Heavy metals toxic effects

Other papers in the Symposium deal with the antioxidant and hypolipidemic effects of IP6, its chelating effects in heavy metal toxicity, inhibition of renal stones and other beneficial effects such as inhibition of platelet aggregation, inhibition of inflammatory responses (Shamsuddin, 1998). The lipid lowering effect and anti-neoplastic effect of 1P6 were extensively reviewed (Jariwalla, 1999). Hence, 1P6 is a valuable component of rice bran in preventing disease and maintaining health. 1P6 is present at 1.8-2% in rice bran. 

Schrauzer, G.N., Effects of selenium antagonists on cancer susceptibility New aspects of chronic heavy metal toxicity, J UOEH 9, 208, 1987. 

Heavy metals, toxic organics and other pollntants have often freqnently been added to wetlands both accidentally and on pnrpose, exploiting their buffering and storage capacities. The chemistry of snbmerged soils and sediments is such that pollutants may be effectively removed from the percolating water in redox, sorption and precipitation reactions. But the effects of long-term accumulation of pollutants on nutrient cycles and other wetland functions are not well understood. 

Baath, E. (1989). Effects of heavy metals in soil on microbial processes and populations (a review). Water, Air, and Soil Pollution, 47, 335—79-Babich, H. Stotzky, G. (1980). Environmental factors that influence the toxicity of heavy metal and gaseous pollutants to microorganisms. Critical Reviews in Microbiology, 8,99-145. Babich, H. Stotzky, G. (1985). Heavy metal toxicity to microbe-mediated ecologic... 

Ganther HE, Wagner PA, Sunde ML, et al. 1973. Protective effects of selenium against heavy metal toxicities. Proc Univ MO Annu Conf Trace Subst Environ Health. 7 247-252. 

The initial species present, their relative concentrations, the induction of their enzymes, and their ability to acclimate once exposed to a chemical are likely to vary considerably, depending upon such environmental parameters as temperature, salinity, pH, oxygen concentration (aerobic or anaerobic), redox potential, concentration and nature of various substrates and nutrients, concentration of heavy metals (toxicity), and effects (synergistic and antagonistic) of associated microflora (Howard and Banerjee, 1984). Many of the parameters affect the biodegradation of chemicals in the environment as well as in biodegradation test systems used to simulate the environment. 

Krupa Z, Baszynski T. Some aspects of heavy metals toxicity towards photosynthetic apparatus-direct and indirect effects on light and dark reactions. Acta Physiol Plant 1995 17 177-190. 

Metabonomics has already been applied in fields outside human and other mammalian systems. For example, studies in the environmental pollution field have highlighted the potential benefits of this approach by studies of caterpillar hemo-lymph [38] and earthworm biochemical changes as a result of soil pollution by model toxic substances [39]. In addition, a study of heavy metal toxicity (As + and Cd +) in wild rodents living on polluted sites has been concluded successfully [40]. In terms of monitoring water quality, one study has evaluated adverse effects in abalone using NMR-based metabonomics [41]. 

Vitamin E and selenium have roles in the immune system and protect against heavy metal toxicity. Other mutual functions and effects of deficiency in farm animals are discussed in the section on vitamin E (see pp. 81-86). 

Burd, G. T, Dixon, D. G., Ghck, B. R. Plant growth promoting that decrease heavy metal toxicity in plants. Canadian Journal of Microbiology. 2000, V. 46,247-255. Siunova, T. V., Kochetkov, V. V., Boronin, A. M. Effect of ihizosphere bacteria on nickel accumulation by barley plants. Agrochemicals. 2006, K 10,80-84. Mannanov, R. N., Saharova, R. K. Antibiotics produced by Bacillus bacteria. Chemistry of Natural Compounds. 2001, V. 37. J4 2,117-123. 

Heavy metals are of importance in human toxicity because the body possesses only inactive mechanisms for their excretion thus chronic, low level intakes can accumulate to toxic proportions. Treatment has likewise been relatively unsuccessfiil, except for symptomatic reHef. No effective means has been discovered to increase excretion. 

Sulfur Polymer Cement. SPC has been proven effective in reducing leach rates of reactive heavy metals to the extent that some wastes can be managed solely as low level waste (LLW). When SPC is combined with mercury and lead oxides (both toxic metals), it interacts chemically to form mercury sulfide, HgS, and lead sulfide, PbS, both of which are insoluble in water. A dried sulfur residue from petroleum refining that contained 600-ppm vanadium (a carcinogen) was chemically modified using dicyclopentadiene and oligomer of cyclopentadiene and used to make SC (58). This material was examined by the California Department of Health Services (Cal EPA) and the leachable level of vanadium had been reduced to 8.3 ppm, well below the soluble threshold limit concentration of 24 ppm (59). 

Environmental Concerns. Dyes, because they are intensely colored, present special problems in effluent discharge even a very small amount is noticeable. However, the effect is more aesthetically displeasing rather than ha2ardous, eg, red dyes discharged into rivers and oceans. Of more concern is the discharge of toxic heavy metals such as mercury and chromium. 

Heavy metals on or in vegetation and water have been and continue to be toxic to animals and fish. Arsenic and lead from smelters, molybdenum from steel plants, and mercury from chlorine-caustic plants are major offenders. Poisoning of aquatic life by mercury is relatively new, whereas the toxic effects of the other metals have been largely eliminated by proper control of industrial emissions. Gaseous (and particulate) fluorides have caused injury and damage to a wide variety of animals—domestic and wild—as well as to fish. Accidental effects resulting from insecticides and nerve gas have been reported. 

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