Soil and Fresh Water

In nature, soil and water systems are intimately inter-related through a complex web of interactions. In this chapter, the nature and properties of soils are reviewed with emphasis on chemical composition and the binding, cycling and transformation of chemical substances in soil. The main focus is on metals, but organic compounds are also discussed. Water is discussed mainly as an exposure route from soil to humans. Various aspects of pollution of soil and water systems are discussed, including industry and mining, long-range atmospheric transport, pesticides and fertilizers and waste disposal sites. The possible health effects of soil and water acidification are treated, with emphasis on cadmium, lead, mercury and aluminium. Finally, some health aspects of drinking water are discussed, with emphasis on instances where toxic substances at least partly have their origin in soils, and where drinking water constitutes an important exposure pathway from soils to humans. This includes arsenic, with a focus on West Bengal, fluoride, water hardness, nitrate and chlorination by-products. Keywords: soil; drinking water; acidification; cadmium; lead; mercury; aluminium; arsenic; chlorination by-products