Health risk analysis of the Rio de Janeiro water supply using geographical information systems

Assessment of health risk in population groups is based on environmental, socio-economic, and health data. A Geographic Information System (GIS) was used to simultaneously analyse databases with different origins. The case of health risk related to vulnerability of water supply in the city of Rio de Janeiro was examined using information on the water supply system with epidemiological, and socio-economic indicators. The water-distribution system covers nearly all the city territory, and the main treatment plant produces water that meets water quality guidelines. However, important factors remain harmful to public health due to the presence of contamination sources throughout the distribution system and vulnerable small springs. Problems detected involve characteristic city areas constituting one third of the total city population.