Health Stream Literature Summary - Issue 58 - June 2010

Is there still a problem with lead in drinking water in the European Union?
Hayes, C.R. and Skubala, N.D. (2009) Journal of Water and Health, 7(4); 569-580.

Lead was commonly used for plumbing in European Union countries until the 1980s, but in recent decades the health risks of exposure, especially in infants and young children, has been recognised. The adverse health effects of lead include: interference with haem biosynthesis, interference with calcium and vitamin D metabolism, gastrointestinal irritation, dullness, restlessness, irritability, poor attention span, headaches, muscle tremor, abdominal cramps, kidney damage, hallucination, loss of memory, encephalopathy, hearing impairment, gonad dysfunction and violent behaviour. Possibly the greatest health concern associated with lead is reduced IQ in infants. Lead pipes are the major source of lead in drinking water but lead can also be released from other lead components, sub-quality brass fittings, led solder and PVC treated with lead stabilisers. Lead in drinking water is more readily absorbed in the intestine than lead from dietary sources. Infants and foetuses are the most susceptible groups to the adverse health effects of lead as they absorb 4 to 5 times more lead than adults and the biological half-life is considerably longer.

Drinking water regulations in England and Wales require 98% compliance with the EU standard of 10 microg/l, and orthophosphate treatment of public water supplies to reduce plumbosolvency is now widespread. However in most other EU countries there has been little corrective action to reduce lead in the drinking water. In some cities lead mains pipes have been progressively removed but lead pipes still exist within many homes. Most EU countries are reluctant to dose ortho-phosphate in their water supplies due to philosophical or environmental concerns. Data on lead concentrations at household taps are very limited, and the Member States within the EU have failed to agree on a common monitoring method for lead at household taps. A number of different sampling methods are used in the EU to determine compliance for lead, and some of these are inappropriate for assessing human exposure. Random daytime (RDT) first-draw sampling from consumers' taps is regarded as an appropriate representative method that is logistically feasible for assessing exposure to lead in drinking water in a water supply zone (e.g. a city or town), if enough samples are taken. Split-flow composite (COMP) sampling has been used for the direct measurement of weekly average lead concentrations in drinking water (each time the tap is opened to draw drinking water, a small part of the flow is taken for collection in a sample container). COMP is the most reliable method for investigating lead levels in individual dwellings however it is not feasible logistically for use as a large scale survey tool.

Emerging data indicates that many water supplies in the EU still have a lead problem and will have difficulty meeting the EU standard of 10 microg/l when it becomes a legal requirement in 2013. It has been estimated that about 65% of dwellings with lead pipe, either as a connection pipe or as internal piping, are likely to exceed the standard, unless corrosion inhibitor is correctly dosed into the water supply. Data on the occurrence of lead pipes in the EU is poor but it has been estimated that about 25% of houses have some lead piping, putting a potential 120 million people at risk. In some cities however, the percentage of houses affected will be much higher. Since 1989, RDT sampling has been used in the UK to assess compliance with lead at the consumers'; taps and in recent years many of the UK water companies have increased their monitoring frequencies for lead as part of a UK Government prompted plumbsolvency control campaign. Samples for lead analysis were taken at the same locations being sampled for bacteriological parameters. Such increased sampling for lead is logistically feasible and will add little to the cost if linked to bacteriological sampling visits to consumers' dwellings.

The World Health Organization (WHO 2004) has advocated the adoption of drinking water safety planning; a proactive approach for hazard identification, risk assessment and risk management. To ignore the risks associated with lead in drinking water would be entirely inconsistent with this recommended safety planning approach.

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