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After World War II, Montrose Chemical Corporation of California, 20201 S. Normandie Ave., Unincorporated LA County, California began producing Dichloro-Diphenyl-Trichloroethane (DDT), the new "wonder pesticide". Its waste disposal system funneled the plant’s processed waste into the county sewer system and ultimately into the ocean. Montrose continued producing DDT even in the face of increasing scientific concerns about DDT in the 1960s. Production did not stop until 1982.〔Kehoe, Terence and Jacobsen, Charles ("Environmental Decision Making and DDT Production at the Montrose Chemical Corporation of California" ), ''Enterprise and Society'', (2003) 4(4), pp. 640-675.〕 The site discharged an estimated 1,700 tons of DDT between the late 1950s and early 1970s alone, which contaminated ocean sediments on the floor of the Palos Verdes Shelf (PVS) near Los Angeles, California.〔(Cleaning Up the Palos Verdes Shelf | Region 9: Superfund | US EPA ) last updated July 26, 2007.〕 By designating Montrose Chemical as a Superfund site, the federal government put it on the National Priorities List as a hazardous waste site. The United States Environmental Protection Agency (EPA) was then committed to cleaning up the PVS and making the public aware of all health risks.〔(Superfund | EPA ) last updated April 30, 2008.〕 == Environmental impacts and health risks of DDT== DDT and polychlorinated biphenyls (PCBs) move from contaminated sediments into the water, so although the dumping of DDT stopped in 1983, the PVS remains contaminated 〔 DDT and PCBs enter the food chain through worms and micro-organisms living in the sediment. One fish may eat many of these organisms, causing the DDT and PCBs to accumulate in fish tissue. Fish-eating birds, marine mammals and birds of prey that feed on both, accumulate more of the toxins.〔 Since 1985, fish consumption advisories and health warnings have been posted in southern California because of elevated DDT and PCB levels. Bottom-feeding fish are particularly at risk for high contamination levels. Consumption of white croaker, which has the highest contamination levels, should be avoided. Other bottom-feeding fish, including kelp bass, rockfish, queenfish, black croaker, sheepshead, surfperches and sculpin, are also highly contaminated.〔 The effects of DDT differ depending on the organism it infects. Bald eagles on Santa Catalina Island are unable to reproduce because the DDT causes their eggshells to become too thin and to break open before the eaglet is fully developed.〔(Off Shore DDT ) last Updated 2002.〕 For people, DDT and PCBs can increase cancer risks, harm the liver and affect the central nervous system. Nursing infants whose mothers regularly consume the fish are at especially high risk.〔 As a part of the Superfund project, the EPA is looking to reinforce the commercial and recreational fishing ban on white croaker.〔(Palos Verdes Ecology ) 2002.〕 In October 1989, the former Montrose Chemical site was added to the Superfund National Priorities List (NPL). In 1990, the United States and the State of California filed lawsuits against Montrose Chemical and nine other facilities near the Palos Verdes peninsula, citing damages to the nearby marine environment. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Montrose Chemical Corporation of California」の詳細全文を読む スポンサード リンク
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