Understanding and measuring the consequences of environmental pollution
on human health remains a challenge. Several barriers arise, with the diffi culty
in identifying uncommon pathologies but also with the limited knowledge of the
real health status of populations that depends on the supply and use of care. In an
effort to assess these barriers, we chose a study area severely affected by agricultural
intensifi cation to investigate the potential and visible impact of water pollution
on human health. Located in northern Thailand, the study area includes a watershed,
its reservoir and the irrigated area downstream. A questionnaire-based survey was
conducted to assess the exposure of 297 households to potential water pollutions
and understand their behaviour regarding the use of water and recourse to health
services. The observations are discussed in the light of the epidemiological records
provided by the Ministry of Public Health for the same area. The study shows the
heterogeneity of the epidemiological data and the diffi culty to assess the sanitary
risk. Despite the small size of the study area, inequalities are observed, with remote
populations having a poorer access to water with occasional shortage and a limited
use of health services. In this context, the intensifi cation of agriculture and the
massive use of pesticides and fertilizers are likely to have serious consequences on
human health. However, the impact of potential environmental pollution is not
visible from the epidemiological records, because of a diffi cult diagnosis, a lack of
consultation when symptoms are reversible and the long latency before clinical
symptoms are apparent (example of cancers). Prevention and incentive from health
authorities should help in reducing this risk.