Dioxin hazardous substance

Depending on the desired application, additional refining may be necessary. For demagging (removal of magnesium from the melt), hazardous substances such as chlorine and hexachloroethane are often used, which may produce dioxins and dibenzofurans. Other, less hazardous methods, such as adding chlorine salts, are available. 

An environmental protocol has been developed to assess the significance of newly discovered hazardous substances that might enter soil, water, and the food chain. Using established laboratory procedures and C-labeled 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD), gas chromatography, and mass spectrometry, we determined mobility of TCDD by soil TLC in five soils, rate and amount of plant uptake in oats and soybeans, photodecomposition rate and nature of the products, persistence in two soils at 1,10, and 100 ppm, and metabolism rate in soils. We found that TCDD is immobile in soils, not readily taken up by plants, subject to photodecomposition, persistent in soils, and slowly degraded in soils to polar metabolites. Subsequent studies revealed that the environmental contamination by TCDD is extremely small and not detectable in biological samples. 

Similar conditions as for the formation of PCB s might also lead to the formation of small trace amounts of dioxins. A German Hazardous Substances Ordinance (Chemikalien-Verbotsverordnung) prohibits to place products on the market for which very low limits of dioxin traces are exceeded. Regulated dioxins are those which at least are tetrachloro (or bromo) substituted in 2,3,7,8-position [14],... 

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), Pentachlorophenol m(PCP, mercury and organic mercury compounds, cadmium, lead and organic lead compounds, brominated flame retardants), nonylphenol/ethoxylates (NP, NPEs) amongst others in the OSPAR Strategy with regard to Hazardous Substances... 

Incineration has been used extensively in hospitals for disposal of hospital wastes containing infectious and/or hazardous substances. Most hospital incinerators (over 80%), however, are outdated or poorly designed. Modem incineration technology, however, is available for complete destmction of organic hazardous and infectious wastes. In addition, adequate air pollution control facilities, such as scmbbers, secondary combustion chambers, stacks, and so on, are needed to prevent acid gas, dioxin, and metals from being discharged from the incinerators. 

CAS = Chemical Abstracts Services CDDs = chlorinated dibenzo-p-dioxins DOT/UN/NA/IMCO = Department of Transportation/United Nations/North America/lnternational Maritime Dangerous Goods Code EPA = Environmental Protection Agency HSDB = Hazardous Substances Data Bank NCI = National Cancer Institute NIOSH = National Institute for Occupational Safety and Health OHM/TADS = Oil and Hazardous Materials/Technical Assistance Data System RTECS = Registry of Toxic Effects of Chemical Substances... 

A large number of event sequences and consequences are possible (vid. Fig. 10.1). For example, fires and explosions may occur within the containment of materials inside the equipment or result from a release of materials. Hazardous substances may be present in the process or be generated because of deviations of process parameters from their values (e.g. larger quantities of dioxin in Seveso) or be formed in the course of an accident (e.g. combustion gases). It is evident that even in a comprehensive and detailed risk analysis it is difiicult to treat all conceivable event sequences. This is even less the case in a risk-based analysis. 

Environmental impact may mean the saving of resources, the minimization of emissions including disposal, or the avoidance of hazardous substances. The public emphasis concentrates presently on minimization of emissions if we consider the debate on global warming or on dioxins. But saving of resources will obtain equal importance in the future if the limited availability of fuel will get more public awareness again. 

The Hazards Substance Ordinance in Germany specifies the maximum level of chlorinated dibenzo-dioxins and furans that can be present in materials marketed in Germany. This has been extended to the brominated compounds. The two largest volume flame retardants decabromodiphenyl oxide and tetrabromo his-phenol A - are said to meet these requirements [1,2]. 

Toxic substances substances which generate very toxic or strongly malodorous fumes in fire water polluting substances highly malodorous subsbnces polychloro- dibenzofurans, dioxins, hydrochloric and sulfuric adds above 10% cone Separate fire compartments can be stored with low hazard substances up to total permissible level max. 250 tons per fire compartment block storage with and without pallets max. 2 rows or 8 ft deep, max. 4 layers or 16 ft high min. 4 ft between blocks... 

On the other hand, combustible wastes are utilised in the kiln as alternative thermal energy for clinker production. Since the wastes are fed into a high temperature zone in the production process, hazardous substances such as dioxins are completely decomposed in the kiln. Further, since inorganic residuals such as ash have a similar composition in terms of CaO, Si02, AI2O3 and Fc203, all components are completely integrated into the clinker product. 

Two or more oxygen atoms 2,3,7,8- tetrachlorodibenz o-p-dioxin Artemisinin Formed by burning chlorine-containing compounds with hydrocarbons, hazardous substances Anti-malarial pharmaceutical... 

