Environmental effects smelters

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. 

R.C. Brewer, J.B. Brodie, L.D. Kornder et al, Environmental Effects of Emissions from the Alcan Smelter at Kitimat, B.C. Ministry of Environment, Province of British Columbia, 1979. 

Miners health had been a concern of the federal government for all of seven years, since the creation of the Bureau of Mines. The two doctors were on loan to that agency, among whose purposes it was to ameliorate the health and environmental effects of mining.1 The Bureau was now relocating its medical research to the city that already housed the smelter smoke investigation. 

Klumpp, A., Hintemann, T., Santana Lima, J. and Kandeler, E. (2003) Bioindication of air pollution effects near a copper smelter in Brazil using mango trees and soil microbiological properties. Environmental Pollution, 126(3), 313-21. 

Certain adverse environmental conditions reduce the injurious effects of air pollutants on plants. This knowledge permits us to understand why plants in some parts of the country are more seriously affected by a given pollution level than others. This fact becomes more obvious when one notes the destructive impact of sulfur dioxide from smelters in Ducktown, Tenn., and the slight effect of smelters with similar emissions in the Southwest. Two factors interplay here—the type of vegetation and the arid environmental conditions. The Southwest has native plants which have adapted to arid conditions. These adaptive features... 

In the end, the only significant control measures were smoke-collecting devices—settling chambers, baghouses, and electrostatic precipitators—that captured arsenic but had little effect on sulfur emissions. Arsenic could be sold market demand grew rapidly between 1918 and 1923 after it was shown that calcium arsenate could control the boll weevils that devastated cotton crops. In 1923, Anaconda added more precipitators soon the smelter by itself produced nearly enough arsenic to saturate the pesticide market nationwide, and the company worked intensely to find additional uses. Spread across farm fields and sprayed on fruit, the arsenic captured in the precipitators created a new set of environmental problems that would be bequeathed to posterity.13... 

MacMillan Smoke Wars, pp. 243—245 Quivik, Smoke and Tailings, pp. 434— 438. The Anaconda smelter produced 14,000 tons of arsenic in 1933 (it is unclear whether this is expressed as As or as As203) T. LeCain, The Limits of Eco-efficiency Arsenic Pollution and the Cottrell Electrical Precipitator in the U.S. Copper Smelting Industry, Environmental History, vol. 5, pp. 336—351 (2000). Arsenic usage for pesticides in the United States in 1934 can be calculated from P. A. Neal et al., A Study of the Effect of Lead Arsenate Exposure on Orchardists and Consumers of Sprayed Fruit, Public Health Service Bulletin 267, 1941, p. 12, as approximately 21,000 tons (as As). In this calculation, the average arsenic content of lead arsenate is assumed to be 20% and the annual consumption of Paris green is assumed to be 4.5 million pounds. 

Lagerwerff, J.V., Brower, D.L., 1974. Effect of a smelter on the agricultural conditions in the surrounding environment. In Hemphill, D.D. (Ed.), Trace Substances in Environmental Health. No.8. University of Missouri, Colombia, pp. 203-212. 

Baker DE, Bowers ME. 1988. Health effects of cadmium predicted from growth and composition of lettuce grown in gardens contaminated by emissions from zinc smelters. Preprint of paper presented at the 22" Annual Conference on Trace Substances in Environmental Health, St. Louis, MO, May 23-26. University Park, PA The Pennsylvania State University Department of Agronomy, Paper No. 7908, 1-15. 

Pb s inhibition of a Zn-requiring enzyme such as 6-ALA-D raises several questions about this ternary interaction with respect to environmental and occupational exposures to both metals versus enzyme effects and potential consequences for an adverse Pb effect on the heme biosynthesis pathway in groups with Zn deficiencies. Zn, as an essential trace nutrient, is under homeostatic control in terms of its biokinetics and metabolic disposition (Zinc. WHO, 1996). Consequently, one expects that bioavailability of Zn to zinc-metaUoenzymes is regulated, unlike Pb, and has limited access to the enzyme active site in various species and various organs and tissues within species. Early studies (Meredith and Moore, 1980) have shown that a range of serum Zn levels have httle impact on Pb-induced inhibition. One consequence is that smelter workers exposed to elevated levels of both Pb and Zn in Pb—Zn operations would probably not be expected to have elevated Zn exposures offsetting Pb inhibition of 6-ALA-D and overall heme biosynthesis. Roth and Kirchgessner (1981) in their studies of experimentally produced Zn deficiency showed lowered enzyme activity. However, Zn deficiency in human populations is relatively rare (Zinc. WHO, 1996). 

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