lec3_green

lec3_green - B E.104 February 8, 2005 E nvironmental...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
BE.104 February 8, 2005 Environmental chemicals and Cancer clusters: Cause and effect, or coincidence? Laura Gree n page 1 Two examples (1 cause-and-effect; 1 [almost certainly] coincidence): 1.± Vinyl chloride at B.F. Goodrich plant, Louisville, Kentucky and liver cancer (angiosarcoma of the liver) 2. Trichloroethylene in East Woburn, MA, and childhood leukemia ( as in, A Civil Action )
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
BE.104 February 8, 2005 Environmental chemicals and Cancer clusters: Cause and effect, or coincidence? Laura Gree n page 2 How / why are people exposed to vinyl chloride Vinyl chloride (monomer) is polymerized to make polyvinyl chloride± (PVC) polymer. ± Commercial production began in the 1930's Worldwide production is enormous: ± currently - 18 million tons annually. RAW MATERIALS Electricity Salt 'Cracker' Electrolysis Cell Products VCM Plant Blender PVC Plant Ethylene Gas Chlorine Gas Hydrogen Gas Caustic Soda Hydrochloric Acid VCM Gas PVC Natural Gas Figure by MIT OCW.
Background image of page 2
BE.104 February 8, 2005 Environmental chemicals and Cancer clusters: Cause and effect, or coincidence? Laura Gree n page 3 Properties of vinyl chloride: Colorless gas; sweet odor . No obvious acute toxicity from early occupational exposures. Early occupational guideline for allowable exposures (pre-OSHA): 1961: American Council of Government and Industrial Hygienists (ACGIH): TLV of 500 parts per million (ppm, v/v), 8-hr. TWA. Basis? Research at Dow Chemical (Torkelson et al. , 1961 ): rodents develop liver and kidney toxicity following exposure to 500 ppm; NOAEL = 50 ppm. Recommend reduction in TLV to 50 ppm. Little action taken. Mid-1960's : Acroosteolysis appears in some Goodrich workers ( bone erosion at fingertips). Noticed by plant’s occupational physician, John Creech, M.D. (1967). Workers were screened and their hands x-rayed. Some changes made in work procedures (at least at Goodrich) to reduce exposures. Cancer case reports : 1971 : one BF Goodrich (Louisville, KY) VCM worker dies of angiosarcoma of the liver (ASL; rare form of cancer: only about 25 cases per year in U.S. expected). 1973: a second BF Goodrich worker dies of ASL, and another worker is diagnosed with ASL. Search of company death certificates: a 4 th case may have occurred in 1968. (Creech and Johnson [Goodrich’s company docs], 1974). Total workforce at this plant - 300.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
BE.104 February 8, 2005 Environmental chemicals and Cancer clusters: Cause and effect, or coincidence? Laura Gree n page 4 Case reports of Angiosarcoma of the Liver among Polyvinyl Chloride Workers B.F. Goodrich Plant, Louisville, Kentucky Dates of: Case Age at illness onset Illness onset Diagnosis Death Years worked with vinyl chloride before illness 1 43 Aug. 1967 Sept. 1967 Jan. 7, 1968 17 2 36 Jan. 1970 May 1970 Sept. 27, 1971 14 3 41 Jan. 1964 Mar. 1973 Mar. 3, 1973 14 4 58 July 1973 Dec. 1973 Dec. 19, 1973 27
Background image of page 4
BE.104± February 8, 2005± Environmental chemicals and Cancer clusters: Cause and effect, or coincidence? Laura Gree
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 11/11/2011 for the course BIO 20.010j taught by Professor Lindagriffith during the Spring '06 term at MIT.

Page1 / 24

lec3_green - B E.104 February 8, 2005 E nvironmental...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online