Environmental Engineering Reference
In-Depth Information
smoke) and drafting the Asbestos Hazard Emergency Response Act (AHERA). In 1986,
President Reagan signed the Act, which also put into effect the Toxic Substances Control
Act, requiring all public and private schools to survey their structures for asbestos and
implement an “appropriate response action.”
Ironically, ridding a building of asbestos can make the air inside more hazardous than
before. When asbestos materials are torn out from walls, ceilings and between pipes,
asbestos dust contaminates the air. Had the asbestos materials not been touched in
the first place, the fibers would remain harmlessly contained in the ceiling tiles of the
insulation.
Responding to EPA and OSHA regulations, worried schools districts and homeowners
spent billions ripping asbestos products out of their buildings. In 1999, removing asbestos
materials in the United States cost about $3 billion. Throughout the 1990s, New York City
schools alone spent more than $100 million on asbestos removal, without performing an
analysis of the mineralogy of the asbestos.
Asbestos legislation continues to evolve, as does research on the suite of asbestos miner-
als. USEPA's response to asbestos has changed markedly over the years. In 1983 the agen-
cy's asbestos handbook stated that removing the material is always appropriate, while
their 1990 handbook acknowledged that asbestos removal may cause more contamination
than leaving it in place. Now, according to its Web site, “EPA's advice on asbestos is neither
to rip it all out in a panic nor to ignore the problem under a false presumption that asbestos
is risk free … asbestos material in buildings should be located [and] it should be appropri-
ately managed (Geotimes 2001).
Asbestos minerals have strong, flexible, and separable fibers that can be spun and woven.
The main commercial and industrial value of asbestos lies in its ability to be heat resistant.
For this reason asbestos was widely applied in the United Stated in manufactured goods
and building construction as a heat insulator for these products:
• Roofing, ceiling, and floor tiles
• Window caulking
• Pipe wrap and pipe insulation
• Paper products
• Friction products, such as automobile brakes, clutches, and transmissions
• Heat-resistant fabrics
• Packaging
• Gaskets
• Coatings
• Some vermiculite and talc containing products
• Fire resistant doors
Exposure to asbestos causing an adverse health effect is almost always through the inhala-
tion route. Asbestos affects the lungs and may lead to a condition called asbestosis. USEPA
classifies asbestos as a human carcinogen (Group: A1), and it has been linked to a form
of cancer called mesothelioma (USEPA 2009b). According to ATSDR (2001d), we are all
exposed to some asbestos in the air we breathe, especially in urban areas. Fortunately, the
concentrations in air are generally very low, being on the order of 0.00001-0.0001 fibers of
asbestos per milliliter of air.
Search WWH ::
Custom Search