Spatial distribution, sources identification, and health risk assessment polycyclic aromatic hydrocarbon compounds and polychlorinated biphenyl compounds in total suspended particulates (TSP) in the air of South Pars Industrial region-Iran.

South Pars Industrial Energy Zone, located in the southwest of Iran along the Persian Gulf coast, encompasses many industrial units in the vicinity of urban areas. This research study investigated the effects of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) on human health and the environment. Suspended particulate matters (SPM) in the air sampled, in summer and winter 2019, from ten stations next to industrial units and residential areas. The samples were analyzed by gas chromatography-mass spectrometry (GC-MS). Spatial distribution maps of pollutants in the region were prepared using GIS software. The highest carcinogenic risk due to PAHs and PCBs measured as ([Formula: see text]) and ([Formula: see text], respectively. According to the US Environmental Protection Agency limit ([Formula: see text]), the cancer risks from PAH compounds were significant and need further investigation. The PCB cancer risks were within acceptable ranges. The highest adsorption ratios for PAHs were obtained through skin and PCBs by ingestion. The maximum measured non-carcinogenic hazard indexes (HI) turned out to be 0.037 and 0.023 for PAH and PCB, respectively, and were reported as acceptable risks. The predominant source of PAH in industrial areas was liquid fossil combustion, and in urban areas replaced by coal-wood-sugarcane combustion. Petrochemical complexes, flares, power plants (69%), electric waste disposal sites, and commercial pigments (31%) were reported as PCB sources. Industries activities were the most effective factors in producing the highest level of carcinogenic compounds in the region, and it is necessary to include essential measures in the reform programs.

Occurrence and spatial distribution of microplastics in sediment and fish along the Persian Gulf-a case study: Bushehr Province, Iran.

Microplastics (MPs) contamination in the marine environment is a global threat. The present study is the first to comprehensively investigate the MPs contamination in the marine environment in Bushehr province along the Persian Gulf. For this purpose, 16 stations were selected along the coast and 10 fish samples were collected. The results obtained from MPs in sediment samples indicate the mean abundance of MPs in different sediment samples was 57.19 Particles/Kg. The dominant MPs color in sediment samples was black, accounting for 47.54%, followed by white (36.07%). As for MPs in fish, the highest MPs digested in different fish samples were 9. In addition, over 83.3% of MPs observed in fishes were black followed by red and blue (6.67%). Overall, the presence of MPs in fish and sediment can be attributed to improper disposal of industrial effluents; an efficient measurement is required in order to improve the quality of the marine environment.

Distributing and assessing fluoride health risk in urban drinking water resources in Fars Province, Iran, using the geographical information system.

Excessive fluoride intake has been reported in many studies, which can lead to diseases such as autism, mental retardation, low birth weight, reproductive disorder, as well as dental and bone fluorosis. The potential risk assessment of fluoride intake for the health of people living in Fars Province, Iran, is investigated. Hence, 1700 drinking water samples were taken from April 2018 to March 2020 in four seasons in 29 cities of Fars Province and were analyzed. Non-carcinogenic health risks of exposure to fluoride through drinking water were evaluated. Moreover, the spatial distribution maps of fluoride and hazard quotient (HQ) risk index were prepared using GIS software. The results showed that the concentration of fluoride in the drinking water of the studied area was in the range of 0.086 to 2.61 mg/L. Accordingly, in 48.27% of the cities, fluoride was in the range below the national and international standards, 34.48% of the cities were in the permissible range of 0.5 to 1.5 mg/L, and 17.24% of the urban areas of the province had fluoride contents above the permissible range. Hazard quotient index had the health risk of HQ > 1 in 27.58% of children, 17.24% of teenagers, and 10.34% of adults in the urban areas of Fars Province. In the cities with HQ > 1, there was risk of diseases associated with excessive fluoride intake. Therefore, it is necessary to replace water supply sources in these cities.

Spatial distribution of BTEX emission and health risk assessment in the ambient air of pars special economic energy zone (PSEEZ) using passive sampling.

