Drinking water quality
Assessment made on 13 Oct 2003
ClassificationWater (Primary theme)
- WEU 010
Policy issue: Do present day concentrations of hazardous substances have unacceptable impacts on human health and the environment?
The Drinking Water Directive (80/778/EEC), and its successor (98/83/EC which comes in force in 2003), aims to ensure that water intended for human consumption is safe. In addition to microbiological and physicochemical parameters, a number of toxic substances such as pesticides, polyaromatic hydrocarbons, cyanide compounds, and heavy metals are to be monitored. This is because the raw supply may be contaminated, for example, with pesticides from agricultural land which have leached into groundwater or from contamination within the distribution system, such as lead from piping. Some problems with pesticides and/or heavy metals in drinking water have been identified in national reports and by the European Union of National Associations of Water Suppliers and Waste Water Services (Eureau) (Map 4.4).
Pesticide pollution of drinking water has been identified as a problem in Belgium, Denmark, France, Germany, the Netherlands and the UK (Eureau, 2001) where it is estimated that between 5 and 10 % of resources are regularly contaminated with pesticides in excess of 0.1 µg/l. For example, in Germany in 1995, 10 % groundwater monitoring stations exceeded 0.1 µg/l particularly for atrazine despite its ban in 1991. One of the main causes of metal contamination of drinking water is from lead plumbing. For example, in France, extensive replacement of lead pipes is still required and in the UK, the use of lead solder is still common even though it has been illegal since 1987. In some of the accession countries, there are also problems with lead and other metals, for example, in the Czech Republic, barium and nickel are at levels that are of concern in some supplies and the Slovak Republic has recorded some high cadmium concentrations.