Making vinyl and other plastics releases dangerous pollutants. Do they belong in green buildings?
PVC, often called vinyl, has long been controversial in the sustainable design and green building worlds. It’s red-listed in the Living Building Challenge and the Cradle to Cradle certification system, and the attempt by the LEED people to limit its use in buildings almost brought down the whole certification system.
PVC is made from two main ingredients: 43 percent fossil fuels, and 57 percent salt. At TreeHugger we have worried about the former, but a devastating new report from the Health Building Network concentrates on the latter. The industry often presents the salt as a benign, natural material, which it is until they put high voltage through it to split it into chlorine and sodium and then force it through an asbestos diaphragm to separate it.
Then it is a whole different picture. the HBN writes:
- Chlorine is inherently highly toxic.
- Chlorine production uses and releases mercury, asbestos, or other highly toxic pollutants. (Mercury use has significantly declined, but the US still imports 480 tons of asbestos per year for diaphragms, primarily from Russia.)
- Combining chlorine with carbon-based materials creates environmental health impacts that are difficult if not impossible to solve.
PVC contains nearly 60% chlorine by weight, and most PVC is manufactured for use in building products. Indeed, chlorine and building industry analysts agree that because building trends drive PVC demand, and PVC demand drives chlorine production, it can fairly be said that the building-products industry drives chlorine production levels and its attendant environmental and human health impacts.
PVC is essentially a solid mix of oil and chlorine, yet it is still such a big part of building, the main component of pipes, siding, flooring and roofing. It’s also in epoxies and polyurethane; according to HBN, their production consume most of the world’s chlorine.
Over a quarter of the world’s PVC resin, ethylene dichloride (EDC) and vinyl chloride monomer (VCM) is made in refineries on the US gulf coast, located there because of the availability of salt and electricity. A third of it is shipped to China, from whence it returns as finished PVC and plastic goods like vinyl flooring.
Chlor-alkali plants release many pollutants, including chloroform, dioxins and PCBs, not to mention releases of the toxic products themselves: chlorine, VCM and plastic pellets. "Chlor-alkali facilities are major sources of rising levels of carbon tetrachloride, a potent global warming and ozone depleting gas, in the earth's atmosphere."
Jim Vallette, HBN Research Director and lead author of the report, says in a press release:
This report is a prerequisite to understanding the origins and life-cycle impacts of high-volume building materials such as polyvinyl chloride, and others including polyurethane, and epoxies. When we know better, we can do better to reduce the environmental and health impacts of this material through the supply chain.
But the report only covers the 57 percent of PVC that is the chlorine. It doesn’t get into the massive increase in plastics production planned by the oil companies, who are spending $180 billion on new cracking plants to make ethylene and other feedstock chemicals. It doesn’t discuss the dangers of the products, due to the phthalates and stabilizers. It doesn’t go into the end of life issues.
Add these to the questions raised in this report, and you have to ask why anyone would use this stuff. PVC had been creeping back into green building; Green icon Interface now offers vinyl flooring, and more affordable PVC windows are going into Passive House designs. After reading this report, it is time to reconsider, and to reiterate: Plastics do not belong in green building.
Download Phase 1 of the report from the Healthy Building Network. It only covers Africa, the Americas and Europe; I suspect Phase II will be even scarier.