With increasing reports of old PVC pipes leaching toxic vinyl chloride into a number of rural drinking-water systems, trade groups are working to plug leaks in vinyl's environmental image.
Vinyl chloride monomer has been traced to PVC pipes installed in two rural Kansas water systems during the late 1960s and early 1970s. And officials in other Midwestern states are poised to begin testing for the cancer-causing substance in similar systems beginning this summer.
Regulators on April 14 reported finding VCM in a water system serving 480 customers in rural Russell County, Kansas, and surrounding areas.
The findings in Russell mark the second time the chemical has been found in a Kansas water system.
Tests first linked vinyl chloride to pipes in the Doniphan County Rural Water District No. 5 near Troy, Kansas, in 1992, according to Dave Waldo, chief of the Public Water Division of the Kansas Department of Health and Environment. Traces of VCM first turned up in a neighboring water system in 1989, Waldo said in an April 17 telephone interview. A series of tests isolated the pipes in RWD No. 5 as the source.
Industry groups first offered to help detect and reduce VCM in 1994, but there was little support for such an effort by federal regulators — or local customers, Waldo said.
In 1997, Greenpeace mentioned the Kansas water situation in its broader campaign against chlorine chemistry. A Kansas City newspaper then picked up on the story, spurring wider action, Waldo said.
Since then, regulators and trade groups have been working on ways to fix the systems where VCM has been detected and to sniff out other systems where unacceptable levels of the chemical can be found in drinking water.
The problem can be traced to the way PVC resins were made before regulators tagged VCM as a known carcinogen in 1975, said Tim Patterson, director of environmental solutions for PVC maker Geon Inc. of Avon Lake, Ohio, and point man for the Vinyl Institute on this issue.
Before 1975, the method PVC makers used to recover unpolymerized VCM from their resins ``wasn't as well-developed,'' Patterson said April 16. Various batches of PVC resin contained varying amounts of unpolymerized VCM.
Patterson said the industry picked 1977 as a conservative cutoff year for VCM testing just to make sure all later pipes would not have a VCM risk.
When the rural water systems installed pipes made from the pre-1977 resin, there was no hint of possible danger, said Robert Morby of the Environmental Protection Agency. Morby heads the Drinking Water/Ground Water Management Branch of EPA's Region 7 in Kansas City.
``Nobody ever envisioned vinyl chloride would ever be released from vinyl pipe,'' Morby said.
A special set of circumstances have to occur before VCM can be detected in pipes using the old-style resin.
``Three things have to happen,'' said David Eckstein, deputy executive director of the Uni-Bell PVC Pipe Association. ``The pipe not only has to be made prior to 1977, it also has to be high in vinyl chloride,'' he said from his Dallas office.
Eckstein added that not all resin made before 1977 was high in unpolymerized vinyl chloride.
``The water also has to have high contact with the pipe wall,'' he said.
That condition would occur most often in low-use pipe near the end of a system.
``High temperatures also are required at the time of testing,'' Eckstein said.
If any of those conditions are not present, the same pipe will test clean of VCM, he said.
Now that VCM has been detected in the old systems, industry groups are taking a leading role in abating the risk to water customers.
The Vinyl Institute already is shipping bottled water to 25 of 28 affected customers in RWD No. 5, Patterson said. The group has a draft agreement to provide replacement pipe, a carbon absorption system, or an automated flushing system to the district.
The problem may not end in Kansas, however. Systems in Iowa and Nebraska are scheduled for VCM tests this summer when levels are likely to be at their highest. EPA regional offices in Texas and California also have been notified about the potential risk. Those offices cover eight states.
VI has offered to pay for the testing of at-risk systems.
``They've been very open and willing to provide assistance,'' Waldo said of industry group involvement.
Vinyl chloride ranks fourth on the list of most-hazardous chemicals by the Agency for Toxic Substances and Disease Registry. The gas even has its own disease named after it — vinyl chloride disease. Regulators say lengthy exposure to vinyl chloride gas can cause a rare form of liver cancer as well as numerous other ailments.
VI, based in Morristown, N.J., is a unit of the Washington-based Society of the Plastics Industry Inc. Uni-Bell of Dallas is a VI affiliate.