PVC Toxicity and Sustainable Materials

I read with interest and concern your article on Plastics in Construction (

Vol. 10, No. 7/8). As always, EBN goes out of its way to present an even and fair picture of the issues and alternatives. Emphasis in the article was on alternatives and LCA, which are important areas for exploration. I think, however, that in this case, you were a bit too easy on the worst of the plastics, PVC. It isn’t the worst just because it is the most common plastic in building, but because of the multiple toxicities it presents. As you point out, vinyl chloride itself is a carcinogen, and the phthalates that PVC contains are indicted as both carcinogens and hormone disruptors. Dioxin, produced when PVC is burned and when it is produced, is one of the most toxic chemicals known. When PVC burns, hydrogen chloride is created, deadly to occupants and firefighters because it is colorless and heavier than air. Because PVC is so friendly to additives, there are lots of added undesirable materials such as lead and cadmium, which may actually leach out of the plastic. We have banned lead paint, only to replace it with lead from vinyl siding.

As I say, you have mentioned most of these issues but failed to discuss the seriousness of the threat to human health, that of other species, and global health. Dioxin, for example, has already reached health threatening levels in most adults and children in the world. Phthalates are also bioaccumulative; the body can't clean them out, so the levels just get higher and effect reproductive and genetic disorders. The victims don’t have any choice; the spread of these chemicals is worldwide. Those highest on the food chain are most at risk: nursing babies, children, and large mammals get the strongest doses.

In past building projects, I have made an attempt to discourage the use of PVC because I had the idea that it wasn’t a good thing. More recent information convinces me that this is a one of the most serious problems for long-term sustainability and human health. We have to eliminate persistent toxic chemicals that build up in the environment. We'll work much harder to eliminate it and substitute safer products in the future, and I hope

EBN will encourage its readers to do likewise.

Mark E. Kelley III, PE

Building Science Engineering

Harvard, Massachusetts