Abstract: Water pipes of high-density polyethylene (PE-HD)，crosslinked polyethylene pipes (PE-X)，and rigid polyvinyl chloride) (PVC-U) were tested with respect to migration of volatile organic components ( VOC) into water. the odour of water in contact with plastic pipes was assessed according to the quantitative threshold odour number (SON).the major migrating component from PE-HD pipe was 2，4-di-tert-butyl-phenol (2，4-DTBP) which is a degradation product from phenol antioxidants. In addition, esters, aldehydes, ketones, aromatic hydrocarbons, and terpenoids were identified as migrationproducts from PE-HI)pipe. Water in contact with 5/7 PE-HDpipe was assessed as TON≥4.A significant amount of VAC migrated from PE-X pipe into water with TON≥5，some of the migrated VOC were not identified. In contrast, PVC-U pipes released few volatile migrants into water, from which no obvious odour detected.

Key words: plastics water pipe, volatile organic component, migration