Microbial degradation toxicants

Hwang H-M, RE Hodson, DL Lewis (1989) Microbial degradation kinetics of toxic organic chemicals over a wide range of concentrations in natural aquatic systems. Environ Toxicol Chem 8 65-74. 

The occurrence, behavior, and toxicity of all these emerging contaminants continue to be an intensive area of research, especially investigations about their removal from environmental waters (e.g., through advanced oxidation, photolysis, microbial degradation, etc.). Therefore, the identification of intermediates and degradation products originated as a result of these removal mechanisms is of... 

Sandhya, S. Prabu, S. K., and Sundari, R. B. T., Microbial-Degradation of Dibenzothiophene by Nocardioides. Journal of Environmental Science and Health Part a-Environmental Science and Engineering Toxic and Hazardous Substance Control, 1995. 30(9) pp. 1995-2006. 

During decomposition of plant remains, many phenolic compounds are released by leaching, microbial degradation or are synthesized by microbial activity. In forestry, problems of natural regeneration and reforestation are connected to the presence of phenolic substances deposited in the soil. Methods for extrachon and identification of toxic substances from different soil types (mineral or organic) are described. The method for extracting of soil phytotoxins is based on the use of ethylacetate and methanol (free phenolics) and alkaline hydrolysis (bound phenolics). 

Howard, P.H., Hueber, A.E., Mulesky, B.C., Crisman, J.S., Meylan, W., Crosbie, E., Gray, D.A., Sage, G.W., Howard, K.P, LaMacchia, A., Boethling, R., Troast, R. (1986) Biology, biodegradation and fate/exposure New files on microbial degradation and toxicity as well as environmental fate/exposure of chemicals. Environ. Toxicol. Chem. 5, 977-988. 

In the first year, the maximum concentrations of sulfoxide and sulfone in soil, seed potatoes, and foliage were approximately 2, 2, and 6 times, respectively, the concentrations of those metabolites measured in the second and third year treatments. These results demonstrated that enhanced microbial degradation of relatively minor insecticidal compounds in the soil can significantly affect insecticide levels in the plant (when these degradation products are the major insecticidal component accumulated). As the sulfoxide and the sulfone metabolites are the major toxicants in the foliage of potato plants grown in disulfoton-treated soil, this reduction in toxicant residues overtime can be expected to reduce insecticide efficacy. 

Steen, W.C., Paris, D.F., Baughman, G.L. (1979) Effects of sediment sorption on microbial degradation of toxic substances, in Proc. 

Steen, W.C., Paris, D.F., Baughman, G.L. (1982) Effects of sediment sorption on microbial degradation of toxic substances. In Contaminants and Sediments Fate and Transport, Case Studies, Modeling, Toxicity. Vol. 1, Baker, R.A., Editor, p. 477, Ann Arbor Science, Ann Arbor, Michigan. 

Cosolvents that organisms may use as substrates could increase the microbial degradation of the pollutant if the concentration has not reached toxic levels. 

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