Report No DWI0775

Feb 1997

In 1995, the European Commission published a proposal for a revised Drinking Water Directive (Council Directive concerning the quality of water intended for human consumption). Negotiations on the proposal have started in the Council of Ministers. The proposed, revised Directive has the same standard for total polycyclic aromatic hydrocarbons (PAH) as the existing Directive 80/778/EEC, ie. 0.2 µg/l for the total of six specified PAH, but has introduced a separate standard for benzo(a)pyrene of 0.01 µg/l. The requirements for monitoring will be more stringent than in the present directive, but generally in line with UK practice; samples will be taken at consumers' taps.

Contraventions of the standard for total PAH are occasionally observed in the UK; these are due to leaching of PAR (mainly fluoranthene) from old coal tar lined pipes still in use in distribution systems. In order to estimate the extent of similar problems and awareness of them in other EU Member States, contact was made with trade associations, pipe manufacturers, research institutes, and representative, regional or local authorities and water suppliers in all EU Member States, though the efforts focused particularly on the larger countries, Germany, France, Italy, and Spain.

Overall there does not seem to be much concern in other EU Member States over compliance with the PAH parameter. This seems to be partly due to a lack of information in general, in part to lack of end-of-pipe monitoring of PAH in drinking water, and in part to limited use of coal tar lined mains in the past. Clear evidence of problems with PAH as a result of the use of coal tar lined pipes has been obtained only from Germany; France may have some problems, but data do not seem to be available. Belgium also seems to experience some difficulty and isolated incidents were mentioned in Spain.

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