Vietnamese farmers' health-risk awareness, knowledge, and practices related to their use of wastewater and human excreta was investigated in an anthropological study by a multidisciplinary team in peri-urban Hanoi and Nghe An Province. Farmers identified health risks associated with their use of excreta and wastewater, but they viewed these as unavoidable risks related to production. They perceived the health risks as different for the use of wastewater and human feces. They perceived health risks from wastewater as non-serious because it remained on the skin and only caused skin problems, but they considered health risks from non-composted smelly feces serious because it entered the body through 'polluted' air. Most farmers were more aware of threats to health from 'dirt' entering the domestic environment than of the health risks during their work. The concept of 'dirt' should be separated from understanding of germs, viruses, and parasites so that it is understood that things that carrying health risks cannot always be identified by their 'dirtiness' or smell. Farmers mainly considered hygiene and health as women's issues. Men's responsibility for the health and hygiene of the family should therefore be emphasized.