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Dust storms and particulate matters had been increased due to climate change in the Middle East. On the other hand, urbanization and industrialization raised levels of gaseous air pollutants in all big cities. In the current study, air pollution information collected from Environmental Protection Agency of Khuzestan and Tehran containing hourly O(3), NO(2), CO, SO(2), PM(10) and PM(2.5) concentrations between 2014 and 2015. This study evaluated the air quality of these two cities by Air Quality Index (AQI). As a result, mean concentrations of O(3), NO(2), PM(10) and PM(2.5) were higher in Ahvaz than Tehran while Tehran was more pollutant in terms of CO and SO(2). Diurnal variations of O(3) in weekend were the only trend located above weekday variations along the daytimes. Hourly variations of all pollutants changed with a wider range of concentrations in Ahvaz. Diurnal peaks of all pollutants showed their highest level on Monday as the busiest day in mega city, Tehran with the exception of SO(2). PM(2.5) was the worst and limiting pollutant for both cities. Accordingly, winter was the most polluted season by 77 and 33 μg m(−3) in Ahvaz and Tehran, respectively. Number of clean days was significantly lower in Ahvaz (no-day) than mega city, Tehran (186 days). Although, annual PM(2.5) concentrations were more in Ahvaz, the higher at-risk population in Tehran caused more health endpoints in the capital of Iran. Consequently, both cities should have their own especial pattern to control air pollution and attributed health damages.

BACKGROUND AND PURPOSE: The Karoon River, located in southwest Iran, has always been considered as an important water source for people in the southward areas. Khuzestan Province is one of the strategic provinces of Iran thus the development of this province is significantly affected by the water pollution of the Karoon River system. Therefore, the current study aims to assess the environmental vulnerability of the Karoon River as well as preparing a classified map of its vulnerabilities using the fuzzy logic method via the geographical information systems (GIS). METHODS: In this study, the required data were gathered from the Water and Electricity Organization of Khuzestan Province. Afterward, the primary maps were created by converting the map of the study origin into a raster format. Then, fuzzy membership was performed by placing the digits in the range of zero and one using the fuzzy membership function. The primary maps were mixed, and finally, the risk map was prepared by applying the fuzzy overly function. RESULTS: According to the results, a clear trend of water quality deterioration exists since water moves from upstream to downstream areas. The ecological vulnerability of the Karoon basin is mostly located at a low-level (78.05 %) rank. The vulnerable areas were ranked extremely high, high, medium, and low as 2.09, 8.09, 12.08, and 78.05, respectively. CONCLUSIONS: Considering that 22 % of the Karoon River drainage basin in Khuzestan province is considered to have a medium to extremely high risk range, it is mandatory for the authorities to take precautions to prevent the entry of polluting sources into this precious river.

A photocatalytic sulfate radical-based advanced oxidation process was studied to degrade 4-chlorophenol (4-CP) using persulfate (PS) catalyzing UV light and heterogeneous catalyst. In this regards, ferroferric oxide nanoparticles anchored on activated carbon (FOC) was applied as a supporter of TiO2 nanoparticles for fabricating of a recoverable photocatalyst (FOCT). Some analysis techniques including PL, UV–vis DRS, XRD, FESEM-EDS, BET, TEM and VSM were utilized to determine the optical, structural, textural and physicochemical characteristics of FOCT. The reaction mechanisms of PS activation and the generation of free radicals were described in details. Moreover, degradation intermediate products were identified and reaction pathway were proposed. It was found that photocatalytic activity and oxidation performance of pure TiO2 were improved after decoration on FOC. An excellent elimination efficiency was achieved in coupling of FOCT and UV irradiation with PS. Over 99 % of 4-CP (60 mg/L) and 49 % of TOC were removed by FOCT/UV/PS at optimum operational conditions. Furthermore, high PCP decontamination rate (> 86 %) was obtained, even at high concentrations (100 mg/L). During consecutive five runs of catalyst use, the degradation rate was decreased slightly to 88 % with a negligible decline in Fe and Ti leaching, demonstrating the excellent reusability and durability of FOCT in oxidation process. SO4 – and HO radicals were detected as main reactive species that involved in the degradation of 4-CP over FOCT/UV/PS system. Thanks to good performance and easy recovery of catalyst, FOCT/UV/PS hybrid system has a great potential for environmental remediation perspectives.

