Noninvasive methods in environmental medicine - biomonitoring

Quantitative analysis of benzene, toluene, and xylenes in urine by means of headspace solid-phase microextraction

A simple method for benzene, toluene, and xylenes (BTX) quantitative analyses in human urine was developed, using headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled to mass spectrometry detection in the single ion monitoring mode. The developed method is solventless, non-invasive, requires small volume of sample (1 ml), shows high selectivity, sensitivity, repeatability, and linearity (correlation coefficients >0.998), providing a useful alternative to assess human exposure to BTX compounds due to occupational reasons or eventual exposure to organic solvents. Detection limit varies from 0.28 to 0.5 ppb (v/v).

Passive smoking, excretion of metabolites, and health effects: results of the Leipzig's Allergy Risk Study (LARS)

Over a 5-yr period, the Leipzig's Allergy Risk Study (LARS) investigated the influence of typical indoor-contaminant burdens on the development of allergies and upper respiratory tract infections in allergy-prone children. Typical indoor volatile organic compounds (VOCs) and excretion of certain VOC metabolites in urine were measured in children 3 yr of age. Data analyses were based on parent-completed questionnaires, exposure measurements, and medical examinations. Evaluation of passive smoking was of special interest. Generally, residences with a high burden of passive smoking had higher benzene concentrations than residences inhabited by nonsmokers. Obstructive bronchitis was observed more frequently in children exposed to increased concentrations of benzene, as well as toluene, styrene, and m,p-xylene. In addition, atopic symptoms were associated with excretion of certain VOC metabolites. For example, the authors found an association between eczema and exposure to toluene and between eczema and increased excretion of the toluene metabolite S-benzylmercapturic acid. The results suggest that if an association with certain health effects is to be demonstrated, evaluation of external exposures should be supplemented with evaluations of internal exposure.