Deaths on shrimp farm from suspected hydrogen sulfide poisoning in the confined well: Experienced people also being at risk

Abstract

Introduction: On 6 September 2020, the joint investigation team of the Department of Disease Control, Thailand, was notified about the death of three informal workers in a water well on a shrimp farm in Prachuap Khiri Khan Province. Objective: The objectives were to verify the diagnosis of the event, to describe epidemiological characteristics of the cases, to identify risk factors of the event, and to assess knowledge, attitude and practice (KAP) on the risk of working in water wells among the villagers. Methodology: We conducted a cross-sectional questionnaire survey to identify the event's risk factors and assess KAP of the villagers concerning the experiences of working in water wells. Chi-square test was performed. Results: The index case's most likely cause of death was hydrogen sulfide (H2S) poisoning, followed by drowning. The main fatality risk was a lack of knowledge and insufficient awareness of the danger of working in water wells, especially among those with prior experience of working in water wells. Conclusion: Occupational safety regulations and guidelines need to be developed and enforced to protect workers operating in the wells. Mitigation strategies included the avoidance of work in confined spaces as much as possible, and using proper engineering techniques for rescuing the victims if needed.