Determination of low carboxyhemoglobin blood levels by gas chromatography

Carbon monoxide (CO) is one of the anthropogenic environmental pollutant. An essential source of this compound, especially in indoor air, is tobacco smoke, which itself contains high amount of the compound. CO from tobacco smoke states the risk not only for active smokers but also for passive ones. Carboxyhemoglobin HbCO blood level is a biomarker of exposure to CO. The aim of the study was to develop method of HbCO analysis by gas chromatography based on quantitative determination of released CO from analyzed HbCO. Before developing of the method the authors stated that the method should require only small amount of the blood for analysis and be enough sensitive to determined HbCO level in persons exposed to low concentrations of CO including passive smokers. A specific reactor for quantitative release of CO from blood sample was developed. The process of CO release was caused by internal mixing of the blood sample with releasing agent K 3[Fe(CN) 6] and stimulated by internal mixing of the blood sample with external rotating magnetic field. The method for preparing calibration solutions was developed. The method was calibrated for two ranges of HbCO concentrations (0–2.5% and 0–15%). The HbCO levels were determined in 0.15 ml blood samples taken from the finger tips of passive smokers exposed to environmental tobacco smoke with different intensities. The determined HbCO levels varied from 0.31% to 2.19% of total hemoglobin.