Smelters pollution source

The third category for interactions is high dose (III). The effects produced by this level of interaction can be seen by the casual observer. The result of high-dose exposure is destruction or severe injury of the forest system. High-dose conditions are almost always associated with point source emissions. The pollutants most often involved are SO2 and hydrogen fluoride. Historically, the most harmful sources of pollution for surrounding forest ecosystems have been smelters and aluminum reduction plants. 

Point Source a source of pollution that is well defined, such as the smokestack of a coal-fired power plant or smelter. 

Acid deposition has been known to exist since early in the industrial age. The principle pollutants responsible for the elevated levels of acidity are the oxidized forms of sulphur and nitrogen that have been emitted as by-products from non-ferrous smelters, fossil-fueled power generating stations, and motor vehicles. The pollutants are transported substantial distances from the source areas by the atmosphere. They are deposited on receptor regions remote from the sources as acidic rain, snow, and fog or as gasses and dry particulates. 

Excessive amounts of fluoride in the soil can cause tooth and bone damage in livestock. Paris of Arkansas. California. South Carolina, and Texas have soils abnormally high in fluorine content. In serious situations, diarrhea and emaciation will he exhibited by the livestock. The effects depend upon the fluorine source and species of livestock. Exceptionally high fluoride levels can he encountered near smelters where pollution safeguards have not been installed or are ineffectively maintained. As cninpared with other livestock, pigs can tolerate much more fluorine (up lo nearly 300 ppm of fluorine derived front rock phosphates). 

Contaminants in ambient air result in inhalation exposure either when the child is outdoors and breathes contaminated air or when contaminants in the air are transported indoors where the child spends time. Adverse health effects (acute and chronic) associated with inhalation of air contaminants are a common concern for people living in polluted cities, near hazardous waste sites, or close to point sources like smelters (Figure 15). Air emissions from past or current production processes, as well as volatilization of organic compounds, airborne particulates, and acid gases, may expose residents to contaminants at levels of health concern (ATSDR, 1994). In urban areas, mobile sources contribute substantially to organic, inorganic, and particulate air pollution. Fires, open burning, and wind-blown dust can also be major sources of ambient air pollution. 

U ecently, interest in sulfur utilization in asphalt paving materials has been rekindled. One of the foremost reasons for this is the potential availability of surplus sulfur recovered from secondary sources in connection with meeting environmental pollution standards (I). These sources include sulfur recovered from sour gas, from refining of petroleum, and from smelter and powerplant stack gases. Another potential saving of energy and petroleum is possible by replacing part of the asphalt binder with sulfur (2). 

Barbaris and Betterton, 1996) are also slightly above baseline concentrations, probably because of inputs from smelters, power plants, and soil dust. In most industrialized countries, sources of airborne arsenic are limited as a result of air-pollution control measures. Unless significantly contaminated, atmospheric precipitation contributes little arsenic to surface waters. 

Of the six heavy metals discussed in this chapter, Pb has been studied extensively with respect to the environmental effects. Clair Patterson, the father of environmental Pb studies, in one of his many major publications concerning the global Pb cycle (Patterson and Settle, 1987), noted that during pre-industrial times Pb in the troposphere originated from soil dusts and volcanic gases. In modern times (1950-1980) the proportion of natural Pb in the atmosphere is overwhelmed by the industrial sources of smelter emissions and automobile exhausts. Lead air pollution levels measured near our Nation s roadways decreased 97% between 1976 and 1995 due to the consequence of the Clean Air Act that eliminated leaded gasoline which interfered with the performance of catalytic converters. 

Control and reduction of ambient air pollutants in the United States has met with varying degrees of success. Unleaded gasoline now accounts for 99% of all gasoline sales. This change has virtually eliminated mobile sources as emitters of lead and reduced ambient lead levels by more than 75%. Likewise, stationary point sources of lead emissions, primarily industrial smelters, have dropped by more than 90% over the past three decades, although significant... 

Besides the natural soiuces, there are also anthropogenic sources of pollution, which are divided into two categories stationary and mobile. Some stationary sources are factories, power plants, smelters, dry cleaners and degreasing operations whereas some mobile sourees are cars, buses, planes, trucks, and trains (U.S. EPA, 2002). 

Whereas many of the before-mentioned increases in pollutant flux to a sediment are related to general growth of human and industrial activity, there are typical connections to specific local sources such discharges from smelters (Cu, Ni, Pb), metal-based industries (e.g., Zn,... 

Siberia is the vast region situated between the Ural Mountains and the Pacific Ocean. There are different large local sources of pollution inside this area such as nonferrous metal smelters, oil and gas wells, oil chemistry plants and electric power stations... 

Cadmium ranks close to lead and mercury as a metal of current toxicological concern. Cadmium is used in electroplating and galvanization, and in plastics, paint pigments (cadmium yellow), and nickel-cadmium batteries. Because <5% of the metal is recycled, environmental pollution is an important consideration. Coal and other fossil fuels contain cadmium, and their combustion releases the element into the environment. Extraction and processing of zinc and lead also lead to environmental contamination with cadmium. Workers in smelters and other metal-processing plants may be exposed to high concentrations of cadmium in the air however, for most of the population, food is the major source of cadmium. 

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