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Interpretation of quantitative results

المؤلف:  Sue Jickells , Adam Negrusz (Editors)

المصدر:  Clarkes Analytical Forensic Toxicology

الجزء والصفحة:  90

2026-09-21

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Interpretation of quantitative results

In very general terms, soon after acute exposure, blood concentrations of volatile substances of 5–10 mg/L and above may be associated with clinical features of toxicity. In other words, pharmacologically effective concentrations of volatile substances are similar to those of in halational anaesthetics and are thus an order of magnitude lower than those observed in poisoning with relatively water-soluble compounds, such as ethanol. There may be a large overlap in the blood concentrations of volatile compounds attained after workplace exposure and as a result of deliberate inhalation of vapour. This has been demonstrated for toluene (Meredith et al. 1989; Miyazaki et al. 1990). Aside from individual differences in tolerance and possible loss of toluene from the sample prior to analysis, sample contamination, etc., the lack of a strong correlation between blood concentrations and clinical features of poisoning is probably due to rapid initial tissue distribution. Urinary excretion of 2-methylphenol provides a selective measure of toluene exposure for use in occupational and/or environmental monitoring (Table 4.3).