Toxicity of the Pyrolysis and Combustion Products of Poly(Vinyl Chlorides): A Literature Assessment.
Toxicity of the Pyrolysis and Combustion Products of
Poly(Vinyl Chlorides): A Literature Assessment.
(8178 K)
Huggett, C.; Levin, B. C.
NBSIR 85-3286; 48 p. April 1986.
Fire and Materials, Vol. 11, No. 3, 131-142, September
1987.
Sponsor:
Consumer Product Safety Commission, Washington, DC
Available from:
National Technical Information Service
Order number: PB86-201621
Keywords:
carbon monoxide; combustion products; hydrochloric acid;
large scale fire tests; polyvinyl chloride; pyrolysis
products; small scale fire tests; toxicity; thermal
decomposition
Abstract:
Poly(vinyl chlorides) (PVC) constitute a major class of
synthetic plastics. Many surveys of the voluminous
literature have been performed. This report reviews the
literature published in English from 1969 through 1984
and endeavors to be more interpretive than
comprehensive. PVC compounds, in general, are among the
more fire resistant common organic polymers, natural or
synthetic. The major products of thermal decomposition
include hydrogen chloride, benzene and unsaturated
hydrocarbons. In the presence of oxygen, carbon
monoxide, carbon dioxide and water are included among
the common combustion products. The main toxic products
from PVC fires are hydrogen chloride (a sensory and
pulmonary irritant) and carbon monoxide (an asphyxiant).
The LC50 values alculated for a series of natural and
synthetic materials thermally decomposed according to
the NBS toxicity test method ranged from 0.045 to 57
mg/l in the flaming mode and from 0.45 to > 40 mg/l in
the non-flaming mode. The LC50 results for a PVC resin
decomposed under the same conditions were 17 mg/l in the
flaming mode and 20 mg/l in the nonflaming mode. These
results indicate that PVC decomposition products are not
extremely toxic when compared to those from other common
building materials. When the combustion toxicity (based
on their HCl content) of PVC materials is compared to
pure HCl experiments, it appears that much of the
post-exposure toxicity can be explained by the HCl that
is generated.
