Biodegradation potential

The biodegradation process is conducted in a specially prepared medium inoculated with sludge inoculum. The process occurs under the flow of a mixture of 70% nitrogen and 30% carbon dioxide to provide anaerobic conditions. 

The boiling point of solvent, its specific heat capacity, and its enthalpy of vaporization determine the energy required for solvent separation in a distillation column. They also determine numerous other properties of solvents (see Chapter 2). 

Several methods of determination can be used, but two, distillation and gas chromatography are the most popular. Industrial aromatic hydrocarbons are determined by distillation. The temperature is recorded for the initial boiling point, for the sample which has been distilled at 5%, 10%, then at 10% increments up to 90%, then finally at 95%. The temperature should be recorded with precision of 0.1 C. A general test mediod to determine the distillation range of volatile liquids outlines a similar method of measurement In addition to the measurements at the intervals given above, the temperature of the dry point (distillation temperature of residual quantities) is also recorded. Results must be reported as specified in the method. 

A vaeuum distillation procedure is used to determine the amount of solvents in solvent-based paints. The paint sample is diluted with tricresyl phosphate, distilled for a while under normal pressure to evaporate the more volatile solvents, followed by vacuum distillation at 2 mm Hg. 

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The advantage of this test is that it is quick and easy to do, and gives an indication of biodegradation potential. However, the test is not definitive, because any impurities in the plastic, such as plasticizers and solvents, may interfere with the test by promoting growth, and thus give false positive results. 

Whyte LG, CW Greer, WE Innis (1996) Assessment of the biodegradation potential of psychrotrophic microorganisms. Can J Microbiol A2 99-106. 

Battersby NS, V Wilson (1989) Survey of the anaerobic biodegradation potential of organic chemicals in digesting sludge. Appl Environ Microbiol 55 433-439. 

Geyer R, AD Peacock, A Miltner, H-H Richnow, DC White, KL Sublette, M Kastner (2005) In situ assessment of biodegradation potential using biotraps amended with C-labeled benzene or toluene. Environ Sci Technol 39 4983-4989. 

The platform includes different decision trees for the following endpoints the estimation of Threshold of Toxicological Concern (TTC), aquatic modes of action [44], skin and eye irritation and corrosion, mutagenicity and carcinogenicity [45], in vivo micronucleus assay, identification of Michael Acceptors and biodegradation potential [46]. 

Khalid A, Arshad M, Crowley DE (2009) Biodegradation potential of pure and mixed bacterial cultures for removal of 4-nitroanaline from textile dye wastewater. Wat Res 43 1110-1116... 

Surfactants such as LAS and NPEO have been found in compartments with low oxygen content, such as anaerobic sludge digesters or anaerobic continental and marine sediments [14,15,18-25]. One of the possible causes of this persistence is the inhibition of the anaerobic digestion [17,26,27]. Battersby and Wilson [27] observed inhibitory effects of NP at 50 mg CL-1 on methane formation in a survey of the anaerobic biodegradation potential of organic chemicals in digesting... 

Moreels, D., Bastiaens, L., Ollevier, F., Merckx, R., Diels, L., and Springael, D., 2004, Evaluation of the intrinsic MTBE biodegradation potential of European contaminated subsurface soils in microcosms simulating in sim bioremediation conditions, FEME... 

Reineke W (2001) Aerobic and anaerobic biodegradation potentials of microorganisms. In Beek B(ed). The handbook of environmental chemistry, vol 2. Springer, Berlin Rivett MO, Feenstra S (2005) Dissolution of an emplaced source of DNAPL in a natural aquifer setting. Environ Sci Technol 39 447 55... 

Shelton DR, Tiedje JM. 1981. Development of test for determining anaerobic biodegradation potential. Office of Toxic Substances, U.S. Environmental Protection Agency, Washington, DC. 

Meylan, W., Boethling, R., Aronson, D., Howard, P. and Tunkel, J. (2007) Chemical structure-based predictive model for methanogenic anaerobic biodegradation potential. Environ. Toxicol. Chem., 26, 1785-1792. 

Acton, D. W. Barker, J.F. (1992). In situ biodegradation potential of aromatic hydrocarbons in anaerobic groundmatets. Journal of Contaminant Hydrology, 9,325-52. Aelion, C.M. Bradley, P. M. (1991). Aerobic biodegradation potential of subsurface microorganisms from a jet fuel-contaminated aquifer. Applied and Environmental Microbiology, 57(1), 57-63. 

Atlas, R. M. Bartha, R. (1973b). Abundance, distribution and oil biodegradation potential of microorganisms in Raritan Bay. Environmental Pollution, 4, 291-300. 

Lindstrom, J. E., Prince, R. C., Clark, J.C., Grossman, M.J., Yeager, T. R., Brown, J. F. Brown, E. J. (1991). Microbial populations and hydrocarbon biodegradation potential in fertilized shoreline sediments affected by the t/v Exxon Valdez oil spill. Applied and Environmental Microbiology, 57, 2514-22. 

Punch, W.F., L.J. Forney, A. Patton, K. Wright, P. Masscheleyn, and R.J. Larson. 1996. BESS, A computerized system for predicting the biodegradation potential of new and existing chemicals. 7th International Workshop on QSARs in Environmental Science. June 24—28, Elsinore, Denmark. 

Cook, A.M., H. Grossenbacher, and R. Hutter (1983). Isolation and cultivation of microbes with biodegradative potential. Experientia, 39 1191-1198. 

An important point is determining to what extent these results relate to actual biodegradation potential of the compounds concerned. In other words, could the regression models be considered QSBRs. This is of particular significance because a lack of reproducible quantitative data on biodegradation is one of the factors that limits the development of QSBRs (Degner et al., 1991). 

The basic test conditions favouring an assessment of the inherent biodegradation potential... 

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