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Phenolic compounds are among the priority pollutants due to their adverse effects on human health and other living organisms. Advanced Oxidation Processes (AOPs) offer promising prospects for the removal of pollutants in water and wastewater due to their high efficiency as well as acceptable health and environmental effects. Persulfate, especially when used with iron, is far stronger than many other oxidants with respect to oxidation properties since it produces sulfate radicals which create a higher oxidation potential. In this research, efforts have been made to achieve the best conditions for phenol removal from aqueous environments by activating persulfate with iron ions. The experimental design was accomplished using the Taguchi statistical method and the Minitab 16 software. For the purposes of this study, four factors, each with five levels, were considered to determine the optimal conditions for phenol removal. The optimum conditions for phenol removal by integrated persulfate/iron ions were found to comprise a contact time of 120 minutes, a persulfate/iron molar ratio of 5/4, and PH=3. Phenol removal efficiencies of 94.93%±0.708 and 58.21%±0.675 were obtained under the optimum conditions for the experimental minimum (50 mg/l) and maximum (750 mg/l) phenol concentrations, respectively. The results revealed that among the parameters affecting the process, environmental pH with 54.80% and persulfate concentration with 11.05% have the highest and lowest effects, respectively. It is expected that this process is also capable of removing phenol from industrial wastewaters with removal efficiencies in the range of 59‒95%.

Introduction: Lung cancer is the second most common cancer in the world. Smoking occupational and environmental exposures are the most important causes of lung cancer. Cadmium is known as a human carcinogen due to its ability to increase lung cancer risk. This study estimates the general results of all studies on the relationship between cadmium and lung cancer. Material and Methods: In the present study, studies that evaluated the relationship between cadmium and lung cancer until May 2022 were searched and retrieved. From the funnel plot to determine the existence of diffusion skew, from the statistical tests Chi-squared test (x2) and I2 to determine heterogeneity, from the meta-regression method to identify the root of heterogeneity, and from the sensitivity analysis approach to identify the effect of each study on the result, it was generally used. This study performed all analyses with Stata statistical software version 15. Results: In this study, it was observed that the chance of developing lung cancer compared to the base group, in the people exposed to a higher dose than the base level of cadmium is equal to 1.31 (95% CI: 1.06-1.62; p-value = 0.024), which is statistically significant. Based on Egger’s test (p-value = 0.178) and Begg’s (p-value = 0.276), no diffusion bias was observed in this study. Conclusion: ccording to the final results of this review research, exposure to cadmium leads to a 31% increase in lung cancer risk, which is statistically significant. Therefore, cadmium is a risk factor for lung cancer.

Background. Prostate cancer is the second most common cancer in men and the fifth leading cause of death worldwide. Our aim in this study was to investigate the relationship between exposure to cadmium and the incidence of prostate cancer through conducting a systematic review and meta-analysis method. Methods. The Studies that investigated the relationship between cadmium and prostate cancer were searched and retrieved from the international databases until May 2022. (x2) and (I2) statistical tests were used respectively to determine the presence and size of heterogeneity; Egger's and Bagg's tests were used to determine the existence of diffusion bias; and meta-regression and sensitivity analysis were used to identify the source of heterogeneity. All analyses were performed by Stata (Version 15) statistical software. Results. It was observed that the relative risk of prostate cancer occurrence compared to the base group, in people exposed/exposed to a dose higher than the base level was equal to 1.05(95% CI:0.94-1.17; P=0.372); Meanwhile, no statistically significant relationship was observed between exposure to cadmium or exposure levels exceeding the baseline and prostate cancer. According to the results of Egger's test (P = 0.989) and Begg's (P= 0.787), diffusion distortion was not observed in this study. Conclusion. Based on the available evidence, although exposure to cadmium leads to an increase in the risk of prostate cancer, this risk increase is not statistically significant. Practical Implications. The World Health Organization should think with a more serious approach to the relationship between environmental health and cancers.

