Few plant species used for revegetation grow well in multi-metal-contaminated soils. Vetiver grass (Vetiveria zizanioides) is known to be tolerant of heavy metals. Vetiver has been reported to be effective for revegetation and heavy metal phytoextraction by applying targeted amendments due to its large biomass. In this study, a greenhouse vetiver pot experiment and soil incubation were performed to investigate the growth and Cd, Cr, Cu, Pb, and Zn uptake of vetiver grown in multi-metal-contaminated soils treated with a CaO-activated Si-based slag amendment (0, 0.5, 1.0, and 2.0% w/w). The results showed that the effects of slag amendment on plant growth and heavy metal uptake and distribution were dependent on the amendment dosages and metal species. Although vetiver could grow in contaminated soils, its growth was obviously inhibited. The slag amendment enhanced the vetiver growth and the highest biomass (2.62-fold over the control) was determined at a 1.0% amendment rate. The slag amendment improved plant growth by alleviating the toxicity of heavy metals in plants. This result was mainly attributed to the increases in soil pH and citric acid-extractable Si caused by alkaline amendment. The results suggest that vetiver can be applied to remediate multi-metal-contaminated soils in conjunction with the application of CaO-activated Si-based slag amendment.

The response of antioxidant enzymes to oxidative environmental stress was determined in 5th instar nymphs of Aiolopus thalassinus (Orthoptera: Acrididae) collected from sites with different level of pollution with heavy metals, PO₄³⁻, and SO₄²⁻. The high polluted site induced higher DNA damage to individuals compared to the control site. The highest values of tail length (TL), tail moment (TM), and percent of DNA in tail (TDNA) were found in the gut of 5th instar nymphs from a high polluted site. Also, protein carbonyls and lipid peroxide levels were significantly higher in insects collected from polluted sites compared to those from the control site. A strong positive correlation between both protein carbonyl and lipid peroxide concentration and the pollution level of the sites was found in all tissues of the insects. The activity of superoxide dismutase (SOD) in the brain of insects collected from the high polluted site was significantly higher than that in the thoracic muscles and gut. We observed strong inhibition of catalase (CAT) activity. This effect was apparently caused by pollutants present at the high polluted site. The level of pollution significantly influenced polyphenol oxidase (PPO) activity in A. thalassinus nymphs in all examined tissues. The highest values were observed in the brain. The relationship between pollution and ascorbate peroxidase (APOX) activity in the examined tissues had no clear tendency. However, the lowest APOX activity was observed in individuals from the low polluted site. Level of pollution of sampling sites, oxidative stress biomarkers, and enzymatic response in A. thalanthsis 5th instar were negatively or positively correlated. Oxidative damage parameters, especially the percent of severed cells, lipid peroxides, and the activity of APOX, can be perceived as good markers of environmental multistress.

The effects of slag, fly ash (formed in boiler above 1500 °C), and experimental ash (formed in muffle furnace at 815 °C) on the formation of sulfur trioxide (SO₃) were studied in a fixed bed rector. The results showed that the slag had the best catalytic effect on SO₃ formation, the effect of fly ash was second, and the effect of experimental ash was the worst. The reason may be that the forms of iron in different samples were different. Iron in the experimental ash all existed in the form of Fe₂O₃. Iron in the fly ash mainly existed in the form of composite iron oxides, such as Fe₀.₃Mg₀.₇SiO₃, Ca₃Fe₂(SiO₄)₃, and MgFe₂O₄. Iron in the slag also mainly existed in the form of composite iron oxides, such as CaFe₂O₄, MgFe₂O₄, and CaMgO₀.₈₈Fe₀.₁₂SiO₄. The different forms of iron had different effects on SO₃ formation. Composite iron oxides could produce more oxygen vacancies owing to lattice defects. This likely promoted the migration and regeneration of lattice oxygen and thus better promoted the formation of SO₃ than Fe₂O₃. Moreover, MgFe₂O₄ and Ca₃Fe₂(SiO₄)₃ could better promote SO₃ formation than CaMgO₀.₈₈Fe₀.₁₂SiO₄ and Fe₀.₃Mg₀.₇SiO₃. In addition, increasing the SO₂ concentration and O₂ concentration increased the SO₃ concentration but increasing the SO₂ concentration decreased the SO₃ formation ratio.

