Benzol a Ipyrene

Lu, P.Y., Metcalf, R.L., Plummmer, N., Mandel, D. (1977) The environmental fate of three carcinogens benzol a Ipyrene, benzidine, and vinyl chloride evaluated in laboratory model ecosystems. Arch. Environ. Contam. Toxicol. 6, 129-142. 

Heinrich, U., M. Roller, and F. Pott, Estimation of a Lifetime Unit Lung Cancer Risk for Benzol a Ipyrene Based on Tumour Rates in Rats Exposed to Coal Tar/Pitch Condensation Aerosol, Toxicol. Lett., 72, 155-161 (1994). 

There are many tricks and shortcuts to this process. For example, rather than compiling all of the transformation rate equations (or conducting the actual kinetic experiments yourself), there are many sources of typical chemical half-lives based on pseudo-first-order rate expressions. It is usually prudent to begin with these best estimates of half-lives in air, water, soil, and sediment and perform a sensitivity analysis with the model to determine which processes are most important. One can return to the most important processes to assess whether more detailed rate expressions are necessary. An illustration of this mass balance approach is given in Figure 27.5 for benzol a Ipyrene. This approach allows a first-order evaluation of how chemicals enter the environment, what happens to them in the environment, and what the exposure concentrations will be in various environmental media. Thus the chemical mass balance provides information relevant to toxicant exposure to both humans and wildlife. 

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