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Perchlorate - risks to UK drinking water sources - WT1206

Perchlorate has been detected in many drinking water sources in the US. It is estimated that about 11 million people may receive water containing more the 4ìg/l.

Perchlorate is known to inhibit the function of the thyroid but there is uncertainty over the toxicological significance of the perchlorate levels found. No guideline value has been set by the WHO nor has standard been set by the USEPA. A preliminary risk assessment conducted by the USEPA in 2002 implied a standard in the low microgram per litre level may be appropriate. However during the 2005 a review by the US National Research Committee implied that a standard at about 20ìg/l would be more appropriate.

Perchlorate can occur naturally and it is an impurity in some forms of nitrate fertiliser, however the main source is thought to be from disposal of rocket fuel. It seems unlikely that there will be significant contamination of UK drinking waters. The Inspectorate is not aware of any monitoring in the UK. The purpose of this research is to assess the risks to UK sources based on usage etc and conduct some targeted monitoring to determine levels found and confirm the risk assessment.
Project Documents
• Final Report : Perchlorate - risks to UK drinking water sources   (994k)
• Executive Summary : Perchlorate - risks to UK drinking water sources.   (35k)
Time-Scale and Cost
From: 2007

To: 2009

Cost: £79,090
Contractor / Funded Organisations
WRc plc
Drinking Water              
Water Quality              
Fields of Study
Water Quality