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Similarities between histological features of alcoholic hepatitis and obesity-related liver disease suggest a common pathogenic mechanism. Because intestinal bacteria can produce ethanol, it is conceivable that intestinally derived alcohol may contribute to fatty liver disease. An indirect way of measuring endogenous ethanol is to measure the breath ethanol concentration. In a previous study in ob/ob mice, breath ethanol decreased with a course of non-absorbable antibiotics, suggesting that the ethanol is derived from intestinal bacterial flora. The aims of this study were 1) to determine whether alcohol can be detected in the breath of human subjects, and 2) to assess whether there is any correlation between ethanol and obesity in patients with nonalcoholic steatohepatits (NASH) and control subjects without known liver disease.Breath ethanol concentration was determined in 21 patients with biopsy-proven NASH and in 10 control subjects by gas chromatography. An abnormal breath ethanol level was defined as two standard deviations above the mean value of the breath ethanol of lean controls.Minute quantities of ethanol were detected in the breath of human subjects who had not consumed alcohol in the recent past. Patients who were obese were more likely to have higher breath ethanol concentrations. Women also had higher breath alcohol than men. However, there was no difference between patients with NASH and controls. Severity of liver disease, as evidenced by cirrhosis, did not influence the breath ethanol concentration.Higher breath ethanol concentrations are observed in obese subjects than in leaner ones. It is possible that intestinally derived ethanol may contribute to the pathogenesis of NASH.

Studies involving the Ames Salmonella mutagenicity test and the Bacillus subtilis comptest have demonstrated that the soluble organic fraction of diesel particulate is potentially mutagenic and DNA damaging. The soluble organic fraction was extracted from exhaust particulate samples collected from four different diesel engines operated at specified conditions. For each fraction collected, an increase in the concentration of the organic material resulted in a subsequent increase in the number of histidine prototrophs obtained when this material was added to the histidine auxotrophic strains that comprise the Ames Salmonella test. Specifically, the number of induced revertants, for strains TA98 and TA100, ranged from less than one revertant per microgram of sample to 29 revertants per microgram of sample. The ability of these organic fractions to induce bacterial SOS functions also was determined by exposing competent cultures of Bacillus subtilis strain RUB827 to increasing concentrations of these extracts. With varying efficiencies, these samples were positive in their ability to induce the SOS system of B subtilis. Significantly, the toxicity of these mutagenic and DNA damaging samples never resulted in more than 95% killing, even for the highest concentrations tested in the Salmonella and B subtilis assay.

An account is given of the preparation, separation and detection of volatile fluorides. These fluorides are formed by the reaction of chlorine trifluoride with the elements in a specially designed PTFE reaction vessel enclosed in an HF coil. A comparison is also made of a spectroscopic detector with a katharometer for the detection of the fluorides. The separation of volatile fluorides has been reported to be partially successful on perfluorinated materials such as Kel-F oils or waxes on PTFE supports.1–3 The present communication describes a more detailed investigation of these separations and also compares the performance of a newly developed spectroscopic detector4 with a conventional katharometer detector.

The design and construction of a reactor injection assembly for the formation of volatile metal fluorides is described. The sample, in a chlorine trifluoride atmosphere, is heated with a radio-frequency induction heater and the volatile products passed into a hydrogen diffusion flame emission detector. Although this device is primarily intended for use in gas chromatography, this preliminary evaluation is concerned with its application to atomic spectroscopy.