Microbial pollution

Keywords. Organic pollutants, Microbial transformations, Biodegradation, Bioremediation, Microorganisms, Aqueous-solid phase systems, Contaminated Sediments... 

Fig. 6 DGGE profiles of PCR-amplified 16S rRNA fragments, using universal bacterial primers, obtained from the heavily polluted microbial mats of Wadi Gaza (WG) and mats collected at the end of a petroleum compounds-biodegradation experiment. The DGGE shows the enrichment of certain populations (marked by arrows) which are not detected in the controls. Sequencing of these bands showed that they belonged to the Holophaga/Geothrix/Acidobacterium phylum and chloroflexus group [60]...

Duarte GF, Rosado AS, Seldin L, Araujo WD, Elsas JDV (2001) Analysis of bacterial community structure in sulfurous-oil-containing soils and detection of species carrying dibenzothiophene desulfurization. Appl Environ Microbiol 67 1052-1062 Abed RMM, Safi NMD, Koster J, Beer D, El-Nahhal Y, Rullkotter J, Garcia-Pichel F (2002) Microbial diversity of a heavily polluted microbial mat and its community changes following degradation of petroleum compounds. Appl Environ Microbiol 68 1674-1683... 

As indicated above, national policies and international conventions have been invoked to curb known, and usually obvious, sources of marine pollution. National legislation is used to control coastal discharges of contaminants. A major problem remains owing to the inadequate treatment of sewage prior to emission from land-based sources. The most important deleterious effects in this case are with respect to microbial water quality. This can have a direct influence on bathing criteria and result in beach closures during contamination episodes. An additional problem from land-based sources pertains to transboundary effects, whereby pollution may inadvertently be exported from one country to another. 

Soil reaction (pH) The relationship between the environment and development of acid or alkaline conditions in soil has been discussed with respect to formation of soils from the parent rock materials. Soil acidity comes in part by the formation of carbonic acid from carbon dioxide of biological origin and water. Other acidic development may come from acid residues of weathering, shifts in mineral types, loss of alkaline or basic earth elements by leaching, formation of organic or inorganic acids by microbial activity, plant root secretions, and man-made pollution of the soil, especially by industrial wastes. 

Megharaj M, Singleton I, McClure NC. 1998. Effect of pentachlorophenol pollution towards microalgae and microbial activities in soil from a former timber processing facility. Bull Environ Contam Toxicol 61 108-115. 

Sanchez MA, M Vasquez, B Gonzalez (2004) A previously unexposed forest soil microbial community degrades high levels of the pollutant 2,4,6-trichlorophenol. Appl Environ Microbiol 70 7567-7570. 

Munnecke DM, LM Johnson, HW Talbot, S Barik (1982) Microbial metabolism and enzymology of selected pesticides. In Biodegradation and Detoxification of Environmental Pollutants (Ed AM Chrakrabarty), pp. 1-32. CRC Press, Boca Raton, FL. 

A further application of the manipulation of microbial activity in the rhizo-sphere is their potential to remediate contaminated land. Bioremediation involves the u.se of microorganisms that break down contaminants. Radwan et al. (255) found that the soil associated with the roots of plants grown in soil heavily contaminated with oil in Kuwait was free of oil residues, presumably as a result of the ability of the resident rhizosphere microflora to degrade hydrocarbons. The use of plants as a means to accumulate pollutants such as heavy metals (256,257) to degrade hydrocarbons and pesticides (255) is already widely implemented and has proven to be successful. In some cases, there is no doubt that it is the plant itself that is responsible for the removal of the contaminants. However, in most... 

Regardless of whether the microbes are native or artificially introduced into the soil, it is important to understand the mechanisms by which they degrade or detoxify hazardous pollutants through their metabolic activity. Understanding these mechanisms is essential for the proper design of bioremediation systems that provide the optimum conditions and the required nutritional supplements for the specific microbial process. 

Alexander M. 1974. Microbial formation of environmental pollutants. Adv Appl Microbiol 18 1-73. 

Still, the rate of transformation of organic pollutants must depend on the structure of the compound and the metabolic capacity of microbial communities. The simplest expression of this duality is the second-order equation ... 

Harvard School of Public Health, Evaluating the interrelationships between Boston, MA the microbial and metal pollutants in the... 

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