Chlorinated dibenzo-p-dioxins and dibenzofurans are among the most toxic substances known, especially 2,3,7,8-tetrachloro-p-dibenzodioxin (TCDD). These extremely hazardous compounds can be produced from 3,4,5- and 2,4,5-trichlorophenols by peroxidases [207]. However, the biological formation of such toxicants in nature or by microorganisms has not been described. 

Think how many carcinogens are household names asbestos, cigarette smoke (a mixture of several thousand chemical compounds), DES, dioxin, saccharin, arsenic, PCBs, radon, EDB, Alar. Hundreds more of these substances, some very obscure, are known to the scientific and medical community, and many of these are scattered throughout the land at thousands of hazardous waste sites similar to Love Canal. People are exposed to these dreadful substances through the air they breathe, the water they drink and bathe in, and the foods they eat. Chemicals can also produce many other types of health damage, some very serious, such as birth defects and damage to our nervous and immune systems. 

Volatile organic compounds (VOC) contribute to the formation of tropospheric ozone (summer smog). Certain halogenated hydrocarbons (e.g. CFCs) also destroy the stratospheric ozone layer. Chlorinated solvents are hazardous to water and, if disposed of incorrectly (e.g. burning), may emit highly toxic substances (e.g. dioxins). 

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. 

The system for classification and disposal of hazardous chemical waste developed by EPA under RCRA does not apply to all wastes that contain hazardous chemicals. For example, wastes that contain dioxins, polychlorinated biphenyls (PCBs), or asbestos are regulated under the Toxic Substances Control Act (TSCA). In addition, the current definition of hazardous waste in 40 CFR Part 261 specifically excludes many wastes that contain hazardous chemicals from regulation under RCRA, including certain wastes produced by extraction, beneficiation, and processing of various ores and minerals or exploration, development, and use of energy resources. Thus, the waste classification system is not comprehensive, because many potentially important wastes that contain hazardous chemicals are excluded, and it is not based primarily on considerations of risks posed by wastes, because the exclusions are based on the source of the waste rather than the potential risk. 

High-hazard chemical waste could result from relatively high concentrations of hazardous organic chemicals (e.g., dioxins) or persistent toxic substances (e.g., heavy metals). Some wastes may be... 

Toxic Substances Control Act (TSCA) Law passed in 1976 that governs the regulation of toxic substances in commerce, with the objective of preventing human health and environmental problems before they occur. The manufacturing, processing, or distribution in commerce of toxic substances may be limited or banned if EPA finds, based on results of toxicity testing and exposure assessments, that there is an unreasonable risk of injury to human health or the environment. Important hazardous chemicals regulated under TSCA include, for example, dioxins, PCBs, and asbestos. 

The National Dioxin Program (2004) estimated that the dietry intake of the substances as the TEQ value and then estimated the HI against the Australian Tolerable Monthly Intake (TMI) of 70 pg TEQ kg-1 bw month-1. These values showed an increase with age with toddlers 2-4 years having HI of 0.1 to 0.5 individuals 4 to 15 years HI 0.05 to 0.35 and adults HI 0.05 to 0.25. This suggests that the dioxins are a low health hazard in the Australian environment. 

The Agency for Toxic Substances andDisease Registry (ATSDR)has adopted thispolicy guideline to assess the public health implications of dioxin and dioxin-like compounds in residential soils near or on hazardous waste sites. These compounds include... 

These substances are defined under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), as amended, commonly known as Superfund. This policy guideline will provide a clear and consistent understanding of ATSDR s current approaches andjudgments regarding hazards posed by the presence of TCDD and its less toxic dioxin-like congeners, the CDDs and CDFs, in residential soils. Likely users of this policy guideline include... 

According to the Bay Area Air Quality Management District in San Francisco, more than 5.5 million pounds of toxic chlorinated substances are released in the area annually. This includes approximately 13,000 pounds of chloroform, 1.4 million pounds of freon, 2 million pounds of perchloromethylene, and trace amounts of dioxin. (Dioxin is one of the most toxic chemicals known.) A report released in September 1994 by the U.S. Environmental Protection Agency (EPA) clearly describes dioxin as a serious public health threat. The public health impact of dioxin may rival the impact that DDT had on public health in the 1960s. According to the EPA report, not only does there appear to be no safe level of exposure to dioxin, but levels of dioxin and similar chemicals have been found in the U.S. population that are at or near levels associated with adverse health effects. The EPA report also confirmed that dioxin is a cancer hazard, exposure... 

Hazard is the inherent ability of the substance to cause an adverse effect, that is its toxicity (for example, dioxin and ricin are known, potent poisons). Exposure is the level of the substance in the air, water, or food or the dose of a drug. 

The European Union enacted the directive on the control of major-accident hazards involving dangerous substances in response to the 1976 dioxin release from the ICMESA facility near Seveso, Italy the United States enacted a similar Emergency Preparedness and Community Right-to-Know Act in response to the 1984 Bhopal disaster and 1989 Phillips Pasadena, Texas, refinery explosion and fire. 

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