Benzene, toluene, ethylbenzene and xylene (BTEX) are a challenging group of volatile organic compounds in industrial and energy areas. Since these aromatics may cause serious diseases such as cancer and respiratory illnesses, they must be monitored. Pars Special Economic Energy Zone (PSEEZ) in Iran is the second largest energy zone of the world with numerous gas refineries and petrochemical complexes for producing a wide range of products. This study is focused on determination of BTEX concentration in the whole South Pars area (46 sampling points) which is the active site of PSEEZ using passive sampling. Then, the results of the passive sampling are used for providing spatial distribution of BTEX using GIS. The annual BTEX measurements revealed that benzene and toluene concentration violates the maximum permitted values at numerous points most of which are located in the vicinity of petrochemical complexes. Active sampling in these complexes not only confirms the results of passive sampling, but also suggests a more intensified BTEX pollution in the air quality of the area which reaches as high as 3500 µg.m-3 and 18,000 µg.m-3 for benzene and toluene, respectively, being far beyond the acceptable standards. Health risk analysis also confirms the intensity of BTEX at the selected points. This study suggests a reconsideration of the location of non-operational sites and personnel who are more vulnerable to BTEX contamination. Also, BTEX profile provided by GIS in this research gives a suitable plan for relocating.

Distribution, source finding, ecological hazard assessment, and water-sediment exchange rate of polychlorinated biphenyl (PCB) congeners in South Pars Industrial Zone, Iran.

South Pars Industrial Zone is located near an Assaluyeh city on the coast of the Persian Gulf and is known as the energy capital of Iran. In this study, environmental and health effects due to PCB congeners had an assessment. In this study, 10 air stations, 10 seawater, and sediments stations were systematically selected and sampled in two seasons. Air, seawater, and sediment pollution made by polychlorinated biphenyls (PCBs) were evaluated. Seawater-sediment exchange conditions using the fugacity coefficient reviewed. PCB levels in marine sediments, seawater, and air based on the analysis of the obtained data were 107.33-172.92 ng/g, ND-135.68 ng/L, and ND-4.4 ng/m3, respectively. The highest concentration was observed in the vicinity of refineries, petrochemicals, and petroleum export facilities. These values had increased significantly compared to values of studies, conducted in similar areas. The sources were electrical wastes, storage sites, power generation units, and wastewater treatment. The ecological risk of seawater was assessed to be low to high, while sediment risks were reported with a low to moderate risk range. In 70% of the stations, the predominant transfer was from sediments to seawater; sediments were in fact the secondary source of seawater pollution. It is suggested for the area to be continuously monitored, while engineering and management measures should be adopted to improve the situation and also prevent the spread of pollution.

Spatial patterns of heavy metals in soil under different geological structures and land uses for assessing metal enrichments.

One hundred and thirty composite soil samples were collected from Hamedan county, Iran to characterize the spatial distribution and trace the sources of heavy metals including As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn, and Fe. The multivariate gap statistical analysis was used; for interrelation of spatial patterns of pollution, the disjunctive kriging and geoenrichment factor (EF(G)) techniques were applied. Heavy metals and soil properties were grouped using agglomerative hierarchical clustering and gap statistic. Principal component analysis was used for identification of the source of metals in a set of data. Geostatistics was used for the geospatial data processing. Based on the comparison between the original data and background values of the ten metals, the disjunctive kriging and EF(G) techniques were used to quantify their geospatial patterns and assess the contamination levels of the heavy metals. The spatial distribution map combined with the statistical analysis showed that the main source of Cr, Co, Ni, Zn, Pb, and V in group A land use (agriculture, rocky, and urban) was geogenic; the origin of As, Cd, and Cu was industrial and agricultural activities (anthropogenic sources). In group B land use (rangeland and orchards), the origin of metals (Cr, Co, Ni, Zn, and V) was mainly controlled by natural factors and As, Cd, Cu, and Pb had been added by organic factors. In group C land use (water), the origin of most heavy metals is natural without anthropogenic sources. The Cd and As pollution was relatively more serious in different land use. The EF(G) technique used confirmed the anthropogenic influence of heavy metal pollution. All metals showed concentrations substantially higher than their background values, suggesting anthropogenic pollution.

Application of pier waste sludge for catalytic activation of proxy-monosulfate and phenol elimination from a petrochemical wastewater.

