Environmental arsenic pollution

The foregoing shows that arsenite in aerobic environments can undergo bacterial oxidation to arsenate. Since, as shown in the chapter on arsenate reduction, some anaerobic bacteria have the ability to reduce As(V) to different lower oxidation states, bacterial arsenite oxidation must represent part of a microbial arsenic cycle. Microbial activity can also mobilize arsenic in some minerals as arsenite and/ or arsenate. These microbial activities have to be considered in any assessment of environmental arsenic pollution. 

Severe local arsenic pollution can occur adjacent to industrial enterprises producing the various arsenicals used in timber preservation and as agricultural pesticides. Concern expressed by environmental groups has led to a reduction in the use of arsenicals in agriculture over the last decade, and this trend is likely to continue. Waste disposal is the main problem in industrial arsenic production and this problem has been responsible for closing several plants in Western Europe. 

Diamond, M.L. (1995) Application of a mass balance model to assess in-place arsenic pollution. Environmental Science... 

Garelick, Hemda, Huw Jones, Agnieszka Dybowska, and Eugenia Valsami Jones. Arsenic Pollution Sources. Reviews of Environmental Contamination and Toxicology 197 (2008) 17 60. 

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. 

Staveland, G., I. Marthinsen, G. Norheim, and K. Julshamn. 1993. Levels of environmental pollutants in flounder (Platichthys flesus L.) and cod (Gadus morhua L.) caught in the waterway of Glomma, Norway. II. Mercury and arsenic. Arch. Environ. Contam. Toxicol. 24 187-193. 

But if we take into account the emerging pollutants and compounds, the choice of which is guided by environmental considerations (mainly risks for health), then surfactants, endocrine disruptors, pesticides, other industrial organics (PAH, aromatic amines,...) or inorganics (sulphides, arsenic,...) and microbiological indicators (pathogens) must also be considered. 

Similarly, legislation has been, or will be, introduced to deal with the disposal of treated wood waste at the end of a product lifetime. No longer will it be acceptable to dispose of treated wood waste by dumping in landfill. Proper disposal will require the incineration of treated wood waste in appropriate facilities that have the necessary equipment to prevent stack emissions of toxic compounds. This requires expensive investment to build plant that can meet the relevant environmental requirements. Such methods probably represent the best option for the permanent removal of these potential pollutants. The ash generated in these plants may contain high concentrations of arsenic, which will then have to be disposed of as hazardous waste. 

National Academy of Sciences (1977). Medical and Biological Ejfects of Environmental Pollutants Arsenic. Washington, D.C., 117-172. 

NRC. Arsenic Committee on Medical and Biological Effects of Environmental Pollutants, National Research Council, National Academy of Sciences Washington, DC, 1977 ISBN 0-709-02604-0. Wirth, N. Hazardous chemical safety. Operations Forum, Water Environment Federation, Alexandria, VA, 1998, 10 (8). 

Forrester Environmental Services, Inc., has developed a group of technologies for the stabilization of wastes containing heavy metals, such as lead, cadmium, arsenic, mercury, copper, zinc, and antimony. These technologies have been used in both industrial pollution prevention and remediation applications. One version of the technology involves the use of water-soluble phosphates and various complexing agents to produce a less soluble lead waste. This process results in a leach-resistant lead product. 

Although these cations and anions are indispensable, excessive amounts of them are toxic, so that it is important that their concentrations are regulated, either by mechanisms existing in the animal or by externally imposed controls. There are also several kinds of metal ions found in Nature which do not appear to serve any useful biological function but which are highly toxic if they are absorbed into the body. These include arsenic and the environmental pollutants lead, cadmium and mercury ions. Most of the remaining metals occur as inert species such as the aluminosilicates and titanium dioxide that are poorly absorbed, if at all, by plants and animals, or are present in only trace amounts and have little physiological effect. 

Hingston, J.A., Collins, C.D., Murphy, R.J. and Lester, J.N. (2001) Leaching of chromated copper arsenate wood preservatives a review. Environmental Pollution, 111, 53-66. 

Armienta, M.A., Villasenor, G., Rodriguez, R. et al. (2001) The role of arsenic-bearing rocks in groundwater pollution at Zimapdn valley, Mexico. Environmental Geology, 40(4-5), 571-81. 

Cooper, C.M. and Gillespie, W.B. Jr. (2001) Arsenic and mercury concentrations in major landscape components of an intensively cultivated watershed. Environmental Pollution, 111, 67-74. 

Doyle, M.O. and Otte, M.L. (1997) Organism-induced accumulation of iron, zinc and arsenic in wetland soils. Environmental Pollution, 96(1), 1-11. 

Kim, M.-J., Nriagu, J. and Haack, S. (2002) Arsenic species and chemistry in groundwater of southeast Michigan. Environmental Pollution, 120(2), 379-90. 

Van Herreweghe, S., Swennen, R., Vandecasteele, C. and Cappuyns, V. (2003) Solid phase speciation of arsenic by sequential extraction in standard reference materials and industrially contaminated soil samples. Environmental Pollution, 122(3), 323-42. 

Committee on Medical and Biologic Effects of Environmental Pollutants (1997) Arsenic, National Academy of Sciences, Washington, DC. 

Helsen, L. and Van Den Bulck, E. (2005) Review of disposal technologies for chromated copper arsenate (CCA) treated wood waste, with detailed analyses of thermochemical conversion processes. Environmental Pollution, 134(2), 301-14. 

Farooqi, A., Masuda, H. and Firdous, N. (2007) Toxic fluoride and arsenic contaminated groundwater in the Lahore and Kasur districts, Punjab, Pakistan and possible contaminant sources. Environmental Pollution, 145(3), 839-49. 

Milintawisamai, M., Boonchaleamkit, S., Fukuda, M. and TabucAnon, M.S. (1998) Application of isotope techniques to the study of groundwater pollution by arsenic in Nakorn Si Thammarat Province, Thailand, Isotope Techniques in the Study of Environmental Change Proceedings Series, International Atomic Energy Agency, pp. 473-481. 

The presence of elements known to have adverse health effects in humans such as lead and arsenic is obviously undesirable in food. Environmental sources are the main contributors to contamination of food with most metals and other elements. Some elements (e.g. arsenic) are present naturally but the major sources of other elements (e.g. lead) in the environment are from pollution from industrial and other human activities. The presence of metals and other elements in food can also be the result of contamination from certain agricultural practices (e.g. cadmium from phosphate fertilisers) or manufacturing processes (e.g. tin in canned foods). 

Of the elements in the Periodic Table more than two thirds are metals. Although many of these metals are toxic, only some metals are major environmental pollutants, because of their widespread use. U S. EPA has classified 13 metals as priority pollutants aluminum, antimony, arsenic, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and zinc. The Resource Conservation and Recovery Act has fisted eight metals whose mobility in the soil is measured to determine the characteristic of toxic wastes. These metals include arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver—all but one from the above list of priority pollutant metals. 

Another very important role that metal oxides such as Mn(III/IV) play in soils and sediments is the oxidation of inorganic cations. These reactions can be both advantageous and deleterious to environmental quality. On the positive side, oxidation of toxic arsenite [As(III)] to arsenate [As(V)] ny Mn(III/IV) oxides has been demonstrated (Oscarson et al., 1980). On the negative side, Mn(III/IV) oxides can effect oxidation of Cr(III) and Pu(III) to Cr(VI) and Pu(VI). These latter forms are very mobile in soils consequently, they can be toxic pollutants in the underlying aquatic environment (Amacher and Baker, 1982). 

---