Relationships between levels of volatile organic compounds in air and blood from the general population

Abstract

The relationships between levels of volatile organic compounds (VOCs) in blood and air have not been well characterized in the general population where exposure concentrations are generally at parts per billion levels. This study investigates relationships between the levels of nine VOCs, namely, benzene, chloroform, 1,4-dichlorobenzene, ethylbenzene, methyl tert-butyl ether (MTBE), tetrachloroethene, toluene, and m-/p-and o-xylene, in blood and air from a stratified random sample of the general US population. We used data collected from 354 participants, including 89 smokers and 265 nonsmokers, aged 20-59 years, who provided samples of blood and air in the National Health and Nutrition Examination Survey (NHANES) 1999-2000. Demographic and physiological characteristics were obtained from self-reported information; smoking status was determined from levels of serum cotinine. Multiple linear regression models were used to investigate the relationships between VOC levels in air and blood, while adjusting for effects of smoking and demographic factors. Although levels of VOCs in blood were positively correlated with the corresponding air levels, the strength of association (R 2 ) varied from 0.02 (ethylbenzene) to 0.68 (1,4-DCB). Also the blood-air relationships of benzene, toluene, ethylbenzene, and the xylenes (BTEX) were influenced by smoking, exposure-smoking interactions, and by gender, age, and BMI, whereas those of the other VOCs were not. Interestingly, the particular exposure-smoking interaction for benzene was different from those for toluene, ethylbenzene, and the xylenes. Whereas smokers retained more benzene in their blood at increasing exposure levels, they retained less toluene, ethylbenzene, and xylenes at increasing exposure levels. Investigators should consider interaction effects of exposure levels and smoking when exploring the blood-air relationships of the BTEX compounds in the general population.

Exhaled breath analysis, a simple tool to study the pathophysiology of obstructive sleep apnoea

“…Unfortunately, the aforementioned factors have been generally poorly accounted for and controlled in studies with OSA. In addition, the levels of some exhaled VOCs relate to BMI [95] which fact should also be taken into consideration, especially in OSA. Not surprisingly, exhaled volatile compound pattern was different in obesity [96].…”

Benzene exposure among auto-repair workers from workplace ambience: A pioneer study from Pakistan

“…According to Wan et al [20], BMI and the duration of exposure are among those factors which may impact the prognosis of chronic benzene poisoning in genetically susceptible persons. Lin et al [21] found in his study that the blood-air association with benzene and other related derivatives are influenced by smoking, age and also by BMI. Therefore, this study shows that the blood level of xenobiotics is influenced by a number of factors related with the occupational environment.…”

Self-collected urine sampling to study the kinetics of urinary toluene (and o-cresol) and define the best sampling time for biomonitoring

“…The body of evidence is growing that determination of urinary solvents per se may be a useful tool in evaluating low levels of exposure and for facing problems of biomarker specificity and sensitivity (Fustinoni et al 2005a;Imbriani and Ghittori 2005;Lin et al 2007; Jakubowski Estimates were made assuming inhalation as unique exposure route, pulmonary uptake of 50 and 86% of inhaled dose, pulmonary ventilation of 10 L/min, and 1 ml/min renal filtration. In the last row the arithmetic mean value and standard deviation (SD) are reported -Ochocka, 2005).…”

“…In our view the most appealing characteristic of unmetabolized organic compounds in biological fluids is the high specificity, so they can be also applied at very low airborne exposures (Fustinoni et al 2005a;Lin et al 2007). This is a relevant property in a scenario where occupational exposure limit values, as well as work exposure, tends to decrease with time, while pollution of living environments is becoming a public concern.…”