Asbestos, as with other pollutants in the air, has adverse effects on the health of human beings and animals. Today, the relationship between presence of asbestos fibers in the air breathed by humans and developing serious diseases such as lung cancer (asbestosis) and mesothelioma has been proven. This study was designed and conducted within the time period of August 2017 and June 2018 to determine the concentration of asbestos fiber in the ambient air of Shahryar City and to evaluate their health effects for the general population of the city. For this purpose, samples were taken from four points, and overall 32 air samples were taken along the year. The samples were then analyzed by the phase contrast microscopy (PCM) method. Also, to investigate the type of asbestos and for more accurate counting of fibers, SEM analysis was utilized. Finally, based on the EPA IRIS method, the health effects resulting from asbestos risks were also evaluated. The results of this study indicated that the mean annual concentration of asbestos fiber in the ambient air of Shahryar City was obtained as 0.0019 f/ml PCM and 0.0072 f/ml SEM. Furthermore, the most polluted point was S1 point (0.0119 –0.0026 f/ml, PCM), while the lowest concentration was related to S4 point (0.001 f/ml PCM–0.0021 f/ml SEM). The mean annual risk resulting from airborne asbestos fiber in the ambient air of Shahryar City for all samples was obtained as 1.72 × 10⁻⁶ to 2.2 × 10⁻⁴, which was higher than the recommended risk range in some points.

Lead is one of the most widely used elements in the world. Lead can cause acute and chronic complications such as abnormal hemoglobin synthesis, kidney damage, abortion, nervous system disorders, male infertility, loss of learning ability, behavioral disorders, and even death. The aim of this study was to carry out quantitative and semi-quantitative risk assessments of exposure to lead among the solderers of the Neyshabur electronics industry. This cross-sectional, descriptive, and analytical study was conducted in 2017 and 2018 on 40 female soldering workers exposed to lead. Semi-quantitative risk assessment was carried out according to the Singapore Health Department and quantitative risk assessment according to the Office of Environmental Health Hazard Assessment (OEHHA) method. The average occupational exposure to lead in the electronics manufacturing industry was 93.89 ± 33.40 μg m⁻³ with a range from 9 to 150 μg m⁻³. Occupational exposure to lead in the industrial groups of initial soldering with an average of 130.37 ± 40.23 μg m⁻³ and cutting wires, electroplating, and coating bare parts with an average of 110.24 ± 30.11 μg m⁻³ was higher than the secondary soldering groups with an average of 90.78 ± 20.22 and shift supervisors with an average of 43.86 ± 10.97 μg m⁻³. The mean excess lifetime cancer risk (ELCR) was 0.11 per 1000 people and the mean non-carcinogenic risk (HQ) was 7.20. The results of this study indicate that there is a risk of non-carcinogenic complications among electronic solderers. Therefore, managers and employers should reduce lead exposure through engineering controls (substituting lead-free alloys, efficient ventilation) and management strategies such as reducing exposure hours.

Dibutyl phthalate (DBP), a persistent environmental pollutant, can induce neural tube abnormal development in animals. The possible effects of DBP exposure on human neural tube defects (NTDs) remain elusive. In this study, the distribution of DBP in the body fluid of human NTDs was detected by GC-MS. Then, chick embryos were used to investigate the effects of DBP on early embryonic development. Oxidative stress indicators in chick embryos and the body fluid of human NTDs were detected by ELISA. The cell apoptosis and total reactive oxygen species (ROS) level in chick embryos were detected by whole-mount TUNEL and oxidized DCFDA, respectively. The study found that the detection ratio of positive DBP and its metabolites in maternal urine was higher in the NTD population than that in normal controls. 8-hydroxy-2 deoxyguanosine (8-OHDG) and malondialdehyde (MDA) were evidently upregulated and superoxide dismutase (SOD) was observably downregulated in amniotic fluid and urine. Animal experiments indicated that DBP treatment induced developmental toxicity in chick embryos by enhancing the levels of oxidative stress and cell apoptosis. MDA was increased and SOD was decreased in DBP-treated embryos. Interestingly, the supplement of high-dose choline (100 μg/μL), not folic acid, could partially restore the teratogenic effects of DBP. Our data collectively suggest that the incidence of NTDs is closely associated with DBP exposure. This study may provide new insight for NTD prevention.

This simulation study is aimed to model a contemporary Proton Exchange Membrane fuel cell (PEMFC) CHP system having a ‘heat and power’ autonomy as well as a provision of demand-driven electrical supply to the grid. A novel nanowire-electrode PEMFC stack is adopted within this PEMFC CHP system so to effectively replace the existing natural gas fuelled durable solid oxide fuel cell (SOFC) CHP system installed at David Wilson Millennium Eco-house at University of Nottingham. The energy savings, environmental, and economic performances of the proposed PEMFC system are determined and compared to the base case (SOFC) which is operated continuously to maintain a 1.5 kWe. While to meetup the highly fluctuating and seasonal demands of heating and power like in the UK, a PEMFC is more productive and advantageous over a SOFC. The proposed PEMFC unlike to the SOFC will be able to operate and adjust its output and turn down instantly as per changing conditions of ambient temperatures and loads in terms of electricity and heat. The results of the modelling predicted that as compared to the base case scenario, this PEMFC CHP system will efficiently reduce an annual CO₂ emission by 65.99% and fiscal costs by 66.74% with a viable internal rate of return as 8.93% and benefit to cost ratio as 1.02.

