Many pesticides pollute drinking water, the most common being atrazine and simazine (although the source of these is likely to be runoff from parks and roads).

The EU Directive on Drinking Water came in to effect in 1985 and requires the nitrate level in water not to exceed 50 mg/litre. This is 5X the level recommended by the WHO in 1984. Nitrates in water are recognised by the government to create risks of stomach cancer and "blue baby syndrome"

According to the UK Dept of Environment Co-ordination group nearly one million people would be exposed to drinking water above this level. The costs of clean up are between £100 - 200 million. They suggest blending better quality water with poorer quality and recommend altering planting and spraying patterns.

The 1991 EU Directive 91/676 "concerning the protection of waters against pollution caused by nitrates from agricultural sources", aims to reduce and prevent pollution of fresh surface water, estuarial and coastal water caused by nitrates from diffuse sources. Member states must identify vulnerable zones and produce action programmes to deal with them.