Oil spills from pipeline accidents can have long-lasting health effects on residents of polluted regions. Assessing the potential health risk of these accidents is crucial for effective environmental health management. This study analyzed the concentration of 2-OHNAP in urine and hair as biomarkers of PAHs exposure among the people living in a region with frequent oil pipeline incident in Iran. Fifty pairs of hair and urine samples were collected from residents along with demographic information and dietary habits via a questionnaire. The concentration of 2-OHNAP was analyzed using high performance liquid chromatography coupled with fluorescence detector (HPLC-FLD). 2-OHNAP was detected in 100% of urine and 88% of hair samples. The mean concentration of 2-OHNAP in urine was 16.65 ± 21.98 μg/g creatinine and in hair was 8.16±7.62 ng/g dry weight (dw). However, there was no significant correlations between the levels of 2-OHNAP in urine and hair. The mean values of HQ and CR were below 1 and 10-6, respectively. Moreover, some simulated health risk indices were near the threshold levels, and the carcinogenic risk above 70% of the simulated CRs was above 10-6 as well. Therefore, the health risk attributed to the exposure to the parent compound of 2-OHNAP in the study area is currently acceptable, but it is not negligible and may be worsened in the future. This study provides a valuable scientific information for regional decision makers and stakeholders about human health programs and identification of environmental health priorities.

Research objectives: Intertwined with modern life, air pollution is not a new phenomenon. Air pollution imposes a significant number of deaths and disease complications on society, and therefore it is very important to determine the extent of its effects on health in any society. This study sought to evaluate the concentration and short-term and long-term excess mortality attributed to PM2.5, NO2 and O3 observed in Shahrekord. Procedure: Hourly concentrations of PM2.5, O3, and NO2 measured at different stations of the Shahrekord Monitoring Network were obtained from the Shahrekord Department of Environment (DOE). Then, for different air quality monitoring stations, the average 24-hour PM2.5 concentration, the one-hour average NO2 concentration and the maximum 8-hour daily O3 concentration were calculated using Excel 2010. When the maximum 8-hour daily ozone level exceeds 35, it drops below 35 to calculate the SOMO35 index for modeling. Results: The death rates of IHD, COPD, lung cancer and ALRI and stroke related to PM2.5 were 176, 7, 0, 10, 105, respectively. The effect of ozone on respiratory mortality was zero. During the study period in Shahrekord, no respiratory mortality was determined due to ozone and acute lower respiratory tract infection (ALRI). this study is first ever study on health effects of air pollution in shahrekord city Conclusion: A significant number of deaths due to air pollutants in Shahrekord have been reported. It can be concluded that by designing and implementing strategies and measures to control air pollution, both health effects and economic losses are prevented.

Background and Objective: N-methylpyrrolidine is a highly potent solvent with toxic and adverse ecological properties that has historically been widely used in the chemical and petrochemical industries. Due to the health and safety، toxicity and environmental effects of effluents containing NMP، these effluents should be pre-treated before biological treatment methods. The aim of this study was to remove N-methylpyrrolidone by photo- Fenton process. Materials and Methods: For testing, solutions such as sulfuric acid, iron sulfate 7, oxygenated water, sodium hydroxide and distilled water were added to N-methypyrrolidine compounds in the reactor. Then, the removal process was investigated in two stages: complete mixing and adding solutions. Results: The results revealed that the Fenton process cannot be used successfully to treat the hypothetical refinery effluent containing NMP. However، the photo-phanton process mineralized and degraded the NMP composition. Increase in 30% H2O2 concentration to the optimal dose of 1 mL led to the highest degradation (94%) and decrease in COD level of solution (42.1%). Conclusion: It can be concluded that advanced oxidation by photo-phanton reaction can be a promising advanced oxidation technology for decomposition and pre-treatment of NMP-containing wastewaters for further biological treatment.