This study reports temporal and spatial variations of 16 different species of particulate polycyclic aromatic hydrocarbons (particle-bonded PAHs) in the indoor and outdoor environments of three sampling sites in Bandar Mahshahr city, Iran. A low-volume air sampler was employed to collect size-segregated particulate matter during winter (October to December 2015), and summer (July to September 2016). The results showed that the annual concentrations of indoor and outdoor PM10 and PM2.5 were much higher than the related World Health Organization guidelines. The concentration of total particle-bonded PAHs (TPAHs) was higher in winter than in summer and a significant difference between the two sampling seasons was observed. The indoor and outdoor carcinogenic PAHs to TPAHs concentrations ratios in the sampling sites in summer and winter were as follow: for PM10 40.15-42.51%, PM2.5 41.30-42.97%, and PM1 43.07-44.36%, respectively; furthermore, the smaller the particle size, the higher the percentage of carcinogenic PAHs. 2 ring PAHs had a very small contribution to the total PAHs (about 1%), whereas PAHs with 3-to-4 rings had much larger contributions, ranging from 71.65% to 75.17%. The results demonstrated that as PM size decreased, the proportion of 5-to-6-ring PAHs to the total PAHs increased. Since 5-to-6- ring PAHs are considered to be more toxic, hence more attention should be paid to fine particles. The diagnostic ratios of indoor and outdoor of three sampling sites in both seasons suggested that petrogenic sources, as well as combustion of petroleum and other fossil fuels were the main PAHs sources.

This study investigates the concentrations of PM10-bound PAHs and their seasonal variations in three cities of Ahvaz, Abadan, and Asaluyeh in Iran. The mean concentrations of PM10 in two warm and cold seasons in Ahvaz were higher and in Abadan and Assaluyeh were lower than the national standard of Iran and the guidelines of the World Health Organization. The Σ16 PAHs concentration in ambient air PM10 during the cold season in Ahvaz, Abadan and Asaluyeh was 244.6, 633, and 909 ng m− 3, respectively, and during the warm season in Ahvaz, Abadan, and Asaluyeh was 242.1, 1570 and 251 ng m− 3, respectively. The high molecular weight PAHs were the most predominant components. The most abundant PAHs species were Pyr, Chr, B [ghi] P, and Flt. The results showed that the total PAHs concentration in the cold and warm seasons was dependent on industrial activities, particularly the neighboring petrochemical units of the city, vehicular exhausts, traffic and use of oil, gas, and coal in energy production. The total cancer risk values as a result of exposure to PAHs in ambient air PM10 in all three cities for children and adults and in both cold and warm seasons were between 1 × 10− 6 and 1 × 10− 4, and this indicates a potential carcinogenic risk. Therefore, considering the various sources of air pollutants and its role on people’s health, decision makers should adopt appropriate policies on air quality to reduce the ambient air PAHs and to mitigate human exposure.

Ag2O/GO/TiO2 composite nanoparticles were synthesized via a two-stage route including wet chemical and sol-gel techniques. The phase regarding the composition and morphology of composite nanoparticles was characterized using X-ray diffraction (XRD), Fourier transfer infrared (FT-IR) spectroscopy, and field emission scanning electron microscopy (FESEM). The structural studies revealed the successful formation of 300-nm Ag2O/GO/TiO2 composite spheres self-assembled to 35-nm particle aggregates. UV-Vis diffuse reflectance spectroscopy (DRS) was utilized to investigate optical properties. The results indicated an absorption edge in the UV region with a band-gap equivalent to 3.2 eV for Ag2O/GO/TiO2 composite nanoparticles. The morphological features of the sample were investigated with a Zeiss (EM10C, Germany) transmission electron microscope (TEM) operating at 100 kV.

