Many, but not all, of the effects of caffeine are mediated via the sympathetic nervous system. The effect of caffeine on lipid mobilization in resting conditions can be interpreted in 2 ways: lipid mobilization alone is insufficient to drive lipid oxidation, or large increments in lipid turnover result in small increments in lipid oxidation.

The aromas of a reference green Mexican coffee (Arabica) and of a coffee from the same origin, but having a pronounced earthy/mouldy off-taint, were characterised. From comparison of the two aroma profiles, the compounds causing the defect were detected by gas chromatography olfactometry, isolated and concentrated by preparative bi-dimensional gas chromatography, and characterised by gas chromatography-mass spectrometry. Six compounds participated in the off-flavour. Geosmin, 2-methylisoborneol, 2,4,6-trichloroanisole were found to be the main culprits, while three methoxy pyrazines (2-methoxy-3-isopropyl/-3-sec-butyl/-3-isobutyl pyrazine) contributed to a lesser extent to the earthy/ green undertone. The occurrence of the off-flavour could tentatively be linked to post-harvest drying.

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A direct reading method is described for the measurement of tetrachloroethylene and 1,1,1-trichloroethane in breath for concentrations ranging from 2.5 to 30 ppm. It is based on colorimetric detector tube technology and consists of a two-step procedure: 1) total breath sampling in a bag and 2) analysis of the bag's content by detector tubes for the solvent and carbon dioxide. The latter is used to take into account dead space dilution and possible hyper- or hypoventilation. The method is tested in volunteers experimentally exposed to tetrachloroethylene and 1,1,1-trichloroethane and in workers occupationally exposed to tetrachloroethylene. Its results are compared with a reference gas chromatographic method. The agreement between the methods is good, with a systematic proportional error of less than +13% for tetrachloroethylene. Repeated measurements show standard deviations ranging from 6% to 39% of the tested concentrations.