Mercury determination in work place air and human biological samples based on dispersive liquid-liquid micro-extraction coupled with cold vapor atomic absorption spectrometry

Mercury as a toxic heavy metal is important factor must be determined and controlled in work place air and human biological samples. It should be mentioned that, mercury (Hg) get distinguished from other toxic environment pollutants, due to their non-biodegradability which accumulate in living tissues of human body. By NIOSH method, the briefing work place air of worker was measured by flow injection cold vapor atomic absorption spectrometry (FI-CV-AAS). For separation and preconcentration mercury from blood/urine samples, a new procedure based on benzyl 1H-pyrrole1-carbodithioate (BPDC; C12H11NS2 ) was used by ultrasonic liquid-liquid micro-extraction (ULLME) coupled with cold vapor atomic absorption spectroscopy (CV-AAS). The influences of various analytical parameters including pH, BPDC concentration, sample volume and ionic liquid volume were investigated. The quantitative recoveries and enrichment factor were obtained more than 95% and 9.8, respectively at pH=7. The detection of limit (LOD) and detection of quantification (LOQ) of mercury were 30 ng L^-1 and 0.1 μg L^-1 respectively. In order to calculate the validation and accuracy of proposed method, the certified reference materials (NIST, CRM 3133 Lot 061204) was used and analyzed by ULLME-CVAAS. So, proposed method had good potential for preparation and preconcentration mercury in human blood / urine samples of worker and workplace air before analysis.