A colorless, flammable, and toxic liquid when under pressure, but a gas under ordinary conditions. Polymerized vinyl chloride, called polyvinyl chloride, is a ubiquitous plastic produced in enormous quantities. While vinyl chloride has been detected at some waste sites, exposure has been much greater in the factories that produced it. However, significant efforts were exerted by industry to reduce occupational exposure. Chronic exposure resulted in "vinyl chloride disease" with liver, nerve, and circulatory damage. Epidemiological studies associated cancer of the liver (particularly angiosarcoma) and possibly the brain with occupational exposure, and thus vinyl chloride is considered to be a human carcinogen.