Dioxin contamination

In cleaning up the site, dioxin-contaminated waste from the reaction ve.ssel were pac ked i ri turty-oric barrels that went astray in May 1983. They were eventually found in 1985 in the luirdicrn french town of Anguilcourt-le-Sart at an abattoir. Their contents were burned in t d i liigh-temperature incinerator. 

In any industrial facility, from offices to factories and laboratories, spills happen and create a variety of risks to workers. Inside a plant, spills result in chemicals on the floor, in the air, or on the workers themselves. When releases occur outside the plant (e.g., chemical releases from tank cars or trucks, the spread of noxious fumes from an internal spill), the potential for harm extends far beyond the facility, particularly with major catastrophes such as the Bhopal chemical release, the Exxon Valdez oil spill. New York s Love Canal, and dioxin-contaminated Times Beach in Missouri, have led several federal departments and agencies to enact protective regulations. These protections are aimed at protecting a much broader range of people, property, and the environment than most regulations administered by OSHA. 

J. Wu, A quantitative Method for Evaluating the Potential of Chemicals for Dioxin Contamination, Richover Science Institute, (1985). 

Phenoxyacids (PA) have been widely used as herbicides in agriculture, forestry, and, to a lesser extent, garden activities. The principal products are represented by 2,4-D (2,4-dichlorophenoxyacetic acid) 2,4,5-T (2,4,5-trichlo-rophenoxyacetic acid) and MCPA (4-chloro, 2-methylphenoxyacetic acid) (Stevens and Sumner, 1991). 2,4,5-T has been banned in many countries for a long time because of contamination of the commercial formulations of 2,4,5-T by 2,3,7,8-tetrachlorodibenzodioxin. At present, dioxin contamination of these formulations has been reduced to very low concentrations. 

More recently, a range of other quality and safety issues have been recognised by consumers and now influence poultry meat and egg buying patterns and behaviour. Most importantly this includes (i) the routine use of antibiotics as growth promoters and curative medicines and the potential for development of transferable antibiotic resistance, (ii) risk associated with enteric pathogen (e.g. Salmonella and Campylobacter) and toxin (e.g. dioxin) contaminants of poultry products, (iii) the environmental impact of poultry production and (iv) the sensory and nutritional quality of eggs and poultry meat (Menzi et al., 1997 Hamm et al., 2002 Rodenburg et al., 2004 Horsted et al., 2005). 

Hart, L.E., K.M. Cheng, P.E. Whitehead, R.M. Shah, R.J. Lewis, S.R. Ruschkowski, R.W. Blair, D.C. Bennett, S.M. Bandiera, R.J. Norstrom, and G.D. Bellward. 1991. Dioxin contamination and growth and development in great blue heron embryos. Jour. Toxicol. Environ. Health 32 331-344. 

Terrence Collins is the Thomas Lord Professor of Chemistry at Carnegie Mellon University who contends that the dangers of chlorine chemistry are not adequately addressed by either academe or industry, and alternatives to chlorine and chlorine processors must be pursued. He notes, Many serious pollution episodes are attributable to chlorine products and processes. This information also belongs in chemistry courses to help avoid related mistakes. Examples include dioxin-contaminated 2,4,5-T, extensively used as a peacetime herbicide and as a component of the Vietnam War s agent orange chlorofluorocarbons (CFCs) polychlorinated biphenyls (PCBs the pesticides aldrin, chlordane, dieldrin, DDT, endrin, heptachlor, hexachlorobenzene, lindane, mirex, and toxaphene pentachlorophe-... 

To determine the soil persistence of the two phenoxy herbicides contained In Herbicide Orange and the dioxin contaminant. 

Dioxin-contaminated sites, which pose a human health threat, have been the subject of recent analyses by the Centers for Disease Control (CDC) in Atlanta, GA. It has been determined by CDC that 1 ppb of dioxin is detrimental to public health and that people should be dissociated from the hazard. A level of 1 ppb of dioxin (2,3,7,8-TCDD) in soil is recommended as an action level. In cases where soil concentrations exceed 1 ppb, it is recommended by CDC that potential human exposure to the contamination be examined further. If there is human exposure to I ppb or higher on a regular basis, cleanup is indicated. A substance that may be more toxic and hazardous than dioxin is expected to be discovered in the near future. 

Chronic exposure is associated with an increased prevalence of conjunctivitis, chronic sinusitis, bronchitis, polyneuritis, and dermatitis. Chloracne has been reported and is probably the result of dioxin contaminants in commercial-grade pentachlorophenol. On the skin, solutions of pentachlorophenol as dilute as 1 % may cause irritation if contact is repeated or prolonged. 

Most, if not all, occupational illnesses associated with 2,4,5-T (such as chloracne) have been found to be the result of product contamination with TCDD. TCDD is extremely toxic to animals, and exposure has also been associated with liver function impairment, peripheral neuropathy, personality changes, porphyria cutanea, hypertrichosis, and hyperpigmentation in humans. TCDD is a chlorinated dioxin, one of a large number of related compounds referred to as dioxins it has no functional use and is not intentionally produced. It has been identified as the responsible toxic agent in several industrial disasters, such as accidental releases at Nitro, WV in 1949, and at Seveso, Italy in 1976. " The role of dioxin contaminants must also be considered in the discussion of 2,4,5-T toxicology. 

The process is best suited to treat soil contaminated with hydrocarbons and metals but has also been used to treat dioxin-contaminated soil. This treatment process can also be adjusted to account for soils with excessive moisture. 

The APEG-PLUS process is a technology for the ex situ treatment of chlorinated contaminants in a number of media. It is a form of alkaline dechlorination that uses an alkaline metal hydroxide with polyethylene glycol (APEG) as a reagent. It has been used to treat dioxin-contaminated... 

One of the most striking consumer trends in recent years has been the increasing demand for natural and healthy foods where ethical issues (such as animal welfare and health) are also taken into consideration (Andersen et al., 2005). Safety has also become a very important issue of concern in modern food production, prompted mainly by several health crises (hormones, bovine spongiform encephalopathy (BSE), antibiotics, dioxin contamination of feed, etc.). 

The teratogenic potential of chlorophenoxyacetic acid derivatives cannot be unambiguously evaluated without consideration of the dioxin contaminants formed from the monomers by a 2-step condensation at elevated temperatures ... 

There have been accidental releases of pollutants that have cause effects on humans and wildlife, such as Yucheng in Taiwan, Yusho in Japan (Ikeda, 1996), PCB contamination of poultry in Belgium (Bernard et al., 1999), Seveso in Italy (Mocarelli, 2001), and dioxin contamination by redistribution and burial of contaminated soils at Love Canal in the USA (Vianna, 1983). However, despite intensive and rapid industrialization and urbanization, such massive POPs related cases have not occurred in South Korea. Since the 1990s, monitoring South Korea has rarely found POP concentrations as great as parts per million (ppm). 

Schecter, A., Dai, L.C., Papke, O., Prange, J., Constable, J.D., Matsuda, M., Thao, V.D., Piskac, A.L., 2001. Recent dioxin contamination from Agent Orange in residents from a southern Vietnam city. J. Occup. Environ. Med. 43, 435 143. 

Dioxin contamination in open dumping sites in Asian developing countries... 

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