Fate analysis, biodegradation

The fate analysis of the biodegradation of water soluble polymers has long been a concern of the detergent industry [64], The biodegradation of such compounds in an aerobic environment is assessed by a carbon balance of the process using the following equation [65] ... 

Lourenfo ND, Novais JM, Pinheiro HM (2003) Analysis of secondary metabolite fate during anaerobic-aerobic azo dye biodegradation in a sequential batch reactor. Environ Technol 24 (6) 679-686... 

There are also several methods to determine patterns of fate and transport of pollutants in the environment. In some cases, microcosms and me-socosms are used to study fate, biodegradability, bioavailability, and transport within compartments. Field surveys may also be used to study fate and transport of pollutants in contaminated environments. Such studies involve collection and analysis of biota, water, air, soil, or sediment. In some cases, radioactively labeled contaminants ( tracers ) may be introduced in mesocosms or noncontaminated environments in order to determine their fate and patterns of transport. Finally, mathematical models are often used to produce computer simulations to... 

If Cr > 0, the fate of the incompletely biodegraded residue is important, especially the toxicity of the residue. For an anaerobic process, the equivalent analysis would be described by the following equation ... 

Biodegradation prediction is important for many reasons, some of which have already been mentioned to fill the gap between known chemical compounds and known metabolism to help design environmentally safe molecules to steer the chemical analysis in degradation route studies and to know more about the fate of chemicals in the environment. 

The metabolic fate of RDX was studied in a mixed culture incubated under methanogenic conditions. Analysis by HPLC confirmed the loss of RDX and the formation of mono-, di-, and trinitroso-RDX as transient biodegradation intermediates. An additional peak observed in the HPLC chromatogram was identified by LC-MS as hydroxylamino-dinitroso-l,3,5-triazine <2001ETC1874>. 

To proceed with this analysis, we have made independent measurements of the biological degradation rate in soil-free systems and coupled this wifii the abiotic mass transfer rates found from the desorption studies. In other words, in an effort to understand the total system, we have separated two of the key factors in the ultimate fate of a contaminant, desorption and biodegradation, and measured each in the absence of the other. The biodegradation rate can be extracted from the intrinsic biokinetic parameters for the active degraders. In our case, we will employ the Michaelis-Menten parameters measured in soil-free systems for the inoculated culture CRE7. For an initial cell concentration of 1.94 X 10 CFU/mL, the biokinetic parameters for CRE7 were as follows r 7.10 X 10 pg/L/day Km=SS3 pg/L. These parameters were coupled widi both the labile and resistant desorption constants fit to the desorption profiles to calculate a bioavailabilty number which is summarized in Table 3. 

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