Characteristics, sources and health risks of atmospheric PM10-bound polycyclic aromatic hydrocarbons (PAHs) on residents living in different regions of Ahvaz, Southwest Iran were investigated during 2016-2017. 84 samples were taken from the different regions: (S1) industrial; (S2) high traffic and (S3) residential sites in Ahvaz metropolitan. Urinary samples were collected from people who came to the east health center of Ahvaz. Urinary 1-hydroxypyrene and PAHs levels were analyzed by Gas Chromatography with Mass Spectrometry (GC/MS). Exposure and risk assessment (Incremental Lifetime Cancer Risk (ILCR), Lifetime Average Daily Dose (LADD) and hazard index (HI)) of these pollutants were estimated, using USEPA's exposure parameters. Results of this study showed that in the air of residential and industrial areas observed the lowest and the highest level of PAHs, respectively. High molecular weight compounds (2-4rings), contributed to 85 of n-ary sumation PAHs mass in the atmospheric PM10-bound samples. Industrial processing and petroleum refining, were identified to be major outdoor resources of PAHs. Based on the result of this study, the highest and the lowest concentration of PAHs metabolites were observed in the industrial and residential areas. Average urinary 1-hydroxypyrene levels of S1, S2 and S3 regions were 0.4735; 1.311 and 1.4942 ng/dL, respectively. The values of ILCR in cold (0.06913) and warm (0.052854) seasons were higher than EPA which, was significantly correlated with the concentration of PAHs. In conclusion, increasing exposure concentration of polycyclic aromatic hydrocarbons would have a significant potential for increased ILCR and risk of health endpoint. ILCR in different areas was significantly higher than standard. Our results show that the air quality of Ahvaz city was in an unfavorable condition and increasing exposure concentration of PAHs would have a significant potential for increased ILCR and risk of diseases.

Background: Antibiotics are considered important and integral parts of modern life, and are widely used for treating human and animal illnesses, in medicine and veterinary medicine. However, they can cause environmental pollution and may lead to increased bacterial resistance even at low concentrations. Methods: In this study, Ampicillin degradation from β-lactam antibiotic family was studied, using a surface methodology consisting of ultraviolet radiation (254 nm) and H2O2 oxidation process in an 8-watt Pyrex reactor. The variables used included the reaction time (30-60 min), Ampicillin concentration (5-25 mg/l), H2O2 concentration (5-25 mg/l), and pH range of 3-9 at three alpha levels of -1, 0 and +1. Results: The data were analyzed by the analysis of variance test (ANOVA), while the validity was evaluated using regression coefficients. The optimum condition for Ampicillin degradation followed a linear model, at a 60-min. reaction time and pH 3, the Ampicillin (5mg/l) and hydrogen peroxide (25mg/l) provided the maximum antibiotic removal efficiency (82%). Conclusions: The results suggest a positive and significant effect for the antibiotic concentration and a negative effect for the pH. The Ampicillin concentration with a coefficient of 8.91 had the highest impact on the efficiency of the removal process. Therefore, antibiotic pollution in the environment can be reduced through the UV-H2O2 process, so as to protect human health from the associated hazards.

Since late 2019 many people all over the world have become infected and have died due to coronavirus. There have been many general studies about the spread of the virus. In this study, new and accumulated confirmed cases (NCC and ACC), new and accumulated recovered cases (NRC and ARC), and new and accumulated deaths (ND and AD) were evaluated by geographical properties, meteorological parameters and air particulate matters between 3 April 2020 and 11 June 2020 within 15 provinces in Iran. Meteorological parameters, air particulate matters and COVID-19 data were collected from Iran Meteorological Organization, the Environmental Protection Agency and Aftabnews website, respectively. The results of the study show that provinces in dry lands (i.e., Kerman and South Khorasan) not only had low admission of NCC, ACC, ARC and AD but also presented lower rates of NCC, ACC and AD per 105 population. Air temperature showed positive and significant correlation with the number of COVID-19 cases. This is because of hot outdoor air especially in costal and equatorial regions that forces people to stay in closed environments with no ventilation and with closed-cycle air conditioners. Maximum air pressure was found to be the most frequent (66%) and significant parameter correlating with health outcomes associated with COVID-19. The most engaged province in this study was Khuzestan, while provinces in dry lands (i.e., Kerman and South Khorasan) showed low number of health endpoints associated with COVID-19. The highest rate of accumulated and new recovered cases per 105 population were also found in Khuzestan and Kerman provinces. North Khorasan also showed the worst rate of N&ARC/105 population. Therefore, air temperature, dry lands and population were the most important factors for the control of coronavirus spread.

