Validation of an analytical method for determination of 13 priority polycyclic aromatic hydrocarbons in mineral water using dispersive liquid-liquid microextraction and GC-MS

Dispersive liquid-liquid microextraction (DLLME) combined with gas chromatography–mass spectrometry (GC–MS) was used for the extraction and determination of 13 polycyclic aromatic hydrocarbons (PAHs) in mineral water samples. In this procedure, the suitable combination of extraction solvent (500 μL chloroform) and disperser solvent (1000 μL acetone) were quickly injected into the water sample (10.00 mL) by Hamilton syringe. After centrifugation, 500 μL of the lower organic phase was dried under a gentle stream of nitrogen, re-dissolved in chloroform and injected into GC-MS. Chloroform and acetone were found to be the best extraction and disperser solvent, respectively. Validation of the method was performed using spiked calibration curves. The enrichment factor ranged from 93 to 129 and the recovery ranged from 71 to 90%. The linear ranges for all the PAHs were 0.10-2.80 ngmL-1. The relative standard deviations (RSDs) of PAHs in water by using anthracene-d10 as internal standard, were in the range of 4-11% for most of the analytes (n = 3). Limit of detection (LOD) for different PAHs were between 0.03 and 0.1 ngmL-1. The method was successfully applied for the analysis of PAHs in mineral water samples collected from Tehran. © 2016 by School of Pharmacy Shaheed Beheshti University of Medical Sciences and Health Services

Simultaneous determination of 13 priority polycyclic aromatic hydrocarbons in Tehran’s tap water and water for injection samples using dispersive liquid-liquid micro extraction method and gas chromatography-mass spectrometry

Polycyclic aromatic hydrocarbons (PAHs) are classified as persistent and carcinogenic organic pollutants. PAHs contamination has been reported in water. Many of relevant regulatory bodies such as EU and EPA have regulated the limit levels for PAHs in drinking water. In this study, 13 priority polycyclic aromatic hydrocarbons (PAHs) were determined in tap water samples of Tehran and water for injection. Dispersive liquid-liquid microextraction procedure combined with gas chromatography-mass spectrometry was used for the extraction and determination of PAHs in the samples. Under the optimized conditions, the range of extraction recoveries and relative standard deviations (RSDs) of PAHs in water using internal standard (anthracene-d10) were in the range of 71-90% and 4-16%, respectively. Limit of detection for different PAHs were between 0.03 and 0.1 ngmL-1. The concentration of PAHs in all tap water as well as water for injection samples were lower than the limit of quantification of PAHs. This is the first study addressing the occurrence of PAHs in water for injection samples in Iran using dispersive liquid-liquid micro extraction procedure combined with gas chromatography-mass spectrometry. © 2016 by School of Pharmacy

Validation of a method to assess occupational exposure to tert-buthyl mercaptan by gas chromatography- mass spectrometry (GC-MS)

