Copper in drinking water supplies and gastrointestinal illness in England and Wales: a risk assessment

This paper examines possible health risks from copper in drinking water supplies in England and Wales, with particular reference to gastrointestinal illness. This is done within the standard risk characterisation model, coupled with the use of an outline quality audit framework to examine the strength of the findings. The hazard source is identified in terms of naturally occurring and anthropogenic contributions, leading to monitored levels of copper in drinking water supplies. Dose response is estimated from scientific evidence for gastrointestinal effects from copper ingestion. Exposure is estimated by extrapolation from available data. It is shown from the overall risk characterisation that there is a 1 in 17,000 probability of exposure to levels of copper above 3 mg/l. Of the population exposed to elevated copper levels in their drinking water, 20% are likely to become ill. The outline quality audit ratings provide guidance on interpretation of these findings.