New research is calling for immediate safeguards and the study of a widely used method for repairing sewer-, storm-water and drinking-water pipes to understand the potential health and environmental concerns for workers and the public.
The procedure, called cured-in-place pipe repair, or CIPP, was invented in the 1970s. It involves inserting a resin-impregnated fabric tube into a damaged pipe and curing it in place with hot water or pressurized steam, sometimes with ultraviolet light. The result is a new plastic pipe manufactured inside the damaged one. The process can emit chemicals into the air, sometimes in visible plumes, and can expose workers and the public to a mixture of compounds that can pose potential health hazards, said Andrew Whelton, an assistant professor in Purdue University’s Lyles School of Civil Engineering and the Environmental and Ecological Engineering program.
He led a team of researchers who conducted a testing study at seven steam-cured CIPP installations in Indiana and California. The researchers captured the emitted materials and measured their concentration, including styrene, acetone, phenol, phthalates and other volatile (VOC) and semi-volatile organic compounds (SVOC).
Results from their air testing study are detailed in a paper appearing on July 26 in Environmental Science & Technology Letters. The study files can freely be downloaded and are open-access, and the paper is available at http://pubs.
Findings show that the chemical plume, commonly thought of as harmless steam, was actually a complex mixture of organic vapor, water vapor, particulates of condensable vapor and partially cured resin, and liquid droplets of water and organic chemicals. A YouTube video is available at https:/
“CIPP is the most popular water-pipe rehabilitation technology in the United States,” Whelton said. “Short- and long-term health impacts caused by chemical…