A b s t r a c t
Background: Exposure to mercury (Hg) as a heavy metal can cause health effects. The objective of this study was to assess occupational exposure to Hg in a chlor-alkali petrochemical industry in Iran by determining of Hg concentrations in air, blood and urine samples. Methods: The study was performed on 50 exposed subjects and 50 unexposed controls. Air samples were collected in the breathing zone of exposed subjects, using hopcalite sorbents. Analysis was performed using a cold vapor atomic absorption spectrophotometer (CV-AAS) according to NIOSH analytical method 6009. For all participants, blood and urine samples were collected and then transferred into sterile glass tubes. After micro-extraction with ionic liquid and back extraction with nitric acid, Hg concentrations in blood and urine samples were determined by CV-AAS. Results: The mean concentration of air Hg was 0.042± 0.003 mg/m3. The mean concentrations of Hg in blood and urine samples of exposed subjects were significantly higher than unexposed controls (22.41± 12.58 versus 1.19± 0.95 μg/l and 30.61± 10.86 versus 1.99± 1.34 μg/g creatinine, respectively). Correlation of air Hg with blood Hg, urine Hg and blood Hg-urine Hg ratio were significant statistically (P< 0.05). Conclusions: The values of Hg in blood and urine samples of chlor-alkali workers were considerably high. Correlation coefficients showed that blood Hg and blood Hg-urine Hg ratio are better indicators than urine Hg for assessing occupationally exposed workers in terms of current exposure assessment.
Hamid SHIRKHANLOO, Farideh GOLBABAEI, Hamid HASSANI, Farrokh EFTEKHAR, Mohammad Javad KIAN
Results and discussion
Based on the preliminary experiments, the retention of Pb (II) and Ni (II) ions on a GO-packed micro-column was chosen for preconcentration of the metal ions and their subsequent determination by FAAS. Hence, in order to obtain quantitative recoveries of Pb (II) and Ni (II) ions with good sensitivity and precision, the presented SPE system was optimised for various analytical parameters.