Air pollution is one of the most pressing issues in populated Middle Eastern cities, in particular for the city of Ahvaz, Iran, imposing deleterious effects on the environment, public health, economy, culture, and other sectors. In this study, we investigate the relationship between meteorological parameters, PM(10), AOD, air mass source origin, and visibility during severe desert dust storms (Average(3h) PM(10) > 3200 µg m(−3)) between 2009 and 2012. Six of seven such events occurred between February and March. Interestingly, for the seven cases there was always an alarming PM(10) mass concentration peak (137–553 µg m(−3)) between 12:00–18:00 (local time) that was 18–24 h before the dominant peak of the storm (3279–4899 µg m(−3)). The maximum wind speed over the multi-day periods examined for the dust storms is usually observed 6 h before the alarming PM(10) peak. The minimum relative humidity, dew point temperature and air pressure occurred ± 3 h around the time of the alarming PM(10) peak. Wind speed was the meteorological parameter that was consistently higher around the time of the first peak as compared to the second peak, with the reverse being true for sea level pressure. Based on four years of daily data in Ahvaz, PM(10) was positively correlated with wind speed and air temperature and inversely correlated with sea level pressure and RH. An empirically-derived equation with R(2) = 0.95 is reported to estimate the maximum PM(10) concentration for severe desert dust events in the study region based on meteorological parameters. Finally, AOD is shown to correlate strongly (R(2) = 0.86) with PM(10) during periods with severe desert dust storms in the region.

Background: Trihalomethanes (THMs) are the first disinfectant by-products in the drinking water distribution network and classified as potential carcinogens. The presence of THMs in chlorinated water depends on the pH, water temperature, contact time between water and chlorine, type and dose of disinfection, bromide ion concentration, and type and concentration of natural organic materials (NOMs). In the present study, the formation of THMs was evaluated by water quality parameters and modeled by an artificial neural network (ANN) approach through five water distribution networks (WDNs) and Karoun river in Khuzestan province.Results: This study was conducted from October 2014 to September 2015. Results showed that THMs concentration ranged in five WDNs, including Shoushtar, Ahvaz 2, Ahvaz 3, Mahshahr, Khorramshahr, and Karoun river through N.D.-9.39 µg/L, 7.12-28.60, 38.16- 67.00, 17.15-90.46, 15.14-29.99 and N.D.-156, respectively.Conclusions: The concentration of THMs exceeded Iran and EPA standards in many cases in Mahshahr and Khorramshahr WDNs. Evaluation of R2, MSE, and RMSE showed the appropriate correlation between measured and modeled THMs, indicating good ANN potential for estimating THM formation in water sources.

Heavy metals are kind of toxic substances which are abundant in all municipal, agricultural, industrial and treated wastewaters. In this research, a comparative study was carried out for adsorptive removal of Cd2+ from aqueous solution using raw oak waste and NaOH-activated oak waste at different experimental conditions namely, pH of solution (2–8), contact time (5–240 min), adsorbent dosages (0.1–10 g/L) and initial Cd2+ concentrations (25–100 mg/L). In addition, the experimental data of Cd2+ adsorption were fitted with different isotherm and kinetic models to determine the most appropriate model. Artificial neural network (ANN) model was also used to find the effect of each individual parameter on Cd2+ adsorptive removal. Based on the results of batch experiments, adsorbent dosages and initial Cd2+ concentrations had direct and indirect relationships with Cd2+ removal, respectively. Furthermore, among all applied isotherm and kinetic models, Langmuir isotherm model and Avrami fractional-order kinetic models could best-fitted with the experimental data of Cd2+ removal. The results of thermodynamic studies revealed that the adsorption of Cd2+ onto the surfaces of oak waste adsorbents is exothermic and spontaneous. Finally, according to the findings of ANN studies, this approach could model the role of each parameter on Cd2+ removal with high coefficient of correlation (>0.99). Accordingly, pH of solution and temperature had the highest and lowest influence on removal of Cd2+ from solution, respectively. The results implied that oak waste can be selected as a promising and environmentally friendly adsorbent for the effective remediation of water bodies containing heavy metals.

