Benzopyrenes determined

Table III. Benzopyrenes Determined in Solvent-Refined Coal and Oil Shale Materials...

As described elsewhere in this chapter, alterations in the activity of a number of lung enzymes have been described after acute and chronic ozone exposure. With the possible exceptions of the sulfhydryl-containing enzyme succinic dehydrogenase and the cytochrome P-4 en me benzopyrene hydroxylase, it is difficult to determine whether these findings are due to a direct oxidative effect of ozone or are secondary to changes in protein synthesis, concentrations of intermediates, or destruction of cells or organelles. 

Fig. 26a and b. The effect of water content in the adsorbent on the retention volumes of standards in hexane (a) and determination of adsorbent activity a and monolayer volume (b) after reaching the critical conditions in binary solvents given in Fig. 25. Xo = 1.71 styrene, 2.02 naphthalene, 2.14 acenaphthylene, 3.02 benzopyrene-3,4 641...

Soo et al. (2002) studied tliB vitro release of hydrophobic Luorescent probes from PEO-b PCL micelles. Micelle solutions were placed in dialysis bags (MWCO 50,000) in a stirred water bath with a constant overLow of distilled water. This maintained the release environment at near perfect sink conditions, so the limited solubility ofthe probes in the medium did not affect release kinetics. Release was determined by removing aliquots ofthe dialysis bag contents and measuring Luorescently. Soo et al. found an initial burst release of probe followed by slow diffusional release. For the probes studies, benzopyrene and Cell-Tracker-CM-Dil, diffusion constants were ofthe order 10"15 cnnP/s. 

Table 4 shows the results of mineralization experiments of some selected compounds obtained with the described automatic arrangement. Whereas pentachloro phenol and benzopyren are degraded relatively quickly, lindane, dieldrin, and 4,4 -DDT show a comparable lower mineralization rate. The results prove the sensitivity of the test method. A mineralization rate lower than 1% can be determined without any analytical difficulties[9 ]. ... 

Originally, it was assumed that the (Q,m should always be unity and that the electron affinity should be obtained from the fixed intercept. Other experimental determinations of the electron affinities for CS2, CH3N02, tetracene, and benzopyrene demonstrate that Qan can be lower than 1. It is not expected that Qan is greater than 1 so the electron affinity is obtained by assuming it is 1, as in the case of benz[e]pyrene. If the intercept is lower than the average intercept, then the actual slope through the data should be used to obtain the electron affinity along with its associated errors [2-4]. 

It looks promising to determine the ratios between several frequently measured PAHs as chrysene, 1,2 benzopyrene, 3, benzopyrene,... 

They must be based on well defined standardized analytical techniques (and when necessary on the determination of specific components). They must be coordinated with the standards and limits proposed for other ways of exposure as for instance, the European Standards of EEC for drinking water "It is recommended that six compounds (fluoranthene 3,4 benzfluoranthene 11,12 benzfluoran-thene 11,12 benzperylene 3,4 benzopyrene, indeno (1,2,3-cd) pyrene) will be analysed and their concentrations should not exceed 0,2 ]Jg/l". 

Third passage log phase cultures of Syrian hamster fetal cells were treated as described in the table. Cultures treated with benzopyrene and Ni3S2 were exposed to benzopyrene for 24 h prior to treatment with the metal. Cultures were treated with the metal compounds three times using a two-day exposure for each treatment. Cells were then removed from the plate by trypsini-zation and the number of cells present in each plate was determined with a hemocytometer. Five thousand or ten thousand cells were replated to form colonies into 100 mm diameter plates and the number of surviving colonies in each plate was counted. Each number shown in the table is the mean of four tissue culture plates. 

Various workers [23-32] have studied the application of high performance liquid chromatography to the determination of PAHs in water samples. Hagenmaier et al. [31] used a reversed phase high-pressure liquid chromatography procedure for the determination of trace amounts of polycyclic aromatic hydrocarbons in water. Different column packing materials were tested, in conjxmction with non polar stationary phases of various polarities, for separation efficiency, detection limits and long-term stability. The method was suitable for concentrations as low as 2ng L" in a IL sample. Compoxmds studied included fluoranthene, benzofluoranthene isomers, benzopyrene and perylene derivatives. 

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