Testing the European waters

For the last three years, an independent organisation has also been using a panel of experts for their discriminating taste and smell to test drinking water from European plastic pipes. According to the panel, the drinking water is perfect. Next to panel assessments for taste and odour, an electronic nose is being designed that might well mimic the human olfactory system!

The technical organisation is called Kiwa, the Dutch Certification Body for Drinking Water. Since the 1960's, it has been testing materials in contact with drinking water. Kiwa experts are therefore involved in the harmonisation of standards for the European Commission (TC 164, 230 & 155) and The European Plastic Pipes and Fittings Association (TEPPFA).

Hans van der Jagt, scientific expert for this important technical work at Kiwa explains: "The drinking water that leaves a domestic meter should be as fresh as the drinking water that enters the pipe network. We do not expect to find the slightest hint of odour or bad taste." Currently the hygienic quality of drinking water in contact with materials is part of a specific certification procedure.

New and used plastic pipe samples are collected by Kiwa from all over Europe. For these pipes special analysis is undertaken to assess the quality. The pipes are filled with drinking water and left to stand for 3 x 72 hours under strict laboratory conditions. The three extracts are assessed by eight individual panellists. They are well trained and selected for blind testing of the samples.

"Our panellists carefully smell and then taste the water in a similar way to a wine connoisseur. Furthermore, we have a control batch containing undesirable organic compounds to make sure that we make a truly scientific comparison. Our experts can detect even the minute presence of organic material. In combination with panel testing, new developments are being carried out in the form of gas chromatography, time of flight and mass spectrometry (GCToFMS). We are therefore creating an electronic nose to confirm our judgement and check odour and flavour data."

Hans van der Jagt says that the drinking water collected from plastic pipe samples has passed all the human and electronic tests. The Kiwa organisation would now like to conduct more regular and wider European testing. However, this workload would involve a greater reliance on laboratory equipment. As yet and as far as taste and smell are concerned, the European Commission has to be convinced that humans are less discriminating than machines.


For further information:
Plastics Europe
Avenue E van Nieuwenhuyse 4
Box 3
1160 Brussels
Belgium
Phone: +32 (2) 675 32 97
Email: info@plasticseurope.org
Web: www.plastic-pipes.com