Journal of Health and Safety at Work

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Introduction: Mercury, in different form can induce adverse effects on various organs especially central nervous system. The aim of this study was to determine concentration of mercury in inhalation and urine of the exposed worker and to investigate the prevalence of probable neurobehavioral disorders.
 

Material and Method: The present case-control study was conducted among workers of a unit in a petroleum industry. The study population consisted of 52 workers as case and 63 workers as control groups. The mercury concentration in air and urine was measured according to NIOSH 6009 standard and using the cold vapor atomic absorption spectrophotometer (CV-AAS). Demographic data and neurobehavioral disorders were collected using a self-reported questionnaire. Pearson correlation coefficient, multiple regression tests and SPSS v24 were used to analyze the data.
 

Result:  Air concentration of mercury was 0.062 ± 0.0014 mg/m3  which was higher than the recommended threshold by NIOSH and ACGIH. In addition, there was a significant difference between urinary concentration of mercury in the case (37.73 ± 13.01 µg/g cratinine) and control (5.93 ± 4.76 µg/g cratinine) groups (p=0.03 6). Based on the multivariate logistic regression model, significant relationships were found between memory loss, sleep disturbance, and urine mercurial concentrations and, between memory loss, moody, muscle weakness and air mercurial concentration.
 

Conclusion: The values of Hg in blood and urine workers who worked in investigated unit were significantly higher than recommended threshold values. In addition, the Hg concentration in urine was related to some of neurobehavioral disorders.

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Introduction: Evaluation of air pollutants using green microextraction methods that do not require solvents and allow for sampling and analysis in a single step has received attention. In this study, the needle trap microextraction method was developed and the hydroxyl fullerene adsorbent was used for benzene sampling in air. 
Material and Methods: Needle traps of identical length were filled with the selected adsorbent, and a standard chamber was used to generate specific benzene concentrations for sampling. Subsequently, the variables influencing the performance of the needle trap—specifically, sampling and desorption parameters—were optimized to achieve maximum efficiency using response surface methodology and Design Expert 11 software. Finally, the efficiency of the developed method was evaluated in a real-world environment and compared with the NIOSH 1501 method.
Results: Sampling temperature and humidity had an inverse relationship with the peak response rate, such that the sampler performed better at low temperature and humidity. The adsorbent’s ability to retain the analyte, despite its high vapor pressure, was deemed satisfactory, with analyte loss after 5 days measured at 5%. The maximum desorption occurred at 275°C and 3 minutes. The instrumental and quantitative detection limits were calculated to be 0.011 µgL-1 and 0.029 µgL-1 of air, respectively. The relative standard deviation (RSD) as an indicator of the repeatability of the method under study was also 5.38%. In a comparative study, the performance of the needle trap was evaluated to be better than the NIOSH method. 
Conclusion: The needle trap method and the hydroxyl fullerene nanostructure adsorbent have a good performance in sampling benzene in air and are recommended for occupational and environmental monitoring.