H. Aghaei, H. Kakooei, S.j. Shahtaheri, F. Omidi, S. Arefian, K. Azam,
Volume 3, Issue 4 (2-2014)
Abstract
Introduction: PAHs are organic compounds with benzenic rings that releas from hot asphalt as incomplete combusting. These compounds are one of the major concern in scientific societies, workplace and environment due to their stability, bioaccumulation, carcinogenic and mutagenic effects. Since asphalt workers are exposed to PAHs frequently in their job, in this study it was attempted to evaluate respiratory exposure of asphalt workers to PAHs in their breathing zone.
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Material and Method: In this study air samples of the asphalt workers were collected in accordance with the NIOSH 5506 method using PTFE filter and XAD-2 adsorbent. The ultrasonic bath and acetonithrile are used in order to extract the analytes from the filter and adsorbent. Also, the samples were analyzed by HPLC-UV.
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Result: In all samples, Finisher assistance and oilman with 1754.48 ng/m3 , 24.65 ng/m3 had maximum and minimum exposed to ∑PAH, respectively. Among the PAHs compounds, which asphalt workers exposed to, Naphtalene had the highest concentration. Among different asphalt workers tasks, screedman expoused to PAHs, had a significant difference.
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Conclusion: Evaluation of Polycyclic aromatic hydrocarbons concentrations in the breathing zone of asphalt workers indicated that exposure to these compounds were below the occupational exposure limits recommended by NIOSH, OSAH, ACGIH and Iranian OEL. Due to the highly carcinogenic potential of some of these compounds and absence of occupational exposure limits for these compounds, likes Chrysene and Benzo (a) Anthracene, it is strictly recommended to employ engineering controls and using suitable PPEs. This study also indicated that the exposure to PAHs in the most asphalt workers tasks had significant differences, and it can be due to proximity of the workers to the source of hot asphalt and also exposure to the exhaust gases that releasesd from the construction machinery.
Nematullah Kurd, Abdulrahman Bahrami, Abbas Afkhami, Farshid Ghorbani Shahna, Mohammad Javad Assari, Maryam Farhadian,
Volume 13, Issue 3 (9-2023)
Abstract
Introduction: Toluene, benzene, xylene, and ethylbenzene (BTEX) belong to the class of monocyclic aromatic hydrocarbons and are identified as toxic volatile compounds due to their harmful properties. The reliable biomarkers for occupational exposure to these toxic compounds are hippuric acid (HA), trans,trans-muconic acid (tt-MA), mandelic acid (MA), and methylhippuric acid (MHA), which correlate with toluene, benzene, ethylbenzene, and xylene, respectively.
Material and Methods: A novel magnetized imine-linked covalent organic framework (Fe3O4@TFPA-Bd) was synthesized, marking its inaugural use as a sorbent in microextraction by packed sorbent (MEPS). The synthesis of Fe3O4@TFPA-Bd was executed in a straightforward and efficient manner, using Fe3O4 nanoparticles as the magnetic core and benzidine (Bd) and Tris (4-formyl phenyl) amine (TFPA) as the structural building blocks. This newly produced sorbent was tested for the microextraction of hippuric acid (HA), mandelic acid (MA), trans, trans-muconic acid (tt-MA), and m-methyl hippuric acid (m-MHA) from urine samples, which were then analyzed using high-performance liquid chromatography (HPLC). In order to optimize the extraction performance, parameters like sample volume, elution volume, extraction cycles, pH, and sample solution temperature were thoroughly adjusted. The synthesized adsorbent underwent thorough characterization via scanning and transmission electron microscopy (SEM and TEM), Fourier transforms infrared spectrometer (FTIR), and X-ray diffraction (XRD).
Results: The developed method showcased promising attributes: low detection limits (0.02 µg/ml for tt-MA, S/N=3), low quantification limits (0.06 µg/ml for tt-MA, S/N=10), a solid linear range (0.5-320 µg/ml for MA, R > 0.99), and commendable intra- and inter-day precision (2.4%-4.3% and 3.1%-7.8%, respectively) for volatile organic compound (VOC) biomarkers. Furthermore, the method demonstrated recoveries in the 81-87.5% range for spiked samples, indicating its practicality and effectiveness.
Conclusion: The developed procedure was suitable for the determination of BTEX biomarkers from urine samples and can be an alternative to previous methods.
