Recycling & Environment # 2006 Washington DC
The possible effects of plastics pipes on drinking water quality are frequently in discussion and require the highest attention of our industry. On one hand, the European Commission (EC) is working already long time to set up a European Acceptance Scheme (EAS), so far without the desired speed. The Plastic Pipe industry is intensively involved in these developments and is concerned on the lack of realism in the draft proposals. New test methods are still under development (Biofilm formation and GC-MS) where Teppfa doubts whether this can anyway result in a workable test procedure with realistic requirements. In this context also the measuring of reaction products (mainly in PE and PEX) is a new issue that will probably be taken on board. Furthermore, existing and frequently used tests showed an unacceptable spread in results between different laboratories. On the other hand, plastics pipes came in negative publicity due to assumed migration of phenols from different origins and other substances. After the publication of professor Arvin in Denmark and the political rumour, a new investigation has been initiated by the Danish industry in co-operation with the authorities, with the aim to verify the detected substances in a realistic field test programme. The results of this study were positive for our products. The Danish study concluded that there is no health risk due to migrating substances from PVC and PE distribution pipes as they are functioning in practise. All substances that were reported by Arvin some years ago, were in practise measured at very low concentrations or even mostly not detectable. Also the focus on biofilm growth and its possible effects on legionella growth are frequently highlighted, suggesting that plastics stimulate its growth where e.g. copper reduces the risks. There is evidence that at long term all pipe materials behave in a similar way, and a recent study even shows that copper performs even worse than plastics.