Soil pollution implies the presence of chemicals and materials in soil that have a significant adverse effect on any organisms or soil functions. Soil pollutants include inorganic and organic compounds, some organic wastes and the so-called “chemicals of emerging concern”. Soil pollution has a direct impact on food security and there is a direct link between the quality and safety of the food we eat and the level of soil contaminants. Additionally, soil pollution affects food availability by reducing crop yields due to toxic levels of contaminants that hamper crop growth and reduce soil biodiversity, thus increasing the problem of food security.

Soil acts as a filter and buffer for contaminants, but its potential to cope is finite. If the capacity of the soil to mitigate the effects of contaminants is exceeded, the soil turns into a time bomb that can pollute other compartments of the environment. Soil pollution also triggers a chain of soil degradation processes, starting from the loss of soil biodiversity, the reduction of soil organic carbon, to the destruction of soil structure and the increase of soil erodibility. Contaminants can leach into groundwater or become available for plant uptake and entry into the food chain. Contaminants accumulate in plant tissues and soil organisms, passing to grazing animals, birds, or to humans that consume them. Many contaminants become more concentrated as they rise up the food chain, increasing the potential for harm to human health.

Combatting soil pollution requires a sustained effort to prevent further issues and to mitigate existing pollution. Promoting sustainable agricultural practices, asking governments to develop policies to reduce the use of harmful chemicals and to prevent and control soil pollution are actions that can be taken now. The Voluntary Guidelines for Sustainable Soil Management include integrated pest management as an important best practice. The International Code of Conduct on Pesticide Management and the International Code of Conduct on the Sustainable Use and Management of Fertilizers provide internationally recognized standards for the safe and judicious use of pesticides and fertilizers.