A disastrous outbreak of thunderstorm-induced asthma attacks posed a major public health threat in Ahvaz, Iran in autumn of 2013 (>15,000 referrals to hospital emergency rooms and pulmonary clinics). City officials claimed that promoting factors included acid rain, particulate matter, ozone, and polycyclic aromatic hydrocarbon compounds (PAHS) could lead to this phenomenon. After these potential causes were rejected by careful research, the next possible cause that this study addresses is a potential link of the asthma attacks to airborne pollen grains and fungal spores. In order to sample these parameters, a Hirst-type volumetric spore sampler was used, which was installed on the rooftop of the sampling site. Sampling was done during two six-month periods to characterize the regional bioaerosol. The first period included the autumn (September 22 to December 20 of 2016) and winter seasons (December 21 of 2016 to March 19 of 2017), while the second period included the following autumn (September 23 to December 21 of 2017) and winter seasons (December 22 of 2017 to March 20 of 2018). In both studied periods, airborne weed pollen grains, especially Amaranthaceae sp., were by far the greatest contributor to total airborne pollen grain concentrations (50.45%, 3757 pollen grains/m3 and 52.12%, 2392 pollen grains/m3, respectively). Among fungal spores, Cladosporium had the highest concentrations (75.29%, 258677 spores/m3 and 80.33%, 247693 spores/m3, respectively). Findings also showed that concentrations of airborne pollen grains were higher in autumn seasons (6361 and 4167 pollen grains/m3, respectively) in comparison with winter seasons (1085 and 423 pollen grains/m3, respectively), while the concentrations of fungal spores were enhanced in winter seasons (189216 and 160962 spores/m3, respectively) versus autumn seasons (154377 and 147377 spores/m3, respectively). Fungal spores exhibited a uniform distribution during the entire study period, but airborne pollen grains were significantly higher in autumn seasons. The numbers of referrals associated with thunderstorm asthma attacks decreased drastically after implementing Conocarpus erectus tree pruning activities. We concluded that the autumnal thunderstorm asthma attacks in Ahvaz might be triggered by a combination of bio-allergens (fungal spores and airborne pollen grains such as from Conocarpus erectus) and high levels of air pollutants from industrial activity. The results of this work suggest controlling bio-allergen levels by preventive measures such as tree pruning, weed removal, and emasculating urban green infrastructures before the flowering season.

This study was to investigate the Sonoelectro-activated persulfate oxidation process for petrochemical wastewater treatment. The effects of Sonoelectro-activated persulfate, electro-activated persulfate, Sono-activated persulfate, persulfate, and ultrasound processes for COD removal were determined. The results reveal that the maximum removal efficiency was obtained at pH = 3, ultrasonic power of 300 W, ultrasonic frequency of 130 kHz, potential electrode of 10 V and persulfate concentration of 20 mM. It was observed that the effective removal of COD was 82.31% for the combined system (Sonoelectro-persulfate), 68.97% for electro-persulfate, 21.11% for Sono-persulfate, 13.06% for persulfate and 2.6% for the single ultrasound system, respectively. The highest removal efficiency obtained at 333 K that was 91.2% after 120 min. In addition, the reaction kinetics of COD removal through Sonoelectro-persulfate process fitted well for pseudo-second-order kinetic model with the regression coefficient of 0.89. According to the results, Sonoelectro-activated persulfate oxidation process has been considered as an effective and efficient technique for petrochemical wastewater treatment.

In this study, optimization of adsorptive removal of two cationic (methylene blue (MB)) and anionic (acid red 73 (AR 73)) dyes with modified oak waste (MOW) adsorbent was carried out using response surface methodology (RSM). The input variables included initial solution pH (2–10), contact time (20–200 min), adsorbent dosage (0.5–2.5 g/L) and initial dyes concentrations (10–90 mg/L). Furthermore, the surfaces of the adsorbent were modified with different modifiers to find the most efficient adsorbent. The obtained results of comparative studies on dyes adsorption confirm that sodium hydroxide, compared to other modifiers, has the highest ability to activate the surfaces of the oak waste (OW) to remove dyes from the solution. Using NaOH, the removal efficiency of MB and that of AR 73 were obtained to be 96% and 29%, respectively. In addition, results of the optimization study showed that RSM could significantly predict the experimental data of dyes removal with a high correlation coefficient (0.991 for MB and 0.993 for AR 73). The optimum experimental conditions for dyes removal were pH of 6.2, 160 min contact time, 2.0 g/L adsorbent dosage and 70 mg/L initial dye concentrations. Under this condition, the removal efficiency for MB and AR 73 reached 85.36% and 41.27%, respectively. Ultimately, from the findings of this study, it is observed that MOW can be used as an efficient and cost-effective adsorbent for the removal of dyes from the contaminated aqueous solution.

