Quality of sources of drinking water and health among the hill tribe people of northern Thailand.

Poor-quality drinking water can cause numerous health problems, particularly for people who are living with poor economic conditions, have a low educational status and have limited access to safe drinking water, such as the hill tribe people in Thailand. This study aimed to assess the quality of different sources of natural drinking water from the hill tribe villages in northern Thailand. Seventy-two drinking water samples from the hill tribe villages were collected and tested for biological, chemical and physical qualities, which were compared with the standard parameter values for safe drinking water according to the World Health Organization. Total coliform bacteria and fecal coliform bacteria, which represented the biological parameters, were detected in all samples. The physical parameters, which consisted of turbidity (36.1%), iron content (5.5%), color (2.7%) and pH (2.7%), exceeded the standard indications. However, the hazard quotient and hazard index values were less than 1. The hill tribe people are facing the problem of poor-quality drinking water, particularly in terms of biological and physical parameters that exceed the standard values. An effective program for improving access to safe water for the hill tribe people should be developed and implemented immediately.