Surfactants are one of the most commonly found xenobiotics in municipal and industrial wastewater. The purpose of this study was to compare ultraviolet/ultrasonic (UV/US) and ultraviolet/zinc oxide (UV/ZnO) processes in the removal of LAS from aqueous media.In this study, a medium-pressure UV lamp (125 W), an ultrasonic device (400 W and 42 kHz), and ZnO nanoparticles (NPs) were used. The concentration of LAS was 0.5, 14, and 21 mg/L in all experiments. Contact time of 8, 16, and 24 minutes, pH of 3, 7, and 11, and NP concentrations of 50, 100, 150 mg/L were selected. Detergent extraction was performed using methylene blue active substances.The results showed that the efficiency of UV/US process in the removal of LAS was 89.35%, while the removal efficiency of UV/ZnO process was 81.27%. In both processes, the rate of detergent removal increased by elongating the contact time from 8 to 24 minutes. The efficiency of UV/US process in LAS removal was greater than that of the UV/ZnO process. The findings showed that the removal efficiency of UV/US process was directly correlated with pH, while it had an inverse correlation with the removal efficiency of UV/ZnO process.

Introduction: Inadequate air quality is one of the environmental hazards factors imposing a significant number of deaths and complications of diseases on society. Therefore, it is highly important to determine the extent of its effects on health in communities. This study sought to assessment the concentration and additional short- and long-term mortality attributed to Particulate Matter less than 2.5 µm (PM2.5), Nitrogen Dioxide (NO2) and Ozone (O3) were observed in Ahwaz from 2012 to 2018 using AirQ+. Materials and methods: Daily and hourly concentrations of PM2.5, ozone and NO2 were obtained from Department of Environment in Ahvaz. Then, the mean concentration of 2.5 PM2.5 for 24 h, the mean concentration of NO2 for 1 h and the maximum concentration of O3 for 8 h daily were calculated using Excel 2010. Finally, to calculate the annual sum of maximum daily 8-h ozone means over 35 ppb (SOMO35) index, concentrations above 35 were collected and entered into the software. Results: The mean seven-year concentrations of PM2.5, NO2 and O3 were 68.21 (±135.86%), 24.46 (±22.79%) µg/m3 and 24.48 (±13.77%) ppb, respectively. The death rates of Ischemic Heart Disease (IHD), Chronic Obstructive Pulmonary Disease (COPD), lung cancer and Acute Lower Respiratory tract Infections (ALRI) and stroke related to PM2.5 were 2023, 128, 110, 23, 802, respectively. The number of respiratory deaths attributed to ozone was 68. Conclusion: The results show a high number of deaths due to bad weather in Ahvaz. It can be concluded that by designing and implementing appropriate and correct solutions and decisions, both health and economic losses are prevented.

Background. Recently, an outbreak of a novel human coronavirus SARS-CoV-2 has become a world health concern leading to severe respiratory tract infections in humans. Virus transmission occurs through person-to-person contact, respiratory droplets, and contaminated hands or surfaces. Accordingly, we aim at reviewing the literature on all information available about the persistence of coronaviruses, including human and animal coronaviruses, on inanimate surfaces and inactivation strategies with biocides employed for chemical and physical disinfection. Method. A comprehensive search was systematically conducted in main databases from 1998 to 2020 to identify various viral disinfectants associated with HCoV and methods for control and prevention of this newly emerged virus. Results. The analysis of 62 studies shows that human coronaviruses such as severe acute respiratory syndrome (SARS) coronavirus, Middle East respiratory syndrome (MERS) coronavirus or endemic human coronaviruses (HCoV), canine coronavirus (CCV), transmissible gastroenteritis virus (TGEV), and mouse hepatitis virus (MHV) can be efficiently inactivated by physical and chemical disinfectants at different concentrations (70, 80, 85, and 95%) of 2-propanol (70 and 80%) in less than or equal to 60 s and 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute. Additionally, glutaraldehyde (0.5–2%), formaldehyde (0.7–1%), and povidone-iodine (0.1–0.75%) could readily inactivate coronaviruses. Moreover, dry heat at 56°C, ultraviolet light dose of 0.2 to 140 J/cm2, and gamma irradiation could effectively inactivate coronavirus. The WHO recommends the use of 0.1% sodium hypochlorite solution or an ethanol-based disinfectant with an ethanol concentration between 62% and 71%. Conclusion. The results of the present study can help researchers, policymakers, health decision makers, and people perceive and take the correct measures to control and prevent further transmission of COVID-19. Prevention and decontamination will be the main ways to stop the ongoing outbreak of COVID-19.