The improper use of antibiotics and their discharge into the environment can have serious and hazardous consequences. The purpose of this research is to synthesize an activated carbon impregnated magnetite composite (PAC/Fe), prepare PAC/Fe/Ag/Zn nanocomposites, and innovate by simultaneously synthesizing two metals, zinc and silver, on magnetically activated carbon and check its ability to remove azithromycin antibiotic (AZT) from an aqueous solution via UV system. PAC/Fe/Ag/Zn nanocomposites were characterized by various techniques including XRD, FESEM, and EDX. A series of batch experiments were carried out under various experimental conditions such as pH of the solution (3-11), contact time (0-120 min), initial concentration of AZT (10-40 ppm), amount of PAC/Fe/Ag/Zn nano-absorbent (0.01-0.04 g/l), and recoverability and reuse. Some common isotherm models were used for the study of AZT adsorption removal and finding the best model. Also, kinetic studies of AZT removal were performed by fitting the experimental data on first-order and second-order models. In this system, under optimal conditions of pH = 9, 120 min with 0.04 g/l of PAC/Fe/Ag/Zn, 99.5% of 10 ppm AZT were degraded under UV-C irradiation. Furthermore, the obtained results of isotherm and kinetic studies revealed that Langmuir (R

Total petroleum hydrocarbons (TPHs) are common environmental pollutants in aquatic ecosystems that tend to adsorb onto the sediments. This study aimed to monitor the concentration and assessment of contamination level of TPHs in the sediments of Karun River and Bahmanshir estuary, which will eventually flow into the Persian Gulf. GIS-mapping technique was used to indicate the distribution of TPHs. The samples were collected during dry and wet seasons at 15 monitoring stations. - The maximum amount of TPHs was obtained at station No. 14 in the dry season (225.29 μg/g). The indices of determining the pollution source showed that hydrocarbons in polluted areas were mainly of biogenic origin. Compared to sediment quality guidelines (SQGs) and contamination factor (Cf), the study area sediments were in the conditions of moderate pollution and had a low ecological risk.

This study reports temporal and spatial variations of 16 different species of particulate polycyclic aromatic hydrocarbons (particle-bonded PAHs) in the indoor and outdoor environments of three sampling sites in Bandar Mahshahr city, Iran. A low-volume air sampler was employed to collect size-segregated particulate matter during winter (October to December 2015), and summer (July to September 2016). The results showed that the annual concentrations of indoor and outdoor PM(10) and PM(2.5) were much higher than the related World Health Organization guidelines. The concentration of total particle-bonded PAHs (TPAHs) was higher in winter than in summer and a significant difference between the two sampling seasons was observed. The indoor and outdoor carcinogenic PAHs to TPAHs concentrations ratios in the sampling sites in summer and winter were as follow: for PM(10) 40.15–42.51%, PM(2.5) 41.30–42.97%, and PM(1) 43.07–44.36%, respectively; furthermore, the smaller the particle size, the higher the percentage of carcinogenic PAHs. 2 ring PAHs had a very small contribution to the total PAHs (about 1%), whereas PAHs with 3-to-4 rings had much larger contributions, ranging from 71.65% to 75.17%. The results demonstrated that as PM size decreased, the proportion of 5-to-6-ring PAHs to the total PAHs increased. Since 5-to-6- ring PAHs are considered to be more toxic, hence more attention should be paid to fine particles. The diagnostic ratios of indoor and outdoor of three sampling sites in both seasons suggested that petrogenic sources, as well as combustion of petroleum and other fossil fuels were the main PAHs sources.

Wastewater treatment plant (WWTP) is one of the significant sources of Microplastics (MPs) release to the environment. Di 2-ethyl hexyl phthalate (DEHP) is used as an additive for more flexibility of plastics. In this study, we determined the number, size, shape, and color distribution of MPs as well as the concentration of DEHP in MPs and wastewater during the wastewater treatment process in WWTP. Samples were collected from 4 stations of different treatment stages of WWTP. The microplastic particles and the concentration of DEHP were detected via the fluorescence and polarized light microscopy and GC/MS instrument, respectively. The number of MPs decreased from 9.2 (station 1) to 0.84 MP/L (the final treated effluent) during the wastewater treatment process. Also, the size of MPs at the last station was smaller than the other stations. The mean concentrations of DEHP in MPs in stations 1, 2, 3 and 4 had the respective values of 83.3, 61.05, 30.62 and 17.49 μg/g, while the mean concentrations of DEHP in wastewater in stations 1, 2, 3 and 4 were 30.08, 25.07, 9.56, and 8.13 μg/L, respectively. This study shows that despite the removal of high amounts of MPs and DEHP in the final effluent of WWTP, due to the high volume of this effluent (2.828 × 108 L/d), significant amount of MPs (2.419 × 107 MP/day) and DEHP enter the aquatic environment daily, which may threaten the health of the fish and aquatic organisms and ultimately on the health of the local population.