زمینه و اهداف: ترشیو بوتیل مرکاپتان به عنوان یکی از مهمترین ترکیبات بودارکننده گاز طبیعی استفاده می­گردد. مواجهه با غلظت­های بالای این ماده، منجر به اثرات تحریک کنندگی در انسان­ می­شود. مواجهه شغلی با مرکاپتان‌ها با استفاده از کروماتوگرافی گازی با دتکتور فوتویونیزاسیون شعله­ای بر اساس روش NIOSH به شماره2542 تعیین می­گردد. هدف این مطالعه ارائه روشی برای نمونه برداری و آنالیز برخی ترکیبات بودار کننده در گاز طبیعی با استفاده از GC-MS می­باشد. مواد و روش­ها: در این مطالعه با استفاده از ستون BP-5 MS و با استاندارد داخلی 4-متیل تیوفنل ترکیب ترشیوبوتیل مرکاپتان آنالیز گردید. در این تحقیق منحنی استاندارد در گستره غلظتی   ppm 0.45-10 تهیه شد. تکرار پذیری روش در یک روز و چند روز بر اساس ضریب تغییرات ­(CV) محاسبه شد. بازیافت نمونه­های ترشیو بوتیل مرکاپتان به عنوان صحت روش گزارش گردید. تمام مراحل این مطالعه توسط کمیته اخلاق دانشگاه علوم پزشکی شهید بهشتی تایید گردید. یافته­ها: زمان ماند ترشیو بوتیل مرکاپتان و 4-متیل تیو فنل به ترتیب 4/05، 8/01 دقیقه مشخص شد. منحنی خطی با رگرسیون 0/99 بدست آمد. میانگین درصد بازیافت 6/6 ± 98/36تعیین شد. ضریب تغییرات درون روز و برون روز برای غلظت‌های استاندارد مختلف از ترکیب مدنظر در محدوده 7/2 – 0/46 بدست آمد. حداقل غلظت قابل تشخیص و قابل ارزیابی برای ماده مدنظر به ترتیب 0/037 و 1/84 میکروگرم در نمونه بدست آمد. نتیجه­ گیری: روش ارائه شده با GC-MS با پارامترهای اعتبار بخشی ارایه شده به عنوان جایگزین مناسب روش NIOSH پیشنهاد می‌شود. کلمات کلیدی:ترکیب ترشیوبوتیل مرکاپتان، گاز طبیعی، کروماتوگرافی گازی-طیف سنجی جرمیBackground and Aims: Tert-butyl mercaptan is used as an important odorant of natural gas. Exposure to high concentrations of this substance lead to stimulating effects in human. Occupational exposure to mercaptan is measured by gas chromatography - flame photometer according to NIOSH 2542. The purpose of this study was to develop a method for sampling and analyzing tert-butyl mercaptan using GC_MS. Materials and Methods: In this study, tert-butyl mercaptan was analyzed using BP-5 MS column and internal standard of 4-methyl thiophenol. Calibration curve was developed and evaluated in the range of 0.45-10 ppm. Repeatability of method was presented by inter- day and intra-day assay based on the coefficient of variation (CV). Recovery of tert-butyl mercaptan was reported as the accuracy of method. All procedures of this study were approved by Shahid beheshti University of medical Science Institutional Review Board. Results: Retention Time of tert-butyl mercaptan and 4-methylthiophenol were determined as 4.05 and 8.01 min, respectively. Calibration curve was evaluated by the regression of 0.99. The mean recovery percent was 98.68 ± 6.6. Intra-day and inter-day coefficient of variance for standard concentrations was ranged between 0.46-7.2 percent. The limit of detection and limit of quantitation were presented 0.037 and 1.84 μg/sample, respectively. Conclusion: GC-MS method by validated parameters was suggested as a suitable alternative for NIOSH method

Determination of benzoapyrene in traditional, industrial and semi-industrial breads using a modified QuEChERS extraction, dispersive SPE and GC-MS and estimation of its dietary intake

A fast and simple modified QuEChERS extraction method was developed for determination of Benzo[a]pyrene (BaP) in 137 traditional (Sangak), semi-industrial (Sangak) and industrial bread samples using spiked calibration curves by GC/MS. Sample preparation includes extraction of BaP into acetone followed by cleanup with dispersive solid phase extraction. The limit of detection and limit of quantification were 0.3 ng/g and 0.5 ng/g, respectively. The values for recoveries and RSD were calculated as 110.5-119.85% and 1 ng/g. BaP content in all industrial samples was lower than LOQ. Assuming the consumption of bread in Tehran and Shiraz is limited to these kinds of breads, the daily intake of BaP in Tehran and Shiraz population through bread consumption was estimated to be 170.6 and 168.7 ng/day, respectively. This is the first report concerning contamination of bread samples with BaP in Iran

Validation of an Analytical Method for Determination of Benzoapyrene Bread using QuEChERS Method by GC-MS

A fast and simple modified QuEChERS (quick, easy, cheap, rugged and safe) extraction method based on spiked calibration curves and direct sample introduction was developed for determination of Benzo[a]pyrene (BaP) in bread by gas chromatography-mass spectrometry single quadrupole selected ion monitoring (GC/MS-SQ-SIM). Sample preparation includes: extraction of BaP into acetone followed by cleanup with dispersive solid phase extraction. The use of spiked samples for constructing the calibration curve substantially reduced adverse matrix-related effects. The average recovery of BaP at 6 concentration levels was in range of 95-120%. The method was proved to be reproducible with relative standard deviation less than 14.5% for all of the concentration levels. The limit of detection and limit of quantification were 0.3 ng/g and 0.5 ng/g, respectively. Correlation coefficient of 0.997 was obtained for spiked calibration standards over the concentration range of 0.5-20 ng/g. To the best of our knowledge, this is the first time that a QuEChERS method is used for the analysis of BaP in breads. The developed method was used for determination of BaP in 29 traditional (Sangak) and industrial (Senan) bread samples collected from Tehran in 2014. These results showed that two Sangak samples were contaminated with BaP. Therefore, a comprehensive survey for monitoring of BaP in Sangak bread samples seems to be needed. This is the first report concerning contamination of bread samples with BaP in Iran. © 2016 by School of Pharmacy