This investigation aimed to remove phenol from real wastewater (taken from a petrochemical company) by activating peroxy-monosulfate (PMS) using catalysts extracted from pier waste sludge. The physical and chemical properties of the catalyst were evaluated by FE-SEM/EDS, XRD, FTIR, and TGA/DTG tests. The functional groups of O-H, C-H, CO32-, C-H, C-O, N-H, and C-N were identified on the catalyst surface. Also, the crystallinity of the catalyst before and after reaction with petrochemical wastewater was 103.4 nm and 55.8 nm, respectively. Operational parameters of pH (3-9), catalyst dose (0-100 mg/L), phenol concentration (50-250 mg/L), and PMS concentration (0-250 mg/L) were tested to remove phenol. The highest phenol removal rate (94%) was obtained at pH=3, catalyst dose of 80 mg/L, phenol concentration of 50 mg/L, PMS concentration of 150 mg/L, and contact time of 150 min. Phenol decomposition in petrochemical wastewater followed the first-order kinetics (k> 0.008 min-1, R2> 0.94). Changes in pH factor were very effective on phenol removal efficiency, and maximum efficiency (≈83%) was achieved in pH 3. The catalyst stability test was performed for up to five cycles, and phenol removal in the fifth cycle was reduced to 42%. Also, the energy consumption in this study was 77.69 kW h/m3. According to the results, the pier waste sludge catalyst/PMS system is a critical process for eliminating phenol from petrochemical wastewater.

Comparative study of mercury accumulation in two fish species, (Cyprinus carpio and Sander lucioperca) from Anzali and Gomishan wetlands in the southern coast of the Caspian Sea.

Anzali and Gomishan wetlands are considered as two of the most important wetlands in southern coast of Caspian Sea. To investigate mercury accumulation in these ecosystems, total mercury concentrations were measured in the muscle tissue of two fish species. Higher mercury concentrations were detected in C. carpio, an omnivorous benthic/pelagic species (Anzali wetland: 0.2 µg g(-1) wet weight; Gomishan wetland: 0.2 µg g(-1) wet weight), than in S. lucioperca, a carnivorous pelagic species (Anzali: 0.06 µg g(-1) wet weight; Gomishan: 0.15 µg g(-1) wet weight).

Photocatalyst production from wasted sediment and quality improvement with titanium dioxide to remove cephalexin in the presence of hydrogen peroxide and ultrasonic waves: A cost-effective technique.

In this study, wasted sediment (sludge waste from shipping docks) was coupled with titanium isopropoxide by the thermal and sol-gel method as a new photocatalyst. The sediment-titanate catalyst alongside ultrasonic and UV was activated hydrogen peroxide to produce OH radicals and decompose cephalexin (CEP). The photocatalyst was crystalline with 52.29 m2/g BET area. The best destruction rate of 87.01% based on COD test was achieved at optimal conditions (pH: 8, cephalexin concentration: 100 mg/L, H2O2: 1.63 mg/L, UV: 15 W/m2, ultrasonication time: 100 min at 40 kHz, photocatalyst quantity: 1.5 g/L). The trend of anions effect was NO3- ≤ SO42- ≤ Cl-. Decomposition of cephalexin in water solution followed the first-order kinetics (k > 0.01 min-1, R2 > 0.9). The percentage of cephalexin removal from urban water (76%) and hospital wastewater (63%) has decreased compared to the distilled water solution (87%), which is probably due to the presence of radical inhibitors. The consumed electrical energy of the studied system was calculated by 0.031 kW/h. The developed system is a promising and economical method to remove cephalexin.

Phenol removal kinetics from synthetic wastewater by activation of persulfate using a catalyst generated from shipping ports sludge.

Disposal sludges from shipping docks contain elements that have the potential to catalyze the desired treatment process. The current work was designed to decompose phenol from wastewater by activation peroxymonosulfate (PMS) using a catalyst made from sea sediments (at 400 °C for 3 h). The catalyst had a crystalline form and contained metal oxides. The parameters of pH (3-9), catalyst dose (0-80 mg/L), phenol concentration (50-250 mg/L), and PMS dose (0-250 mg/L) were tested to specify the favorable phenol removal. The phenol removal of 99% in the waste sludge catalyst/PMS system was achieved at pH 5, catalyst quantity of 30 mg/L, phenol content of 50 mg/L, PMS dose of 150 mg/L, and reaction time of 150 min. From the results, it was implied that the pH factor was more important in removing phenol with the studied system than other factors. By-products and phenol decomposition pathways were also provided. The results showed that the sea sediment catalyst/PMS system is a vital alternative for removing phenol from wastewater medium.

Magnetic CuNiFe2O4 nanoparticles loaded on multi-walled carbon nanotubes as a novel catalyst for peroxymonosulfate activation and degradation of reactive black 5.