This study investigates the concentrations of PM(10)-bound PAHs and their seasonal variations in three cities of Ahvaz, Abadan, and Asaluyeh in Iran. The mean concentrations of PM(10) in two warm and cold seasons in Ahvaz were higher and in Abadan and Assaluyeh were lower than the national standard of Iran and the guidelines of the World Health Organization. The Σ16 PAHs concentration in ambient air PM(10) during the cold season in Ahvaz, Abadan and Asaluyeh was 244.6, 633, and 909 ng m(− 3), respectively, and during the warm season in Ahvaz, Abadan, and Asaluyeh was 242.1, 1570 and 251 ng m(− 3), respectively. The high molecular weight PAHs were the most predominant components. The most abundant PAHs species were Pyr, Chr, B [ghi] P, and Flt. The results showed that the total PAHs concentration in the cold and warm seasons was dependent on industrial activities, particularly the neighboring petrochemical units of the city, vehicular exhausts, traffic and use of oil, gas, and coal in energy production. The total cancer risk values as a result of exposure to PAHs in ambient air PM(10) in all three cities for children and adults and in both cold and warm seasons were between 1 × 10(− 6) and 1 × 10(− 4), and this indicates a potential carcinogenic risk. Therefore, considering the various sources of air pollutants and its role on people’s health, decision makers should adopt appropriate policies on air quality to reduce the ambient air PAHs and to mitigate human exposure.

The aim of this study was to determine the correlation between PM2.5 and NO2 pollutants and oxidative stress marker (8-isoprostane) and lung function tests (FVC and FEV1) in healthy children who were living and studying in three different areas of Ahvaz city including A1: Naderi site with high traffic, A2: Alavi Alley site with average traffic, and A3: Ein 2 site with low traffic (a rural area on the suburb of Ahvaz). 30 students in the 12–13 year-old range were selected from each studied zone (1, 2 and 3 sites) during three months of year. Of each student, one sample was taken every two weeks to measure 8-isoprostane of exhaled breath condensate (EBC). Air pollution data were collected from three air quality monitoring stations. Also, the relationship between air pollution and 8-isoprostane as well as lung function tests were determined using generalized estimating equations (GEE). The mean concentration of PM2.5 and NO2 in A1, A2 and A3 areas were 116, 92 and 45 (μg/m3) also 77, 53 and 14 (ppb) respectively. Among all studied students, there was a significant correlation between the increase of mean concentration of PM2.5 and NO2 in 1–4 before sampling day, increased 8-isoprostane concentration and decreased FEV1, while there was no significant correlation between them and decreased FVC. In A1 site, an increase in IQR (13 μg/m3) PM2.5 and IQR (6.5 ppb) NO2 on 1–4 days before sampling was associated with 0.38 unit (95% CI: 0.11, 0.65) and 1.1 unit (95% CI: 0.85, 1.35) increase in 8-isoprostane concentration, also decreased 121 ml and 190 ml FEV1, respectively. Results showed that the short-term exposure to traffic-related air pollution can decrease the values of lung function indices and increase the oxidative stress. It may adversely affect children’s lungs. Keywords: Air pollution, Lung function, 8-Isoprostane, Traffic, Ahvaz, Iran

Antibiotics have caused major concerns in environmental control due to the cumulative adverse effects on human health. This study investigates the effect of four variables: pH (3, 6, and 9), azithr...

Background & Aims of the Study: Discharge of untreated colored wastewater into aquatic environments could cause problems such as cancer. Among the various treatment methods, advanced oxidation processes (AOPs) have attracted much attention in recent years. The aim of this study was the removal of acid orange 7 dye using CoFe2O4@PAC nanocomposite in the presence of peroxymonosulfate (PMS) and hydrogen peroxide (H2O2). Materials & Methods: The various variables effect including pH, catalyst dose, peroxymonosulfate and hydrogen peroxide concentration, reaction time, and initial dye concentration were evaluated. The synthesized nanocomposite was characterized by SEM, EDX, XRD and BET analyses. The residual concentration of AO7 dye was determined using UV–Vis spectrophotometer at wavelength of 485 nm. Results: It was found that decolorization increases by increasing the catalyst dosage and reaction time, and decreasing pH. With increasing the dye initial concentration from 10 mg/L to 250 mg/L, in the presence of H2O2 and PMS dye removal decreased from 99.5% to 39.7% and from 99.9% to 43.7%, respectively. The adsorption kinetics was found to follow pseudo-first-order kinetic model (R2>0.99). Conclusions: The results indicated that the prepared composite could be used as an effective and environmental friendly magnetic adsorbent for the removal of AO7 dye from aqueous solutions.

