Measurement of polycyclic aromatic hydrocarbons in edible oils and potential health risk to consumers using Monte Carlo simulation, southwest Iran.

Persistent organic pollutants, such as polycyclic aromatic hydrocarbons, are hazardous trace contaminants frequently observed in food ingredients, such as edible oils. This study aimed to measure PAHs in forty brands of edible oils marketed in southwest Iran. Additionally, we characterized the daily intake of MOE and ILCR using Monte Carlo simulation. To analyze the content of PAHs, the liquid-liquid extraction method followed by GC-MS was utilized. The average concentration of PAHs was mostly lower than the maximum value for individual PAH (2 µg/Kg); however, the average concentration of fluorene (3.86 µg/Kg) and benzo(a)anthracene (3.13 µg/Kg) was more than the permitted level. The highest residual concentrations of PAHs were mostly observed in canola and corn oils. The daily intake of BaP and 4-PAH for 95% of consumers was 0.01 ng/kg BW/day and 0.04 ng/kg BW/day, respectively. Also, MOE was more than 10,000 for the percentiles of 5%, 50%, and 95%. The modeled ILCR showed that consumption of oil does not currently pose a cancer risk for Iranian consumers due to PAHs exposure. Concerning potential health risks, consumption of edible oils is safe; however, regular monitoring and assessment are required.

4-Chlorophenol degradation using ultrasound/peroxymonosulfate/nanoscale zero valent iron: Reusability, identification of degradation intermediates and potential application for real wastewater.

In this study, nanoscale-zero valent iron (nZVI) was synthesized and its function was assessed in ultrasound (US)/peroxymonosulfate (PMS)/nZVI process to degrade 4-chlorphenol (4-CP). The influential operation parameters of US/PMS/nZVI were evaluated on 4-CP degradation. 95% of 4-CP was degraded during 30 min under the conditions of pH = 3.0, nZVI = 0.4 g/L, PMS = 1.25 mM, US power = 200 W. The rate constants of 4-CP degradation for US/PMS/nZVI, PMS/nZVI, US/PMS and US/nZVI were 0.1159, 0.03, 0.0134 and 0.0088 min-1 respectively. Simultaneous application of US and nZVI synergistically increased 4-CP degradation and PMS activation. nZVI was compared with Fe2+, Fe3+ and micro-ZVI and their results indicated high performance of nZVI compared to others. Reusability of nZVI was examined in four cycles. nZVI exhibited that reusability was acceptable in three runs. The results of effect of anions showed that phosphate had significant inhibitory effect on 4-CP degradation in US/PMS/nZVI process. The scavenging experiments indicated that hydroxyl radical had more contribution compared to sulfate radical. Intermediates of 4-CP degradation were identified including five aromatic compounds. Reaction pathway of 4-CP degradation was proposed. Finally, the performance of US/PMS/nZVI process was evaluated on real petrochemical wastewater. The results showed that US/PMS/nZVI can be a suitable pretreatment for biological treatment.