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Section 2 Architectural Planning
plastics, are relatively safe for use, but are toxic
during their production and again when they are
disposed of. Their production and incineration
produces dioxins, which are some of the most car-
cinogenic (cancer-causing) agents known.
Dioxins and heavy metals are known as
persistent bioaccumulative toxicants (PBTs).
These items do not break down quickly. They
can last for many years or even decades. Bioac-
cumulative means that they build up, or accu-
mulate, in living organisms. They can enter
your body through the air you breathe, the food
you eat, or even the soil you touch. Not only are
PBTs toxic, but many of them have been known
to cause mutations and reproductive disorders.
Relatively green alternatives to PVC include
polypropylene, polyethylene, and some thermo-
plastics. See Figure 11-8. In the future, possibly
the best choice will be to use a sustainably grown
bioplastic, which not only removes the toxicity,
but also helps reduce our dependence on the
petroleum that is used in traditional plastics.
Sustainably grown bioplastics are not widely
available yet; they are still in the research stage.
Other toxins that are commonly found in
building materials include volatile organic
compounds (VOCs). These chemicals contain
carbon compounds that vaporize at room tem-
perature. We then breathe in the vapor, which
often contains known carcinogens such as
formal dehyde, toluene, xylene, and benzene.
VOCs also contribute to smog and other envi-
ronmental hazards.
VOCs are commonly present in composite
woods, insulation, fl ooring, paints, and adhe-
sives, among other sources. Read the label
carefully when choosing these products. Try to
choose low- or no-VOC products as much as
possible. See Figure 11-9.
Semi-volatile organic compounds (SVOCs)
are similar to VOCs, but they release vapor
much more slowly. Whereas VOCs are most
hazardous during installation and shortly after,
SVOCs are released from building materials for
much longer periods. SVOCs are commonly
Figure 11-8. Polypropylene is one alternative to
PVC for plumbing applications. (Maryunin Yury
Vasilevich/Shutterstock.com)
Figure 11-9. This reclaimed Douglas fi r fl ooring
was treated with a low-VOC fi nish at the factory.
It is considered a sustainable product because it is
both reclaimed and free of harmful levels of volatile
organic compounds. (Viridian Reclaimed Wood)