Oxidative stress plays a significant role in the pathophysiology of numerous kidney diseases, generally mediated by reactive oxygen species (ROS). Arsenic (Ar) is known to exert its toxicity through the generation of ROS and inflammation. The current study investigates the protective effects of sulforaphane (SFN) against arsenic-induced renal damage via PI3K/Akt-mediated Nrf2 pathway signaling. Thirty-two male albino Wistar rats were randomly divided into four groups of eight animals each, designated as control, arsenic (Ar), sulforaphane plus Ar (SFN+Ar), and sulforaphane alone (SFN), with oral administration of Ar (5 mg/kg BW) and SFN (80 mg/kg BW) daily for 28 days. Ar administration significantly (P < 0.05) increased the levels of ROS, OHdG, Ar accumulation, and lipid peroxidation, and decreased levels of enzymatic and nonenzymatic antioxidants. Notably, a significant (P < 0.05) increase was observed in markers of apoptosis, DNA damage, TUNEL-positive cells, and dark staining of ICAM-1 in renal tissue with decreased PI3K/Akt/Nrf2 gene expression. The biochemical findings were supported by histopathological and electron microscopy evaluation, which showed severe renal damage in rats treated with Ar. Pretreatment with SFN significantly (P < 0.05) attenuated renal ROS, OHdG, lipid peroxidation, and DNA damage, and increased phase II antioxidants via PI3K/Akt-mediated Nrf2 activation in renal tissue. These results show that dietary supplementation with SFN protects against Ar-induced nephrotoxicity via the PI3K/Akt-mediated Nrf2 signaling pathway in the rat kidney.

Stormwater treatment requires effective control measures and development of low-cost and high-efficiency technologies. An integrated system is developed by combining a baffled vertical-flow constructed wetland (BVFCW) and a scenic water body for stormwater quality control purpose. The objectives of the study are to compare the pollutant removal performance of the full-scale integrated system with four groups of wetland-to-scenic water body area ratios (WSARs) including 1/11, 2/11, 3/11, 4/11 and investigate its treatment efficiency. Results show that the system performs better in the removal of chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH₄⁺–N), nitrate-nitrogen (NO₃–N), and total phosphorus (TP) at the WSAR of 4/11 than that at 3/11 in sixteen-day operation, while it reaches the highest total nitrogen (TN) removal efficiency of 74.0% at the WSAR of 2/11 due to relatively rich carbon source and high influent TN concentration. The integrated system may prove the most effective COD removal at the WSAR of 4/11 for four-time aerobic/anaerobic alternating conditions, a longer flow path and more time to contact with substrates, although the influent COD is lower than that at 2/11 and 1/11. After sixteen-day operation, BVFCW achieved COD removal rate of 90.3%, NH₄⁺–N removal rate of 85.7%, NO₃–N removal rate of 68.6%, and TP removal rate of 52.5% at the WSAR of 4/11. At the WSAR of 1/11, effluent met the Class IV requirements in Chinese standards after one-week operation, while effluent met the Class III requirements under the rest conditions. Since effluent in all WSARs met the standards, WSARs of 1/11 and 2/11 were recommended.

Trihalomethanes (THMs) and adsorbable organic halides (AOX) were generated in chlorinated water. The purpose of the study was to provide a comprehensive picture of concentration distribution, the seasonal and different water source variability of THMs and AOX. Data for THMs, AOX, and other physico-chemical parameters were from 538 samples of 16 drinking water work through a 3-year sampling program which was conducted in Shandong province with typical temperate and monsoonal climate. Selected samples were considered with the influence of factors such as season, water source, and disinfectant. The THMs and AOX concentration of the samples disinfected with chlorine ranged from 2.1–105 μg/L and 11–238 μg/L, respectively. The THMs and AOX concentration of the samples disinfected chlorine dioxide ranged from N.D.–47.6 μg/L and N.D.–102 μg/L, respectively. The median concentration of THMs and AOX of samples disinfected with chlorine were 35 μg/L and 61 μg/L, much higher than chlorine dioxide, respectively. Ninety-two percent of the samples disinfected with chlorine and all samples disinfected with chlorine dioxide met Chinese drinking water standard for THMs. The ratio of tribromethane (TBM) to THMs of samples disinfected with chlorine was 19%, lower than chlorine dioxide 42%. Bromine substitution factor (BSF) of THMs and initial concentration of bromide showed weak correlation, and the Spearman correlation coefficient was 0.38. THMs and AOX concentrations showed noticeable seasonal variations with the highest median concentrations in spring. The levels of THMs and AOX in drinking water varied with different water sources and followed the order local reservoir > Yellow River reservoir > ground water. The survey results complement the database of THMs and AOX occurrence in drinking water in China, and offer a significant reference data for setting disinfections by-products occurrence in countries or regions with similar climate around the world.