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Dioxins are probably the most studiedchemical compound in the world today, yet there is still muchabout them that is unknown. What we do know, however, is enoughto have many people calling for action.
Although frequently referred to inthe singular form, "dioxin," chlorinated dioxins areactually a group of chemicals that includes 75 dioxins, 135 furansand 209 polychlorinated biphenyls (PCBs). They are grouped togetherbecause their chemical structure is very similar, as are manyof their suspected effects. The most potent form of dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin,is often referred to as 2,3,7,8-TCDD.
Unlike many chemicals that have gainednotoriety over the past 25 years of increasing environmental awareness,dioxin is not a "product," or an intentionally producedsubstance, like DDT, Agent Orange, or Alar. Dioxin is a by-productof many industrial processes such as the incineration of garbage,medical waste or toxic chemicals; the bleaching of paper pulpwith chlorinated compounds; production of polyvinyl chloride (PVC)plastics; the manufacture of some chlorinated pesticides; secondarysmelting of copper; and other activities. In order to producedioxin, one needs organic matter (carbon), chlorine, and a chemicallyor thermally reactive environment, such as a pesticide productionfacility or an incinerator.
History of dioxin
Dioxin first gained widespread publicattention in the U.S. when it was found as a contaminant of AgentOrange, a chlorophenoxy herbicide known for its use as a defoliantin Vietnam. Military use of Agent Orange was banned in 1970. Onecomponent of Agent Orange, 2,4,5-trichlorophenol (2,4,5-T) wascancelled in the U.S. in 1987 after it was found to be contaminatedwith several forms of dioxin. 1 The use of the otherhalf of Agent Orange, 2,4-D, has been restricted but it remainsa common ingredient in many lawn care "weed and feed"preparations and is still used on some food crops, such as wheat.
Dioxin contamination also led tothe evacuation of such communities as the neighborhood in NiagaraFalls, New York which came to be known as "Love Canal,"and Times Beach, Missouri. Accidents at pesticide plants in Nitro,West Virginia in 1949, a BASF facility in Germany in 1953, andin Seveso, Italy in 1976 2 also exposed large groupsof people to high doses of dioxin.
Health effects
Dioxin has gained so much attentionbecause years of scientific research have shown it to be one ofthe most toxic substances known to humans. It has been linkedto a wide variety of health effects in people and in animals:
Recently, dioxin has gained attentionas one of more than 50 chemicals known or suspected to disturbthe hormone system of humans or animals. These chemicals are commonlyreferred to as "endocrine disrupting chemicals" or"hormone disrupters." Endocrine disrupting chemicalsare of particular concern because the health effects show up notin the exposed parent, but in their offspring. Hormones regulatemany processes in the body, including sexual development, reproductionand growth. Hormones are produced in exquisitely tiny amounts,yet exert monumental effects. Thus, scientists are concernedthat even very, very small doses of dioxin or other endocrinedisrupting chemicals could produce life-altering changes in animaloffspring and human babies.
Dioxin in the environment
Dioxin is a fat-soluble compound,so it concentrates in fat; it is not very water-soluble. It isalso difficult to break down in the body, so it tends to persistin the environment and to build up in the food chain. Thus, whenanimals at the top of the food chain (including humans) eat otheranimals or animal products, such as fish or milk, they will takein some of that animal's body burden of dioxin along with thenutrients in the food. The U.S. Environmental Protection Agency(EPA) has estimated that 90 percent of our dioxin exposure comesfrom our food. In a "typical" American diet, three-quartersof that exposure comes from beef and dairy products. 4
Most dioxin enters the food chainin two ways. The Center for the Biology of Natural Systems hasresearched dioxin emissions from combustion sources like incineratorsand cement kilns and found that dioxin can attach to dust particlesor water vapor and travel up to 1000 miles from the facility.5 The dioxin then falls to the ground, where it oftenlands on hay or grazing pastures. The dioxin particles stickto the grass or hay and thus are eaten by animals such as dairyor beef cattle. Because of its fat solubility, the dioxin concentratesin the beef fat or milk fat and is thus passed on to the humanconsumer in beef, milk or dairy products.