Designing SQCRA as a Software to Semi-quantitative Chemical Risk Assessment in Workplace

Background & Objectives : The aim of chemical risk assessment is to identify and evaluate risks originated from chemicals usages. This study aims to design a practical tool for facilitating chemical risk assessment. Methods: The proposed software was derived from chemical risk assessment method which was recommended by Ministry of Human Resources of Malaysia. All of the processes in question are designed in operating system software. Based on some revisions, this software was developed using Visual Basic (VB) titled as SQCRA. The developed software was used for chemical risk assessment in Narges Vegetale Oil Company in Shiraz (center of Iran). Result: The output of software showed that the level of risk derived from sulfuric acid, phosphoric acid, aluminum sulphate, nickel catalyst, acetic acid used as a raw material were 2.4, 2.84, 2.3, 3.5 and 2.66, respectively. Moreover, risk rank and proposed control methods for each of these materials were determined. Conclusions : The developed software calculates the health risk level based on the degree of hazard and exposure in shorttime and without using risk matrix and chemical formula. After determining the risk rank, the software proposes the control procedures to reduce occupational exposure

Validation of an Analytical Method for Determination of benzo[a]pyrene in bread using QuEChERS method by

Abstract A fast and simple modified QuEChERS (quick, easy, cheap, rugged and safe) extraction method based on spiked calibration curves and direct sample introduction was developed for determination of Benzo[a]pyrene (BaP) in bread by gas chromatography-mass spectrometry single quadrupole selected ion monitoring (GC/MS-SQ-SIM). Sample preparation includes: extraction of BaP into acetone followed by cleanup with dispersive solid phase extraction. The use of spiked samples for constructing the calibration curve substantially reduced adverse matrix-related effects. The average recovery of BaP at 6 concentration levels was in range of 95-120%. The method was proved to be reproducible with relative standard deviation less than 14.5% for all of the concentration levels. The limit of detection and limit of quantification were 0.3 ng/g and 0.5 ng/g, respectively. Correlation coefficient of 0.997 was obtained for spiked calibration standards over the concentration range of 0.5-20 ng/g. To the best of our knowledge, this is the first time that a QuEChERS method is used for the analysis of BaP in breads. The developed method was used for determination of BaP in 29 traditional (Sangak) and industrial (Senan) bread samples collected from Tehran in 2014. These results showed that two Sangak samples were contaminated with BaP. Therefore, a comprehensive survey for monitoring of BaP in Sangak bread samples seems to be needed. This is the first report concerning contamination of bread samples with BaP in Iran

Occupational exposures and respiratory symptoms and lung function among hairdressers in Iran:a cross-sectional study

Abstract Objective: Exposures at hairdressers’ work have been reported to lead to an increased risk of several health outcomes. The present study aimed to investigate the relations between occupational exposures and respiratory symptoms and lung function among hairdressers in Iran. Methods: We conducted a cross-sectional study to compare potential respiratory effects among 140 women working as hairdressers to such effects among 140 women working as office workers (administrative personnel). Both groups worked in Shiraz, Iran. Respiratory symptoms were assessed by a standard respiratory questionnaire. The questionnaire also inquired about substances used and workspace conditions, including ventilation type. Lung function levels were measured by spirometry. Results: Respiratory symptoms, including cough, wheezing, shortness of breath, and chest tightness were significantly more frequent in hairdressers compared to the reference group (p < 0.05). After controlling for potential confounders, hairdressers had a prevalence ratio (PR) of 2.18 (95% CI 1.26–3.77) for cough, 9.59 (95% CI 1.004–91.73) for wheezing, 2.06 (95% CI 1.25–3.39) for shortness of breath, and 3.31 (95% CI 1.84–5.97) for chest tightness compared to the reference group. Lung function parameters (including VC, FVC, and FEV1) were significantly reduced in hairdressers (p < 0.001). Absence of air conditioning predicted greater reduction in lung function (p < 0.05) in the exposed. Decrease in FVC with normal FEV1/FVC in the exposed group suggested existence of restrictive lung function. Conclusions: This study provides evidence of increased prevalence of respiratory symptoms and restrictive lung function impairment among hairdressers in Iran