Sewage workers: toxic hazards and health effects.

Municipal sewage workers provide an essential service in the protection of public health. The wastewater treatment process brings the worker in contact with multiple pathogens, toxic gases, chemicals, and physical hazards. Issues such as the prevalence of hepatitis A among wastewater treatment workers in the U.S. have not been well studied. There remains a controversy on the need to offer hepatitis A pre-exposure immunization. Health effects to some exposures, such as gram-negative bacteria and endotoxins, have been well studied among other workers, and preventive measures, such as permissible endotoxin levels, that have been established for these workers should be adopted for the wastewater treatment environment. Further study into mortality and morbidity rates among sewage workers and the relationship to exposures and the development of preventive measures is needed.