Fluoride pollution in subsurface water is a significant problem for different nations across the world because of the intake of excessive fluoride caused by the drinking of the contaminated subsurface. Water pollution by flouride can be attributed to the natural and human-made agents. Increased levels of fluoride in drinking water may result in the irretrievable demineralization of bone and tooth tissues, a situation called fluorosis, and other disorders. There has long been a need for fluoride removal from drinking water to make it safe for human use. Among the various fluoride removal methods, adsorption is the method most popularly used due to its cheap cost, ease of utilization, and being a scalable and simple physical technique. According to the findings of this study, the highest concentration of fluoride (0.1–15.0 mg/L) was found in Sweden and the lowest (0.03–1.14 mg/L) in Italy. We collected the values of adsorption capacities and fluoride removal efficiencies of various types of adsorbents from valuable released data accessible in the literature and exhibited tables. There is still a need to find the actual possibility of using biosorbents and adsorbents on a commercial scale and to define the reusability of adsorbents to decrease price and the waste generated from the adsorption method. This article reviews the currently available methods and approaches to fluoride removal of water.

Trifluralin is one of the most widely used herbicides, being accounted as the cause of cancer in human. In the present research, the UV/S2O82− and ZnO/UV processes’ efficiency in the removal of trifluralin was investigated. A lab scale equipped with a UV lamp was applied. The parameters were studied, including initial trifluralin concentration (0.4–1.2 mg/L), contact time (20–60 min), S2O82− concentration (20–60 μM), and ZnO concentration (50–150 mg/L). The remained trifluralin concentration was measured by HPLC. This study proved the trifluralin removal of 92.90 ± 1.6% and 87.91 ± 19.22% for UV/S2O82− and UV/ZnO processes in the best operation conditions (contact time of 60 min, the persulfate concentration of 40 μM, and the ZnO concentration of 100 mg/L). The optimal trifluraline concentrations were 1.2 mg/L and 0.6 mg/L for UV/S2O82− and UV/ZnO processes, respectively. In both processes, the removal efficiency of trifluralin increased significantly with increasing contact time. The findings exhibited that both processes UV/S2O82− and UV/ZnO followed the zero-order kinetic. The electrical energy consumed of UV/S2O82 and UV/ZnO was about 43.95 and 20.41 Kwh/kg, respectively. The results show that UV/S2O82− and ZnO/UV processes were appropriate as the effective treatment method for trifluralin removal. Therefore, it is proposed to study the performance of these processes as an environmentally friendly practice in full scale with real wastewater.

Nowadays, advanced oxidation processes, particularly photocatalyst process and catalytic ozonation by ZnO nanoparticles, are the most efficient method of eliminating pharmaceuticals. The purpose of this study was to compare the efficiency of ultraviolet/zinc oxide (UV/ZnO) and ozone/zinc oxide (O3/ZnO) techniques as advanced oxidation processes in the removal of trimethoprim (TMP) from aqueous solutions. The process consisted of 0.6 g/L of ozone (O3), pH = 7.5 ± 0.5, TMP with a concentration of 0.5–5 mg/L, ZnO with a dose of 50–500 mg/L, 5–30 min reaction time, and 30–180 min contact time with UV radiation (6 W, 256 nm) in a continuous reactor. The high removal efficiency was achieved after 25 minutes when ZnO is used in 1 mg/L TMP under an operational condition at pH 7.5. When the concentration of the pollutant increased from 0.5 to 1, the average removal efficiency increased from 78% to 94%, and then, it remained almost constant. An increase in the reaction time from 5 to 25 minutes will cause the average elimination to increase from 84% to 94%. The results showed that the efficiency of O3/ZnO process in the removal of TMP was 94%, while the removal efficiency of UV/ZnO process was 91%. The findings exhibited that the kinetic study followed the second-order kinetics, both processes. With regard to the results, the photocatalyst process and catalytic ozonation by ZnO nanoparticles can make acceptable levels for an efficient posttreatment. Finally, this combined system is proven to be a technically effective method for treating antibiotic contaminants.

