Soil health and human well-being: a review

A range of positive and negative impacts of soil on human health are reviewed in this article. Soil has a variety of positive functions that support human health. It supplies nutrients to the plants and eventually to the human body via food intake. Soil helps purification of water and serves as foundation for buildings. Healthy soils impact carbon sequestration, greenhouse gas reduction, adequate nutrient supply, water retention and efficient biodiversity. Both soil macroorganisms (e.g. earthworms) and microorganisms (e.g. N2 fixing bacteria) perform great role on soil health, and soil health in turn has good linkage with human health. Nevertheless, soils can exert negative impact on human health. Negative health effects occur when foods are grown in soils that have nutrient deficiencies or toxicities and when toxic heavy metals (e.g. Cd, As, Pb, Hg) are transferred from soils into the plants and then into the human food chain. People are also exposed to toxic chemical substances (e.g. soil insecticides), radionuclides (e.g. 137Cs), soil pathogens (e.g. saprophytic fungi) and soil parasites (e.g. hookworms). Inhalation of airborne dusts causes respiratory trouble (e.g. asthma). Many of the complex interactions between soil and human health are yet to be unveiled. For thorough understanding of the soil ecosystem and its relation to safe and nutritious food production and broadly human health, multidisciplinary approach is needed. Contributions of experts from agriculture, medical and social science fields are needed to address the whole soil and human health issues.