Background Few studies have examined nano-sized plastic particulates (NPs) exposure in relation to oxidative stress and biochemical responses in rodents, commonly used for toxicity evaluations on which to base risk assessment for humans.Methods Here we explored possible oxidative stress and biochemical responses of five weeks oral exposure to polystyrene (PS) nanoparticles (1, 3, 6 and 10 mg/kg body weight per day) in male rats. We used variance analysis and variance explained statistic eta-squared (𝜂2) to estimate the strength of relationships worked out. The whole body scanning further provided insight into the bio-distribution of nanoplastics upon oral exposure.Results Results demonstrated the accumulation of PS-NPs through whole body and also a dose-dependent increase in the production of reactive oxygen species (ROS). Significant alterations in antioxidant responses including serum levels of catalase, superoxide dismutase (SOD), and total glutathione content were noticed, pointing towards a perturbation of redox state induced by the exposure conditions. Acetylcholinesterase level in highest dose group was about 40 percent lower than those in control group. Biochemical parameters viz. glucose, cortisol, lipase, lactate, lactate dehydrogenase (LDH), alkaline phosphatase, gamma-glutamyl transpeptidase (GGT), triglycerides, and urea showed a significant increase, while total protein, albumin and globulin levels showed an appreciable decline.Conclusion The pattern of associations noticed with AChE activity and biochemical responses in our study suggests the possibility that a neurobehavioral effect or dysfunctions in energy metabolism, or both, may be the potential mode of action, possibly through stress response as well as liver function. Perturbations of creatinine and uric acid levels are indeed plausible biological explanations for the association with kidney dysfunction. Although we provided a new scientific clue for exploring the biological effects of plastics nanoparticles, the results warrant additional research with a larger sample size. The suggested potential mechanisms also remains to be investigated.

Furfural is an organic matter which is commonly used in solid resin plastic production and paper manufacturing. In this study, the removal of furfural was carried out using oxalate (OX) and activated persulfate (PS) with Fe(III). The effect of pH, Fe(III) dosage, OX ion dosage, species radicals, the molar ratio of citric acid, coexisting substances, environmental applications, reaction mechanisms, and intermediates compound on the removal of furfural were investigated. In addition, artificial neural network (ANN) model was designed to determine the optimum value and importance of the effective variables to attain the higher efficiency. This study indicates the application of ANN for prediction of performances in competitive advance oxidation process. Intermediate compounds were identified, including ferulic acid –CO2, 2-furfural, oxime-, methoxy-phenyl, 2,2′-bifuran, and cyclohexasiloxane. The higher degradation efficiency was 85.8%, which was obtained at furfural 40 mg/L, Fe 0.002 g, PS 0.05 g, pH 4, and the molar ratio of citric acid: 1:1. Comparison between the photodegradation efficiency of experimental results and the predicted results of the designed ANN models showed that both processes have almost equal efficiency.

This study aimed to survey the concentration of PM10 and heavy metals (cadmium, chromium, cobalt, nickel, lead, and zinc) on normal and dusty days in Ahvaz, Iran. Concentrations of PM10 in a high-traffic area of the city were measured from October 2012 to September 2013 using a high-volume sampler (HVS). Extracted heavy metals were speciated and quantified using Inductivity Coupled Plasma Optical Emission Spectrometry (ICP-OES). The results of this study showed that the average concentration of PM10 in the autumn (October, November, and December), winter (January, February, and March), spring (April, May, and June), and summer (July, August, and September) was 131, 189, 145, and 127 µg/m3 on normal days, respectively. The corresponding values on dusty days were 410, 742, 300, and 278 µg/m3, respectively. The concentrations of the heavy metals during dusty days were higher than those on normal days. The ratio of the overall mean concentration of the heavy metals on dust storm days relative to normal days (D/N ratio) ranged from 1.21 to 2.53. Due to the importance and impacts of PM10 and associated heavy metals on human health, further studies should be conducted to evaluate the concentrations, impacts, and the associated diseases during pollution periods to establish and implement strategies to minimize harmful effects of PM inhalation.