Consumer Concerns
Pesticides
Pesticides in drinking water are an extremely emotive issue that has been the subject of sustained environmental campaigns for over two decades. In England and Wales, however, pesticides in drinking water are no longer an issue because of the extensive water treatment processes introduced in the last ten years to remove them from drinking water supplies.
The 1980 European Community Drinking Water Directive set a standard of 0.1 microgramme per litre for each pesticide in drinking water. As this concentration was equivalent to the detection limits of analytical methods available at the time, this standard was effectively a zero concentration. The Directive also set a standard for total pesticides of 0.5 microgramme per litre. Both of these standards were included in our national drinking water regulations. The 1980 standards were retained in the 1998 revision of the Directive and therefore will be retained in our new national drinking water regulations.
Pesticides in water can be derived both from agricultural use and non-agricultural use, such as weed control on hard surfaces. Contamination events from production or transport of pesticides are rare. Non-agricultural uses include weed control on paved areas, road verges, golf courses and railway tracks. Over the last ten years, significant effort has been devoted to encouraging more careful use of pesticides.
As a result of enforcement action initiated by the Inspectorate since 1990, water companies have installed treatment processes to remove pesticides to ensure compliance with the standards. These processes involved the installation of advanced treatment technologies including oxidation processes using ozone and absorption processes using activated carbon filters. In 2006, 99.99% of nearly 350,000 tests for pesticides met the standards. Where any sample fails to meet the standard, action is taken by water companies in conjunction with their health advisors, to protect public health.
