A closer look at PVC

SAN FRANCISCO -- What is PVC? Polyvinyl chloride is one of the most common forms of plastic. About 15 billion pounds is produced in the United States each year, about 70 percent of which ends up in building products such as plastic pipes, electrical insulation and vinyl flooring. Some PVC products get a pliable or soft consistency through the addition of chemicals such as phthalates.Environmentalists say PVC creates health and safety problems, including:-- Manufacturing. Vinyl chloride, the basic building block of PVC, is classified as a carcinogen by the U.S. Environmental Protection Agency. Vinyl chloride has been detected in the air around PVC manufacturing and disposal sites, and studies have linked work in PVC factories with liver cancer. -- Additives. Exposure to phthalates may affect the reproductive system, increasing infertility and reducing sperm count. Phthalates have also been linked to asthma and respiratory disease. -- Disposal. Incinerating PVC products can release toxic chemicals such as dioxin into the air, and burying them in landfills presents risk of leaching phthalates into groundwater. Some skeptics say that the dangers of PVC are being overstated due to "plasticophobia," and that PVC and vinyl present little risk to individual consumers -- particularly in items such as office products."I know of no study which demonstrates how a PVC binder could pose a threat to anyone's health by virtue of it being used as a binder," wrote Trevor Butterworth, an editor with STATS, a nonprofit group that aims to improve the quality of scientific information in the media, in an e-mail. "You might be able to ingest some tiny amount of chemicals if you spent the day licking the binder, but even then, there is no reason to think that even such extreme behavior would make you sick or pose a risk to your health."But other observers say that the risk isn't from a single item as much as from cumulative exposure to thousands of items over time."The nature of the problem for children, in particular, is that they encounter multiple sources for many of these chemicals," wrote James Leckie, an environmental chemistry professor at Stanford University, in an e-mail. "Exposure comes from multiple pathways: dermal, inhalation (chemicals on dust particles), and ingestion .... There are very few studies which evaluate the critical aspects of these issues. Often industrial representatives will tell you there are no data supporting the environmental concerns. Many times they are right because there are no appropriate studies and hence no data."E-mail Ilana DeBare at idebare(at)sfchronicle.com.(Distributed by Scripps Howard News Service, www.scrippsnews.com.)