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Vinyl Chloride
What is Vinyl Chloride?
Vinyl chloride (C.A.S. 75-01-4) is a colorless, flammable gas
with a faintly sweet odor. Its odor threshold (the level at which
most people can smell it and be warned of its presence) probably
exceeds 4,000 ppm. This is in excess of every legal standard
that has ever been applied to VCM exposure and is 4,000 times
higher than the current OSHA PEL of 1 ppm. If a person smells
VCM, that person has been grossly overexposed to the substance.
Where is Vinyl Chloride found?
Vinyl chloride monomer (VCM) is the parent compound of polyvinyl
chloride (PVC), a plastic resin used in numerous consumer
and industrial products, including containers, beverage containers,
food storage containers, wrapping film, battery cell separators,
refrigerant gas, electrical insulation, water distribution systems
such as drain pipes and hoses, flooring, windows, phonograph
records, video discs, irrigation systems, credit cards, latex
paints and
vinyl siding for homes. Vinyl chloride monomer is also used as
a copolymer in various resins used as plastic food wrap, for
example. Though most vinyl chloride monomer is used industrially
to make polyvinyl chloride products, historically vinyl chloride
monomer was used as a component of aerosol propellants for women’s
hair spray, aerosolized pesticides and some medical applications.
Although PVC is certainly a distinct product from VCM, PVC is
manufactured using VCM and PVC resins, and PVC resins all contain
some degree of VCM. Indeed, as a general rule, workers in PVC
plants sustain even higher exposure to VCM than workers engaged
in the direct manufacturer of VCM itself. Vinyl chloride-vinyl
acetate copolymers are used extensively to produce vinyl asbestos
floor tiles. Vinyl chloride also liquefies in a freezing mixture,
and polymerizes in light, air, or heat unless stabilized by inhibitors
such as phenol. Technical grade vinyl chloride is commercially
supplied as a 99.9% pure liquid under pressure, but may also
be found in EDC plants, methyl chloroform plants, and most importantly
in PVC processing and fabricating plants. Residual VCM may be
found in PVC and PVC resins that are not recognized as containing
dangerous levels of VCM.
Other names for Vinyl Chloride
Synonyms for vinyl chloride are chloroethene, chloroethylene,
chlorethylene, ethylene monochloride, monochloroethene, monochloroethylene,
VC, and vinyl chloride monomer (VCM).
What health effects may be caused by exposure
to Vinyl Chloride?
Vinyl chloride is a carcinogen, according to the Sixth Annual
Report on Carcinogens, published by the National Toxicology Program.
It is also listed as a carcinogen in EPA’s national Toxic
Release Inventory (TRI). Although evidence of the carcinogenic
effect of vinyl chloride in humans has come from groups occupationally
exposed to high doses of vinyl chloride, there is no evidence
that there is an exposure level below which no increased risk
of cancer would occur in humans. And while workers in the chemical
and plastics industries have the highest exposures to vinyl chloride
monomer, a large population of workers involved in the fabrication
of polyvinyl chloride products (children’s toys, shower
curtains, etc.) have also had exposure to vinyl chloride monomer.
Exposure to vinyl chloride has been shown to cause liver, brain,
lung cancer and lymphatic and hematopoietic malignancies (such
as lymphoma and leukemia) in multiple epidemiologic studies.
Case reports in epidemiology have shown increased incidences
of liver angiosarcomas and hemangiomas, lung angiosarcomas and
adenocarcinomas, brain angiosarcomas, other lymphomas, and lymphopoietic
system tumors in humans occupationally exposed to vinyl chloride.
Vinyl chloride may also damage the developing fetus. An excess
of spontaneous abortions has been reported among workers and
spouses of workers who had been exposed to vinyl chloride. Increased
rates of birth defects have been reported in areas where vinyl
chloride processing plants are located.
Other long-term effects of exposure to vinyl chloride include
a pseudo-scleroderma (usually manifested as a skin disease),
which causes the skin to become smooth and tight; acro-osteolysis,
which causes the bones of the fingers to erode; and Raynauds
syndrome, which damages the blood vessels in the extremities,
resulting in pain and coldness.
