Pesticide fate and behaviour in Australian soils in relation to contamination and management of soil and water: a review

Pesticides, if used as recommended, are generally expected to cause little adverse impact on the environment. However, it is evident that trace levels of pesticide residues present in soil, water, air, and sometimes food, may result in harmful effects on human and environmental health. Pesticides can pose health risks through several exposure pathways including direct occupational related exposure, through food, or through the residues present in the environment. This paper reviews available information on the nature and extent of pesticide contamination of Australian soils, surface water, and groundwaters. Published studies on the fate and behaviour of pesticides in Australian soils have also been reviewed, covering the key processes controlling the fate and behaviour of pesticides in soils, namely sorption-desorption, degradation (biological and abiotic), and volatilisation in soil and their off-site transport into surface and groundwaters. Some management options for minimising the diffuse source pollution of soils and waters by pesticides and remediation of contaminated soils and water have also been discussed. The review concludes that contamination of soils and water with pesticides has occurred in Australia and there is a need to understand the behaviour of pesticides in the soil environment in order to develop management practices to minimise any adverse impact on our environment in future.