Volatile organic chemical mixtures

Mortensen B, Osvoll PO, Woldbaek T. In vitro screening for metabolic interactions among frequently occurring binary mixtures of volatile organic chemicals in Norwegian occupational atmosphere. Pharmacol Toxicol 1998 83(2) 49-56. 

Krishnan and colleagues developed an approach to the PBPK analysis of complex mixtures in which the toxicologic interactions of binary mixtures are first combined in the affected and modeled target tissue [30]. An example for a mixture of volatile organic chemicals (m-xylene, toluene, ethylbenzene, dichlo-romethane, and benzene) that interact via competitive inhibition was devel-oped.The approach requires thatPBPKmodels be available for each component models are interconnected by Kt values and, naturally, by substrate concentrations—here, in the liver. It is necessary that all binary interactions be characterized. For a mixture of n components, the number of binary interaction experiments performed to determine K, values will be n(n - 1)12. While not indicated, it seems that some reduction of resources would be... 

Price K, Krishnan K. 2011. An integrated QSAR-PBPK modelling approach for predicting the inhalation toxicokinetics of mixtures of volatile organic chemicals in the rat. SAR QSAR Environ Res 22 107-128. 

Asphalts are dark brown or black solids or semi-solids foimd in the natural state and are also produced by the refining of petroleiun. Raw asphalt is a eomplex mixture of bitumen and low-volatile organic chemicals that are recovered from petroleum refinery residues or natural deposits. Bitumen is ageneric name applied to various mixtures of hydrocarbon. The American Society for Testing and Materials has the following standard definitions for asphalt. 

Essential is also used as the adjective form of the noun essence The mixtures of substances that make up the fragrant material of plants are called essential oils because they contain the essence that is the odor of the plant The study of the composition of essential oils ranks as one of the oldest areas of organic chemical research Very often the principal volatile component of an essential oil belongs to a class of chemical sub stances called the terpenes... 

If nonvolatile liquids are to be used to avoid the problems associated with volatile organic solvents, then it is very desirable that there is some convenient way of recovering the reaction products from the liquid. This approach is used in the biphasic systems described in Chapters 2-5. In the fluorous biphase (Chapter 3), reagents and catalysts are fine-tuned by adding perfluoroalkyl chains, known as ponytails , to ensure that only those chemicals will mix with the fluorous layer. Purification is simply a matter of separating the two phases. Transition metal catalysts with fluorous ligands will remain in the fluorous phase, and the whole catalyst-solvent mixture may be reused for another batch of reactions, as shown schematically in Figure 1.20b. 

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