more than 8 hours per day.Patients felt unwell after 5-13 days of work.Post-incident investigation revealed that the DMA exposure concentration of short term near the reaction vessels was 36.06 mg/m³.DMA accounted 13.74%to 30.09%of the volatile organic compounds in the raw and auxiliary materials and waste in the vessel.N-methylacetamide was detected in the urine of these six patients,with levels up to 1 639.78 mg/g creatinine,exceeding the occupational exposure limit(20.00 mg/g creatinine).All six patients were diagnosed as occupational acute DMA poisoning.Conclusion Occupational acute DMA poisoning mainly causes liver damage,has a latent onset,and poses a risk of group occurrence.The main causes of group poisoning are confined work space,inadequate management,insufficient protective measures,and excessive working hours.
DimethylacetamideAcute poisoningOccupational poisoningChemical poisoningInvestigation and analysis