A major concern about pharmaceutical pollution is the presence of antibiotics in water resources through their release into sewers where they cause bacterial resistance and enhanced drug-resistance in human-borne pathogens and growing microbial populations in the environment. The objective of this study was to investigate the efficiency of the advanced H2O2/ZnO oxidation process in removing ceftriaxone from aqueous solutions. For this purpose, an experimental study was conducted in which the SEM, XRD, and TEM techniques were employed to determine the size of Zinc oxide nano-particles. Additionally, the oxidation process parameters of pH (3-11), molar ratio of H2O2/ZnO (1.5-3), initial concentration of ceftriaxone (5–15 mg/L), and contact time (30-90 min) were investigated. Teh data thus obntained were subjected top statistical analysis using the SPSS (ANOVA test). XRD results revealeda hexagonal crystal structure for the nano-ZnO. TEM images confirmed the spherical shape of the nanoparticles. Finally, SEM images revealed that the Zn nanoparticles used in this study were less than 30 nanometers in diameter. Based on the results, an optimum pH of 11, a contact time of 90 minutes, and a H2O2/ZnO molar ratio equal to 1.5 were the optimum conditions to achieve a ceftriaxone removal efficiency of 92%. The advance H2O2/ZnO oxidation process may thus be claimed to be highly capable of removing ceftriaxone from aqueous solutions.

17β-Estradiol (E2) has a significant health risk to humans, even at the ng/L level, and is discharged to the aqueous environment through wastewater. Advanced oxidation processes were proposed as an efficient process for the removal of E2. In this study, a combination of ultraviolet-C (UV-C) and KMnO4 was applied for the removal of E2. Results have shown that the removal efficiency of E2 in pH 4 (acidic condition) was 93.80 ± 0.42%. But, removal efficiency in neutral (7) and alkaline (10) conditions was 78.3 ± 2.12% and 84 ± 0.71%, respectively. The effect of Fe+2, Ca+2, Mg+2, Mn+2, and Fe+3 ions (1 mg/L) was investigated in optimized pH (4). Mn+2, Fe+2, and Ca+2 ions enhanced the removal efficiency to 94.8 ± 0.84%, 95.55 ± 0.07%, and 94.7 ± 0.14%, respectively p>0.05, while Mg+2 and Fe+3 ions decreased the removal efficiency significantly to 76.15 ± 1% and 83.91 ± 0.3% p0.05. The result indicates that the rate of oxidation of E2 is related to the second exponent of the initial concentration of E2 for optimum pH and the presence of all ions. But, in the presence of humic substances, the first-order kinetic reaction was best applicable in describing oxidation of E2. Removal of chemical oxygen demand for E2 after 120 minutes’ of contact time at optimum pH (86 ± 4.2%) demonstrated mineralization of these compounds at acceptable levels. Results presented that the UV-C/KMnO4 process is efficient for the removal of hormones from the aqueous solution.