The other main source of contaminationcomes from wastewater discharged by pulp mills that bleach paperpulp with chlorinated compounds. Chlorine combines with organicmatter from the wood to form more than 1000 compounds referredto as "organochlorines," of which dioxin is one. Theseorganochlorines are released with wastewater into surface waterssuch as lakes or rivers, where they can build up in fish and otheraquatic wildlife. For people who rely on fish for a large portionof the protein in their diet, this can also be the major sourceof their dioxin exposure.
How to get dioxins out of theenvironment?
It is important to remember thateliminating animal fat from one's diet will not make the dioxinproblem go away; it will put farmers and fishers out of businesswhile allowing the polluting industries to keep discharging dioxininto the environment. The only way to address the dioxin problemis to phase out the processes that produce dioxin.
Alternatives are readily availablefor many of the processes that generate dioxin. Indeed, dioxinexpert Dr. Paul Connett has said, "If dioxin were a product[rather than an unwanted by-product], it would've been bannedyears ago." 6
Clean production technologies, wastereduction, reuse and recycling can eliminate the need for garbageand hazardous waste incinerators and cement kilns.
Medical waste incineration, consideredby EPA to be one of the top sources of identified airborne dioxinemissions, could be replaced with alternative technologies suchas autoclaves or microwaves. Recycling and reusable medical suppliescan greatly reduce the amount of waste needing disposal. Manyof the PVC products used in a health care setting as well as inthe home have readily available substitutes.
Nearly 60 percent of the PVC usedin the U.S. goes into construction materials, 7 andthere, too, alternatives are available for windows, siding, plumbingpipes and fittings, and other fixtures.
The pulp and paper industry can convertto processes that are "totally chlorine-free" (TCF),meaning that no chlorinated agents are used in bleaching. TheTCF process is in use at many pulp mills abroad, particularlyin the Scandinavian countries, but only one U.S. mill -- LouisianaPacific in Samoa, CA -- currently employs TCF technology. Also,many paper products do not actually require bleaching at all.
For people who want to learn moreabout dioxin and take action to prevent exposure, a number ofvaluable contacts are listed below.
Some resources for dioxin informationand action
"Stop Dioxin Exposure Campaign,"CCHW Center for Health, Environment and Justice, PO Box 6806,Falls Church, VA 22040. Phone: 703-237-2249; fax: 703-237-8389;e-mail: [email protected].
Center for the Biology of NaturalSystems, Queens College, Flushing, NY 11367. Phone: 718-670-4180;fax: 718-670-4189.
Dying from Dioxin: A Citizens'Guide to Reclaiming Our Health and Rebuilding Democracy, byLois Gibbs and the Citizens Clearinghouse for Hazardous Waste, South End Press, 1995. (ISBN 0-89608-525-2) $20.00. Availablein bookstores.
HEALTH CARE WITHOUT HARM: The Campaignfor Environmentally Responsible Health Care. Contact CharlotteBrody at CCHW or Jackie Hunt Christensen at IATP.
Institute for Agriculture and TradePolicy, 2105 1st Avenue South, Minneapolis, MN 55404. Phone: 612-870-3424;fax: 612-870-4846; e-mail: [email protected].
RACHEL'S Health & EnvironmentWeekly. Produced by the Environmental Research Foundation,PO Box 5036, Annapolis, MD 21403-7036. Phone: 410-263-1584; fax:410-263-8944; e-mail: [email protected].
Waste Not. Produced by Workon Waste USA, 82 Judson St., Canton, NY 13617. Phone: 315-379-9200;fax: 315-379-0448.
Citations:
1Basic Guide to Pesticides: Their Characteristics and Hazards,Shirley A. Briggs, Taylor & Francis: Washington, DC. 1992.p. 193
2 Dyingfrom Dioxin: A Citizens' Guide to Reclaiming Our Health and RebuildingDemocracy, by Lois Gibbsand the Citizens Clearinghouse for Hazardous Waste, South EndPress: Boston. 1995. pp. xxix - xxx.
3Ibid., pp. 138-139.
4Estimating Exposure to Dioxin-Like Compounds, Volume 1: ExecutiveSummary review draft, USEPA Office of Research and Development,USEPA: Washington, DC. June 1994. p. 36.
5"New Report Shows Dioxin Fallout Dusting Entire United States,"Environmental Media Services press release, May 18, 1995.
6Phone conversation with Dr. Paul Connett, November 29, 1995.
7Presentation by Thomas A. Waltermire of The Geon Company to Goldman,Sachs & Company Fourth Annual Chemical Investors Forum, May21, 1996.