Drinking Water Quality
Assessment made on 01 May 2004
ClassificationWater (Primary theme)
- WEU 010
Policy issue: What are the main problems in drinking water quality? Are we meeting the standards of the Drinking Water Directive?
In the EU15 countries nitrate contamination is a problem commonly identified in many national reports. This is likely to be due to intensive agriculture and the use of artificial fertilisers which contaminate raw water sources. Nitrate contamination is often a particular problem in small wells e.g. in Belgium 29% of 5000 wells examined had nitrate levels in excess of 50mg/l nitrate (OECD EPR Belgium, 1997). Excess nitrogen in drinking water is of particular concern for babies where it is known to cause methemoglobinemia, or "blue baby" syndrome. It is also often a particular problem in rural water supplies, which are not necessarily reported or well monitored since they often only serve small populations and are not covered by the drinking water directive. However, nitrate contamination should be reduced with the implementation of the Nitrates Directive ((91/676/EEC).
In the Central and Eastern European countries (CEEC) problems with microbiology (e.g. in Slovakia and Hungary) and nitrates (e.g. in Estonia) were also reported. However, the most common problem across the CEEC was metal contamination. For example, the Czech Republic has problems with barium, nickel and selenium (OECD EPR Czech Republic, 1999) and in Lithuania 55% of samples from centralised sources have excess iron (CEETAC, 2000). Problems with iron and manganese are common in Central and Eastern European countries due to lack of efficient technologies installed for removal of these contaminants which often occur naturally in groundwater. In addition, Slovakia and Hungary had high exceedences for the toxic parameter arsenic. The sources of arsenic in drinking water are from the water flowing through arsenic rich rocks and also from industrial contamination. Long-term exposure to arsenic contamination causes various skin diseases and also cancer of the skin, lungs, urinary bladder and kidneys (WHO, 2001).
The main problem in the Newly Independent States is microbiological contamination of drinking water due to decaying infrastructure e.g. water treatment works that are no longer functioning properly and the prohibitive cost of chlorine which is needed to treat the water. For example in Armenia, 90% of pipes are more than 10 years old and 60% are more than 20 years old (SoE, Armenia, 1998). Contamination from toxics and nitrates was also evident from national reports.