Immediate effects of exposure to Vinyl Chloride
If vinyl chloride is ingested, inhaled, or brought into contact
with skin, it irritates the eyes, skin, and upper respiratory
system, and causes drowsiness, dizziness, and lightheadedness.
High levels of exposure can cause headaches, stomach ulcers,
skin allergies, nausea, weakness, unconsciousness, and sometimes
death. Contact with liquid vinyl chloride can cause frostbite.
Where is Vinyl Chloride produced?
Vinyl chloride monomer is presently produced at 12 locations
in the United States:
» Westlake, Calvert City, KY
» Borden, Geismar, LA
» Condea Vista, Lake Charles, LA
» Dow, Plaquemine, LA
» PHH
Monomers, Lake Charles, LA
» Dow, Freeport, TX
» Formosa, Point Comfort, TX
» Geon, LaPorte, TX
» OxyChem, Deer Park, TX
» OxyMar, Ingleside, TX
Historically, vinyl chloride monomer and/or polyvinyl chloride
have been produced at facilities in the following US cities.
Significant vinyl chloride exposure may also occur at the tens
of thousands of PVC processing and fabrication plants scattered
across the United States, including:
» Demopolis, AL
» Long Beach, CA
» Pensacola-Pace, FL
» Calvert City, KY
» Henry, IL
» Merodosia, IL
» Louisville, KY
» Baton Rouge, LA
» Lake Charles, LA
» Plaquemine, LA
» Assonet, MA
» Leominster, MA
» New Bedford, MA
» Springfield-Indian Orchard, MA
» Midland, MI
» Flemington, NJ
» Pedricktown, NJ
» Brooklyn, NY
» Hicksville, NY
» Akron, OH
» Avon Lake, OH
» Painesville, OH
» Pottstown, PA
» Deer Park, TX
» Houston, TX
» LaPorte, TX
» Pasadena, TX
» Texas City, TX
» South Charleston, WV
» Moundsville, WV
» Carson, CA
» Delaware City, DE
» Saugus-Santa Clarita, LA
» Compton, CA
» Illiopolis, IL
» Ringwood, IL
» Owensboro, KY
» Geismar, LA
» Norco, LA
» Westlake, LA
» Fitchbury, MA
» Hebronville, MA
» South Acton, MA
» Perryville, MD
» Aberdeen, MS
» Passaic, NJ
» South Kearny, NJ
» Bainbridge, NY
» Niagara Falls, NY
» Ashtabula, OH
» Huron, OH
» Oklahoma City, OK
» Cranston, RI
» Freeport, TX
» Ingleside, TX
» Oyster Creek, TX
» Point Comfort, TX
» Institute, WV
» Point Pleasant, WV
» Guayanilla,
Puerto Rico
How is the production of Vinyl Chloride
regulated?
As of 1974, the consumer Product Safety Commission, EPA and
the FDA have all banned the use of vinyl chloride as an aerosol
propellant. The Clean Air Act addresses vinyl chloride emissions
from production and manufacturing facilities.
Under the Clean Water Act, EPA published a water quality criteria
document addressing vinyl chloride for the protection of human
health. EPA also regulates vinyl chloride as a hazardous constituent
of waste under the Resource Conservation and Recovery Act. Under
the Safe Drinking Water Act, EPA established a maximum contaminant
level for vinyl chloride.
The FDA eliminated the use of vinyl chloride in drug products
and proposed alerting food manufacturers to the need for monitoring
packaging materials that may contain it.
OSHA has established permissible exposure limits for vinyl chloride,
and regulates vinyl chloride under the Hazard Communication Standard
and as a chemical hazard in laboratories.
Under the Emergency Planning and Community Right-to-Know Act
of 1986, releases of more than 1 pound of vinyl chloride into
the air, water, and land must be reported annually and entered
into the national TRI. The three states in which the largest
amounts of vinyl chloride were released in 1989 were Texas (236,685
pounds), Louisiana (175,040 pounds) and Delaware (174,637 pounds).
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