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By Kim Gifford
When choosing materials for a building project, a
variety of factors come into play — cost,
durability, availability and the safety of the
material itself. Determining whether a material is
safe can be difficult, especially if the material in
question is as hotly contested as polyvinyl chloride
(PVC).
The Debate
PVC is a synthetic material formed from 57 percent
chlorine and 43 percent ethylene (oil). The ethylene
and chlorine combine through chemical reaction to
form ethylene dichloride, which in turn is
transformed into a gas called vinyl chloride monomer
and subsequently into polyvinyl chloride. PVC was
first developed for the military in World War II and
began appearing in commercial use in the 1960s.
Widely used in the construction industry, the safety
of PVC has long been the subject of debate, coming
to the forefront recently with publication of PVC:
Bad News Comes in Threes (the “three” referring to
the code number of the plastic resin), a joint
report by the Center for Health, Environment and
Justice and the Environmental Health Strategy Center
that characterizes PVC as “the poison plastic.”
But another draft report from the U.S. Green Build
Council’s PVC Task Group concluded that “the
available evidence does not support a conclusion
that PVC is consistently worse than alternative
materials on a life cycle environmental and health
basis.”
These reports are two voices in a dispute between
environmental advocates and the vinyl industry. The
positions have become polarized with PVC alternately
being portrayed as an environmental evil or a
panacea to the construction industry.
PVC and the Construction Industry
Construction and plastic pipes account for over
two-thirds of PVC consumption in North America and
half in Western Europe. According to PVC: Bad News
Comes in Threes, construction is also the fastest
growing PVC sector with a projected annual average
growth rate of 3.5 percent between 2002 and 2007.
According to Joan Lowy from Scripps Howard News
Service about 300 billion pounds of polyvinyl
chloride has been installed in construction and
other long-lasting uses over the last 40 years.
Determining whether a material is safe can be
difficult, especially if the material is question is
as hotly contested as polyvinyl chloride (PVC).
PVC is used in window frames and doors, gutters,
cable ducting and conduits, flooring, wall
coverings, roofing, reservoir linings, sheets and
panels, roller shutters, shower curtains, shades and
blinds, moldings and much more. The Bad News Comes
in Threes report states that gutters, fencing,
decking and other special applications account for
8.1 percent of PVC’s growth in the construction
industry, windows and doors account for 6.1 percent
and vinyl siding accounts for 4.5 percent.
PVC pipe accounts for the largest portion of all
polyvinyl chloride used in the United States. PVC is
favored in piping for its durability. “Because it’s
less prone to breaks and other failures, the cost to
repair and maintain a PVC water or sanitary system
is far less than with other materials,” says the Uni-Bell
PVC Pipe Association.
According to the Chlorine Chemistry Council, more
than 75 percent of PVC pipes will have a lifetime of
more than 40 years, with the potential for a
lifetime of 100 years with little loss of strength.
An August 2004 report Challenges and Context:
Paradoxes in Vinyl and Sustainable Design by the
Design Futures Council states “after a 6.7-magnitude
California earthquake, PVC main lines remained in
service while asbestos, cement and steel pipes
experienced hundreds of breaks.”
The Critique
Michael Belliveau — executive director of the
Environmental Health Strategy Center (a public
health organization that promotes safer alternatives
to hazardous chemicals) and co-author of PVC: Bad
News Comes in Threes — outlines several reasons why
he considers PVC to be the most environmentally
harmful plastic:
▪ PVC is toxic throughout its lifecycle; the
chemicals used to make it are cancer causing and
extremely harmful
▪ These toxic additives don’t stay in the
product, but instead come out during use especially
during disposal
▪ PVC is the only chlorine containing plastic
causing it to form dioxins, which are toxic
carcinogens.
Belliveau also feels, more than any other plastic,
PVC is full of toxic additives such as heavy metals
like lead and cadmium as well as other chemicals
that are used to soften and make the PVC flexible.
In addition to dioxin, opponents also suggest that
ethylene dichloride and vinyl chloride created in
the production of PVC can cause health problems
ranging from cancer, endocrine disruption and
endometriosis to neurological damage, birth defects
and impaired child development, and reproductive and
immune system damage.
Belliveau worries about PVC in a construction
setting because of the burning of vinyl scraps on a
rural jobsite. He also points out that the majority
of PVC is used for construction and these types of
materials tend to be “longer lived.” As a result,
opponents of PVC fear “we are building up a stock of
PVC products in use which will eventually create a
looming waste crisis. Because these products have
20-, 30-, 40-year life spans and were introduced in
the last couple of decades, they will come out of
service and there will be a huge amount of vinyl
waste full of toxic additives and chlorines that we
are ill-prepared to handle,” he says.
Opponents to PVC criticize the recent USGBC draft
saying it ignored such vital details as the use of
lead as a stabilizer in PVC production and the
association of mercury with chlorine plants.
“The chemical industry that makes this vinyl is
never going to do anything but try to market it,”
Belliveau says, suggesting numerous material
alternatives for some of the most common
construction purposes. These alternatives include
natural products as well as “cleaner” plastics such
as polyethylene and polypropylene, a list of which
are available from the Healthy Building Network on
its Web site (www.healthybuilding.net).
The Defense
Allen Blakely, a spokesman for The Vinyl Institute,
feels that the opponents of PVC are “trying to trump
up issues that really don’t seem to amount to much.”
He points to the USGBC’s draft report, calling it
“the mother of all resources.” This draft not only
concluded that PVC offers comparable environmental
and health impacts to other competing materials, but
suggested a credit in the LEED rating system for
eliminating PVC could lead those in the construction
industry to use materials that perform worse over
their lifecycles.
Blakely also states PVC pipe can meet standards set
by the National Sanitation Foundation and the
National Fire Protection Association. Furthermore,
“PVC pipe and wiring are accepted in almost every
state code in the country,” he says.
He cites a number of benefits to PVC including its
durability, versatility, energy efficiency and cost
effectiveness. Because it is durable, “you don’t
have to replace it, allowing for the conservation of
resources,” he says.
According to the Design Futures Council report, EPA
data suggests “production of vinyl has more than
tripled in the past 30 years, yet dioxin levels in
the environment have steadily declined.” It also
states “chlorine gas is not released into the
atmosphere by incineration (or recycling or
landfilling) of vinyl. A majority of the chlorine
present in incinerator waste comes from sources
other than vinyl, such as table salt and food
waste.” The Chlorine Chemical Council concludes that
restrictions on PVC would have “negative economic
consequences for the construction industry.”
Blakely maintains that PVC plastic accounts for only
1 percent of municipal solid waste. He argues that
some of the concerns of PVC opponents are outdated
and result from safety issues dating back to the
1970s. During that time, workers exposed to
prolonged, high amounts of vinyl chloride monomer
were shown to be at risk for angiosarcoma of the
liver. Improvements in the industry have resulted in
a 99 percent reduction of vinyl chloride monomer
emissions.
“Our illness and injury rate are among the lowest in
the manufacturing industry, lower than manufacturing
and the chemical industry as a whole,” he says.
“Depending on who you talk to you, you will hear a
litany of charges, but we have answers to most of
them.” |