Novel copper-nickel ferrite nanocatalyst loaded on multi-walled carbon nanotube (MWCNTs-CuNiFe2O4) was synthesized and applied to activate peroxymonosulfate (PMS) in the degradation of the reactive black 5 (RB5). The structure of the catalyst was well characterized by scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray powder diffraction (XRD). The MWCNTs-CuNiFe2O4/PMS system showed a high performance in the degradation of RB5 with a kinetic rate of 1.5-2.5 times higher than homogeneous and heterogeneous systems. Maximum degradation efficiency (99.60%) was obtained at an initial pH of 7, catalyst dosage of 250 mg/L, PMS dosage of 4 mM, the temperature of 25 °C, and reaction time of 15 min. Anion experiments emphasized that the presence of nitrate, carbonate, and phosphate in the solution reduced the degradation efficiency by producing reactive species with low oxidation potential. The RB5 degradation rate evolved with temperature, and the activation energy was obtained to be 44.48 kJ/mol. The mechanism of PMS activation and production of free radicals was proposed based on tert-butyl alcohol (TBA), ethanol (EtOH), and potassium iodide (KI) scavengers. Trapping experiments showed that both sulfate (SO4•-) and hydroxyl (•OH) radicals are involved in the catalytic degradation of RB5. The effective treatment of real wastewater and tap water by the MWCNTs-CuNiFe2O4/PMS system requires a long reaction time. Gas chromatography-mass spectrometry (GC-MS) analysis indicated that RB5 can be degraded via methylation, decarboxylation, hydroxylation, and ring/chain cleavage pathways. The stable catalytic activity after three consecutive cycles suggested that MWCNTs-CuFe2O4 is a novel reusability catalyst in PMS activation.

MIL-101(Cr)-cobalt ferrite magnetic nanocomposite: synthesis, characterization and applications for the sonocatalytic degradation of organic dye pollutants.

In this study, for the first time, a novel magnetically recyclable MIL-101(Cr)/CoFe2O4 nanocomposite was prepared via a facile solvothermal method. The morphology, structural, magnetic and optical properties of the nanocomposite were characterized via field emission scanning electron microscopy (FE-SEM), transmission electron microscope (TEM), energy dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), UV-visible spectroscopy (UV-visible) and BET surface area analysis. Furthermore, the sonocatalytic activity of the MIL-101(Cr)-based magnetic nanocomposite was explored for the degradation of organic dye pollutants such as Rhodamine B (RhB) and methyl orange (MO) under ultrasound irradiation in the presence of H2O2. Under optimized conditions, the degradation efficiency reached 96% for RhB and 88% for MO. The sonocatalytic activity of MIL-101(Cr)/CoFe2O4 was almost 12 and 4 times higher than that of the raw MIL-101(Cr) and pure CoFe2O4, respectively. The improved sonocatalytic performance of the as-prepared binary nanocomposite can be attributed to the relatively high specific surface area of MIL-101(Cr) and magnetic property of CoFe2O4, as well as the fast generation and separation of charge carriers (electrons and holes) in MIL-101(Cr) and CoFe2O4. In addition, the trapping tests demonstrated that ·OH radicals are the main active species in the dye degradation process. Moreover, the most influencing factors on the sonocatalytic activity such as the H2O2 amount, initial dye concentration and catalyst dosage were investigated. Finally, the nanocomposite was magnetically separated and reused without any observable change in its structure and performance even after four consecutive runs.

Enhanced fluoride removal over MgFe2O4-chitosan-CaAl nanohybrid: Response surface optimization, kinetic and isotherm study.

In this work an effective adsorption route was developed for fluoride removal from aqueous solution. For this purpose MgFe2O4, MgFe2O4-chitosan and a three component nanocomposite of were synthesized and used. Characterization of the sorbents was performed with FESEM, TEM, FTIR, BET, VSM, SEM mapping and XRD techniques. Effective parameters on the adsorption process such as pH, contact time, adsorbent dosage and fluoride concentration was optimized by response surface methodology (RSM) using Box-Behnken design (BBD). Results showed that solution pH is a significant factor in fluoride adsorption with all adsorbents. However, adsorbent dosage was a significant factor when MgFe2O4-chitosan and three component adsorbents are employed. Kinetic study was performed based on pseudo-first order, pseudo-second order, intraparticle diffusion and Elovich model and results confirmed fluoride adsorption followed the pseudo-second order model. Isotherm study was studied at two concentration ranges of 0.5-10 mg/L and 10-100 mg/L of fluoride ions. Results showed that adsorption process followed Langmuir model with capacity of 263.15 mg/g. Regeneration was performed with NaOH solution (0.1 mol/L). It was found that removal percentage is in the range of 91-73% in five cycles of adsorption and regeneration.