Vinyl: Any Color but Green
"This is neither rigorous science," Braungart replied, "nor an unprecedented report. The quality of the work is actually quite poor. The analysis is not even consistent with the claimed methodology. Key components are missing. It is common knowledge, for example, that PVC needs high quantities of lead as a stabilizer, but [there's] not one word in the report about lead, nor about organotin compounds. Tons of mercury from chlorine plants — not factored."
Vinyl — Blue or Green?
The problems with PVC begin in its production. The documentary film "Blue Vinyl" focuses on workers who contracted cancer after being exposed to vinyl chloride and dioxin; both are produced in making PVC and are strong carcinogens. The industry asserts that recent measures have reduced exposure to these chemicals to acceptable levels.
There are also dangers to those who live near vinyl production facilities. A front-page story in the New York Times reported in 2003 that a trailer park housing 300 residents in Plaquemine, Louisiana was forced to close after by-product vinyl chloride was discovered poisoning the aquifer. Residents there have reported an excessive number of miscarriages.
Additives known as phthalates are blended into PVC to make it softer and more pliable for materials such as coatings for wiring. Vinyl industry spokesman Tony Sain goes to great lengths to show that phthalates are not carcinogenic. However, the primary problem with phthalates has been shown to be DNA damage, and they are particularly harmful to the male reproductive system.
"The problem with phthalates and other additives in PVC is that they are not strongly bound to the polymer," says Jason Avent, a biological researcher for the Center for Maximum Potential Building Systems. This "loose" mixture allows phthalates to migrate to the surface and into the air. A new PVC shower curtain, for example, can affect indoor air quality for up to a month.
Vinyl on Fire
What happens to PVC when it burns is also disturbing. Chlorine gas is emitted because PVC is often more than 50 percent chlorine. When that gas comes in contact with moisture in eyes, throats, or sprinkler systems, a concentrated form of hydrochloric acid forms. This is essentially the same as the chemical weapon that was so devastating in World War I. Braungart asserts: "The consequences of fires alone should be enough for green architects to reject the product."
"Unfortunately, the organochlorides formed when PVC burns are narcotic compounds," Avent says. "This means that on top of thick smoke and stinging acid, they also can impede your mental ability to get to a door." He cites the paper, "The Use of Plastic and other Non-Metallic Materials at CERN with respect to Fire Safety and Radiation Resistance," available as a PDF file download.
The vinyl industry's defense focuses on dioxin levels in burning PVC.
"...All burning building materials emit toxins (sometimes including dioxin); which is why firefighters are encouraged to wear oxygen masks," Tony Sain says. "Further, it is probably safe to say that our courageous firefighters have more pressing concerns when they enter a burning building than the chemical composition of the smoke."
But because of that toxic plume, many firefighters and the International Association of Firefighters support alternatives to PVC in building materials.
Disposing of PVC also has its risks. Burning the material can release dioxins and other hazardous chemicals. Harmful additives such as phthalates and heavy metals can leach out of the roughly 1.5 million tons (1.4 million metric tons) of vinyl discarded each year just in the United States. Often landfills are unlined so that harmful materials can find their way into ground water. Of the landfills that are lined, many use a liner made of... PVC!
PVC is difficult to recycle. The Healthy Building Network estimates that only 0.1 to 3.0 percent of discarded PVC is actually recycled. It also poses a risk of contaminating other recyclable plastics with chemicals and heavy metals.
Alternatives to PVC
In our market-driven economy, a key factor that makes PVC so pervasive is its low cost. A recent Tufts University study on phasing out PVC found that one important reason for its low cost is that it is produced in massive quantities. Alternative materials could be more competitive if they had a larger share of the market.
Moreover, the Tufts study found that when overall lifecycle costs were considered, many materials came out ahead of vinyl. A California State Department of Health study shows that linoleum, made from natural linseed oil — naturally antibacterial and biodegradable — has lower VOC emissions than vinyl — although these emissions are not as low as those from other products such as cork.
A large portion of the world's production of PVC goes into making pipe — often used to carry water supply and waste. Copper is preferred for supply pipes, but polyethylene (PE) pipe is becoming an inexpensive and more environmentally friendly alternative to PVC.
PE pipe is lightweight like PVC, its joints are more leak-proof, it's stronger in high-pressure applications, and it withstands cold temperatures without getting brittle — a weakness of PVC. For hot water, the more expensive cross linked polyethylene (PEX) is used. Its cost is offset by installation savings because polyethylene is very flexible. It can turn corners and wind its way through framing with fewer joints.
Another common application for PVC is the insulation around wiring. Companies such as Houston Wire are producing halogen-free cable. Halogens are a family of highly reactive, often toxic elements that include the chlorine found in PVC as well as bromine found in bromine fire retardants (BFRs).
The Debate Continues
The vinyl industry claims that environmentalists are waging an irrational campaign against a safe and inexpensive material. They have shown significant progress in protecting workers from exposure to toxic materials during manufacture.
But scientists like Braungart accuse vinyl manufacturers of waging a classic "tobacco industry" type campaign: "The manufacturers fund universities to conduct controversial research. So long as there is controversial research, there is not enough evidence to justify any action. There is no liability problem, and the researchers are kept happy. It is a toxic coalition in every sense of the word."
As with many modern debates, architects are faced with the task of sorting the hyperbole from the facts in specifying materials. Regardless of the stand of the USGBC, the fact that there are serious health and environmental concerns at every phase in the life cycle of PVC should be enough to direct architects toward safer alternatives.
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Michael Cockram is an adjunct assistant professor of architecture at the University of Oregon. He is the director of the Italy Field School Program.