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The determination of octanol-water partition coefficients (log K(ow)) is important for the prediction of the fate of organic pollutants in the environment. Traditionally, log K(ow) values are determined by shake-flask, estimated by, e.g., HPLC retention data, or calculated, e.g., from ClogP. In this paper, an alternative approach is reported that allows log K(ow) to be estimated from solid-phase microextraction (SPME) data. Previously reported attempts to correlate SPME data with log K(ow) are discussed. The results obtained in this work for six phenols, using an 85 μm polyacrylate-coated fiber, indicate that SPME is a viable method for estimating log K(ow) values <3.5.

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The response of bio®lters to varying periods of starvation and to changes in inlet concentrations of a mixture of toluene and xylene have been tested in laboratory-scale bio®lters packed with a mixture of Perlite and compost. These results have been mathematically modelled taking the emission of carbon dioxide as a proxy for kinetics measurements. The use of CO 2 is a more practical approach than that of kinetics based upon batch experiments on pure cultures. A simpli®cation of Zarook's method, our model produced good outlet predictions given small changes in the inlet concentration of toluene and xylene. But for more stressful situations, like the resumption of the feed after periods of starvation, the use of carbon dioxide proved to be inappropriate as an indicator of the biomass activity, greatly overestimating bio®lter performance. This suggested either the occurrence of cryptic growth (as a result of the stress in¯icted on the biomass) or perhaps the utilisation of the compost as a carbon source.

Twenty-two patients were investigated during acute attacks of erythema nodosum with a series of tests for circulating immune complexes. Nineteen had bilateral hilar lymphadenopathy and were considered to have sarcoidosis. Evidence of circulating immune complexes was found in 18, out of 22 patients (including 15 out of the 19 cases of sarcoidosis). The most frequent abnormality was the detection of elevated levels of C3 breakdown products (C3i), which were found in 14 out of 18 tests. The test results returned gradually to normal as symptoms subsided in 20-40 days, but 2 patients still showed abnormalities at 40 days despite the disappearance of symptoms. It is concluded that free immune complexes appear in the circulation during the early stages of acute sarcoidosis and gradually disappear as symptoms subside.

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