[Degradation of soil quality: health and environmental risks]

This is a general survey of soil quality degradation and its consequences on human health and environment quality. The first part deals with the large complexity and reactivity of soil and its specific position as an environmental interface. The origin and behaviour of the main pollutant accumulated in soils are treated in the second and third parts. A special attention is paid to the main pollutants i.e., anions, cations (trace elements), pesticides, persistent organic pollutants (POP), bacteria, DNA... As they are closely linked to the soil constituents (clays, humus...), their real toxicity or effectiveness is examined. In the last part, the risks of soil pollutants for the environment and human health are shortly considered. Direct risks for health are few and mainly concern the ingestion of polluted soil by children; as regards the ecotoxicological and toxicological risks, the Critical pollutant loads have to be defined. The main risks are indirect and involve pollution of either the food chain or of the water and sediments by vertical or lateral (erosion) transfers.