Effect of organic compounds migrating from PE pipes on drinking water biofilms

Polyethylene (PE) pipes are often the chosen material when commissioning new drinking water pipes in Denmark. Previous studies have identified numerous compounds leaching from PE pipes to drinking water. Here, the effect on enrichment cultures of young (8 weeks, FRE) and old (6 years, BUS, TBR) PE pipe biofilms were studied with a) 9 selected compounds known to migrate from PE pipes and b) a natural “PE-cocktail” obtained from crushed PE pipe. The 9 pure compounds had a limited effect on biofilm growth from BUS and TBR, while the growth and activity of FRE biofilm was stimulated. The PE-cocktail stimulated activity of biofilms, and increased biofilm formation in BUS and FRE enrichments. These results highlight potential beneficial effect of biofilms on the distributed drinking water quality.