The presence of persistent organic pollutants and toxics (e.g., pesticides) in ground, surface, and drinking water resources combined with the inability of conventional treatment methods to remove these pollutants have led to the development of advanced oxidation processes. Nowadays, nanophotocatalyst processes are considered as clean and environmentally-friendly treatment methods that can be extensively used for removing contaminants. The objective of the present study was to determine the efficiency of the ultraviolet and zinc oxide (UV/ZnO) process in the removal of diazinon pesticide from aqueous solutions. For the purposes of this study, samples were adjusted in a batch reactor at five different detention times. The pH levels used were 3, 7, and 9. Irradiation was performed using a 125 W medium-pressure mercury lamp. The diazinon concentrations of the samples were 100 and 500 µg/L and the concentrations of zinc oxide nanoparticles were 50, 100, and 150 mg/L. The highest degradation efficiency was observed at pH 7 (mean = 80.92 30.3), while the lowest was observed for pH 3 (mean 67.11 24.49). Results showed that the optimal concentration of nanoparticles (6-12 nm) was 100 mg L-1.

Aim: The aim of this study was to reduce the amount of diazinon from aqueous media using chemical–thermal-activated watermelon rind. Materials and Methods: This experimental study was carried out in a laboratory. First, watermelon rind was activated by chemical–thermal method. Then, the effective parameters of the diazinon adsorption process, including the initial concentration of diazinon (0.17–1 μg/L), pH (3–10), adsorbent amount (0.05–1 g/l), and contact time (30–100 min), were investigated and optimized. The amount of residual diazinon was measured by high-performance liquid chromatography. In this study, Taguchi method was used to determine the sample size and statistical analysis. Furthermore, in this study, to describe the adsorption equilibrium, Freundlich and Langmuir isotherm models were used. Results: The results showed that under an optimal pH of 6, the equilibrium time of 30 min, the amount of adsorbent 1 g/L, and the initial concentration 0.17 μg/L, the elimination efficiency of diazinon was 95.1%. Furthermore, the results of isothermic studies have shown that the removal of diazinon follows the Freundlich model (R2 = 0.921). Conclusion: Chemical–thermal-activated watermelon rind can effectively be used to remove low concentrations of diazinon from aqueous solutions.

Introduction: Assessing the conformity rate of educational programs with professional needs can lead to identify the weaknesses of such programs and provide the opportunity for their improvement. This study aimed to investigate the viewpoint of environmental health engineering graduates about conformity rate of the curriculum with their professional needs in Charharmahal and Bakhtiari province. Methods: This descriptive cross-sectional study was performed on 100 environmental health engineering graduates in 2013. The data was collected through a researcher-made questionnaire consisted of two sections: demographic (7 questions) and questions related to all specialized courses (42 questions) with a three-point rating scale (low, medium and high). The collected data were analyzed using descriptive statistics. Results: The results showed that the most suitable courses were inspection and control of food (both theoretical and practical), solid waste, disinfection and water treatment with 72.5%, 67.2%, 56.2%, 55%, and 53.8% conformity rates, respectively and showed that these courses had the most conformity with professional needs. Other courses such as mapping, fluid mechanics, hydraulics, pump and engine, and industrial wastewater with 66.2%, 58.8%, 57.5%, 56.3% and 51.2% respectively, had the least conformity with professional needs. Conclusion: Professional needs of environmental health engineering graduates were not fully covered by their curriculum. It seems necessary to change the educational programs and provide necessary means and facilities in order to achieve the professional objectives and train skilled and productive human resources.

Aim: The aim of this study was to evaluate the rate of contamination with Escherichia coli, coliforms, and Staphylococcus aureus in raw milk from Shahrekord city, Iran. Materials and Methods: In this study, 300 raw milk samples were collected randomly from five regions, namely northeast, east, southeast, south, and southwest regions of Shahrekord city according to stratified random sampling design. Samples were analyzed for Total plate count (TPC), Staphylococcus aureus, coliform, and E. coli. Results: Out of 300 samples of raw milk, contamination with coliforms, E. coli, and S. aureus was observed in 237 (79%), 207 (69%) and 125 (41.66%) samples, respectively. The highest rate of contamination was in the samples from southwest region with coliforms, E. coli, and S. aureus were present in 30 (100%), 29 (96.66%), and19 (63.33%) samples, respectively (p