Contaminants threatening the health of soil and water

The fouling of fresh water supplies with pollutants emanating from primary agriculture has become a serious issue in South Africa. In this article, the Agricultural Research Council discusses the origins and impact of so-called contaminants of emerging concern.

Most processes in agriculture use chemical intervention either to boost plant or animal production or to prevent or treat diseases. Whilst such chemicals may be necessary to achieve desirable farming results and thereby help ensure food security, they can contribute to contamination of the environment. Contaminants of emerging concern (CECs) have recently been highlighted as a priority problem in South Africa’s freshwater ecosystems.

WHAT ARE AGRICULTURAL CONTAMINANTS?

CECs are best described as unregulated, synthetic or naturally occurring chemicals, particles or micro-organisms commonly found in surface water resources, as well as the environment in trace amounts. They are not typically detectable or monitored. Agricultural CECs are contaminants that originate from agricultural inputs such as inorganic fertilisers, pesticides, herbicides, fungicides and hormones. These inputs are increasingly used in agriculture to increase livestock production, crop quality and yield.

Soil health decline and infringement on farming lands have put strain on the availability of food resources to sustain the world’s growing population. Population growth is fuelling the increasing demand for food and water due to the number of people exceeding resource availability. This has put pressure on the agriculture sector to use a number of inputs to improve yield and output.