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Porphyria Educational Services


PORPHYRIA EDUCATIONAL SERVICES
Bulletin Vol. 1 No. 27 July 4, 1999
Focus: Polyvinyl Chloride, Phalates & Vinyl Chloride

What is Polyvinyl Chloride or Phthalate?

Polyvinyl Chloride (PVC, or Vinyl) aka Phthalates are one of the most commonly used materials in the consumer marketplace. Polyvinyl Chloride is found in packaging, construction and automotive material, all categories of products, including toys, and medical equipment.

PVC contains Phthalates, which accumulate in body tissues, and can damage liver, lungs, and have been shown in lower mammals to damage reproductive organs.
Phthalates are freely given off by plastics in which it occurs, and because it is fat soluble, is found in quantity in meats and cheeses wrapped in PVC packaging. Although Phthalates show almost no toxicity in adult humans in acute (short term) doses, even at high doses, it is the cumulative nature of phthalate toxicity which results in toxic effects even at very low dosage when ingested chronically (over a long period of time). Very young infants do not metabolize Phthalates as well as adults, and so are at greater risk of harm. The common availability of Phthalates in the consumer environment causes inevitable chronic ingestion for almost all modern industrial consumers.

However there is another side to PVC's. When lives are on the line, healthcare providers around the country trust vinyl medical products. For more than 40 years, vinyl medical products have played a crucial role in hospitals, clinics and other health care settings. From blood and IV bags to dialysis tubing, catheters and inhalation masks, vinyl's unique characteristics meet the health care industry's tough performance standards while also being durable, easily sterilized and non-breakable. Indeed, no other material on the market performs as well or as cost effectively as vinyl.

VINYL CHLORIDE There is sufficient evidence for the carcinogenicity of vinyl chloride. >1979; IARC S.4, When administered by inhalation, vinyl chloride induced pulmonary adenomas and adenocarcinomas, mammary adenocarcinomas, liver angiosarcomas, and angiosarcomas and adenocarcinomas.
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Inhalation of vinyl chloride induced Zymbal gland carcinomas, nephroblastomas, and liver angiosarcomas in rats of both sexes and mammary tumors and heptacellular carcinomas in female rats. Also when administered by inhalation, vinyl chloride induced skin tumors in male hamsters.

An investigative reports shows that there is sufficient evidence for the carcinogenicity of vinyl chloride in humans Vinyl chloride has been associated with tumors of the liver, brain, lung, and hematolymphopoietic system. A large number of epidemiological studies and case reports have substantiated the causal association between vinyl chloride and angiosarcoma of the liver. Several studies also confirm that exposure to vinyl chloride causes hepatocellular carcinoma, brain tumors, lung tumors, and malignancies of the lymphatic and hematopoietic system.

Vinyl chloride is a colorless, flammable gas with a faintly sweet odor. The gas polymerizes in light and liquifies in a freezing mixture. It is slightly soluble in water, soluble in ethanol, and very soluble in ether, carbon tetrachloride, and benzene.

In the form of vapor, vinyl chloride is a dangerous fire and severe explosion hazard when exposed to heat, flame, or oxidizers. On standing, it forms peroxides in air and can then explode.

Vinyl chloride is industrially important because of the inherent flame retardant properties of its polymer, its wide variety of end use products, and the low cost of producing polymers from it Vinyl chloride monomer is the parent compound of polyvinyl chloride (PVC), a plastic resin used in innumerable consumer and industrial products, including containers, wrapping film, battery cell separators, electrical insulation, water distribution systems (water and drain pipes, hose), flooring, windows, phonograph records, videodiscs, irrigation systems, and credit cards. Vinyl chloride-vinyl acetate copolymers are used extensively to produce vinyl-asbestos floor tiles/ The primary routes of potential human exposure to vinyl chloride are inhalation and dermal contact. Potential human exposure to vinyl chloride occurs in the workplace, through general air and water pollution, and to a limited extent, from the use of fabricated products Never use such products for cooking food in a microwave.

Hexachlorobenzene Hexachlorobenzene is a white crystalline solid. This compound does not occur naturally. Hexachlorobenzene was widely used as a pesticide until 1965. It was also used to make fireworks, ammunition, and synthetic rubber.

It is formed as a by-product during the manufacture of chemicals use for making solvents, other chlorine-containing compounds, and pesticides. Small amounts of hexachlorobenzene can also be produced during combustion processes such as burning of city wastes. It may also be produced as a by-product in waste streams of chlor-alkali and wood preserving plants.

There are no current commercial uses of the substance.

Hexachlorobenzene tends to remain as a solid in the environment for a long Most of it will be in the form of particles clinging to the bottom and sides of lakes or streams, since it does not dissolve in water very well. The evaporation of this substance into the air is not significant under ordinary conditions