For elimination of cesium from aqueous solutions, mesoporous SBA-15 was synthesized and employed as the support for immobilization of potassium copper hexacyanoferrate. The synthesized adsorbent was characterized by various techniques and was used for adsorption of cesium. The results indicated that its adsorption capacity was 174.80 mg/g and superior to many studied adsorbents. The adsorbent represented good selectivity in the presence of some studied co-existing. The Temkin, Redlich–Peterson, Sips, Langmuir, and Freundlich isotherm models were used to evaluate the experimental data. The error analysis performed by EABS, ERRSQ, and HYBRID methods showed that the data was in good agreement with the Langmuir model indicating that the process was monoenergetic and the uptake of cesium forwarded through monolayer process. The pseudo-second-order model was recognized as the adequate model to describe the kinetic data of the adsorption process. The adsorption process was endothermic and spontaneous. The regeneration tests revealed that the adsorbent retained most of initial capacity after recovery.

In this study, pine needles were used as biomonitors to investigate the levels, spatial distributions, and possible sources of polybrominated diphenyl ethers (PBDEs) and four emerging halogenated flame retardants (HFRs) in the atmosphere of Shanghai, China. The four emerging HFRs were hexabromocyclododecane (HBCD), decabromodiphenylethane (DBDPE), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), and dechlorane plus (DP), with the first 3 HFRs being non-polybrominated diphenyl ether brominated flame retardants (non-PBDE BFRs). The total concentrations ranged from 3.71 to 4020 ng g⁻¹ dry weight (dw) for 52 PBDE congeners (Σ₅₂BDEs), < MDL (method detection limit) to 15.2 ng g⁻¹ dw for three non-PBDE BFRs (Σ₃non-PBDE BFRs), and 0.815 to 1090 pg g⁻¹ dw for two DP isomers (ΣDP), respectively. High levels of PBDEs, three non-PBDE BFRs, and DP were found in pine needles from suburbs and Pudong, which was a consequence of industrial activities. The fraction of anti-DP isomer (fₐₙₜᵢ) in pine needles ranged from 0.515 to 0.939 with a mean value of 0.721, and most of the fₐₙₜᵢ values were consistent with those of technical DP formulations. Principal component analysis-multiple linear regression (PCA-MLR) model identified four sources of PBDEs in pine needles with the quantified contributions: degradation of technical PBDE formulations (49.5%), technical deca-BDE (6.9%), technical penta-BDE (25.1%), and technical octa-BDE (18.5%). These findings are expected to help understand the pollution level, fate, and possible sources of HFRs in the atmosphere of Shanghai and provide a basis for air pollution control and management in Shanghai.

The growing appreciation of distance decay as an important parameter necessary for estimating willingness to pay (WTP) is hugely recognized in the literature. In this paper, we estimated the extent to which distance decay and individual’s socioeconomic characteristics influence the WTP for restoration of environmental quality attributes in the Heihe River Basin. A choice experiment technique was used to evaluate the household’s WTP for the improvements in local environmental attributes. The results of mixed logit model significant impact of distance on the individual’s WTP for the improvements in environmental attributes. Findings of the study revealed that people living within 25 km from the river are willing to pay more for an increase in the river water quality level, a reduction in sandstorm days, and an increase in the area of the east Juyan Lake than the people living within the range of 50 km and much more compared to 50 km away from the river. Based on the socioeconomic characteristics, it is concluded that the level of education, age, household’s annual income, and household size have a significant effect on the WTP. Results of the implicit prices for each attribute showed the preferences of the inhabitants for every attribute, where the highest WTP in pooled data was recorded for river water quality level (i.e., RMB 124.81/year) and the lowest for leisure and entertainment (i.e., RMB 0.40/year). The highest WTP for water quality suggests that water quality level was the most favored attribute compared to others, subject to the given conditions of water quality and the river basin.

The simultaneous adsorption of both imazalil (IMZ) and thiabendazole (TBZ) fungicides in a Cu²⁺-exchanged Mt was studied in this work. Kinetic studies were used to determine the rate law which describes the adsorption of individual fungicides onto the adsorbent. Adsorption isotherm of individual and combined fungicides was done to evaluate synergic or antagonistic effects. The Mt-Cu material considerably improved TBZ and/or IMZ adsorption from aqueous suspensions with respect to raw Mt, leading to removal efficiencies higher than 99% after 10 min of contact time for TBZ and IMZ Cᵢ = 15 and 40 mg/L, respectively, when a solid dosage = 1 g/L was used. The adsorption sites involved were determined by a combination of X-ray diffraction (XRD) determinations and electron paramagnetic resonance (EPR), indicating that fungicides were bonded to Cu²⁺ cations, while the rate limiting step was the formation of coordination bonds. The adsorption mechanism proposed is that of ligand exchange between water and fungicide molecules in the metal coordination sphere. The single-crystal structure for the IMZ-Cu²⁺ complex indicated that four molecules were bounded to the copper centers, while two molecules of TBZ are bounded to copper explaining the higher IMZ uptake capacity for the Mt-Cu material. Graphical abstract

The study focuses on the estimation of health risk from nitrate present in the drinking water and vegetables in Nagpur and Bhandara districts in the state of Maharashtra, India. Drinking water samples from 77 locations from the rural as well as urban areas and 22 varieties of vegetable were collected and analyzed for the presence of nitrate for a period of 1 year (two seasons). The daily intake of nitrate from these water and vegetable samples was then computed and compared with standard acceptable intake levels to assess the associated health risk. The mean nitrate concentration of 59 drinking water samples exceeded the Bureau of Indian Standards limit of 45 mg/L in drinking water. The rural and urban areas were found to have mean nitrate concentration in drinking water as 45.69 ± 2.08 and 22.53 ± 1.97 mg/L, respectively. The estimated daily intake of drinking water samples from 55 study sites had nitrate concentration far below the safety margin indicating serious health risk. The sanitation survey conducted in 12 households reported contaminated source with positive E. coli count in 20 samples as the major factor of health risk. The average nitrate concentration was maximum in beetroot (1349.38 mg/kg) followed by spinach (1288.75 mg/kg) and amaranthus (1007.64 mg/kg). Among the samples, four varieties of the vegetables exceeded the acceptable daily intake (ADI) with an assumption of 0.5 kg consumption of vegetables for an average of a 60-kg individual. Therefore, irrigation of these locally grown vegetables should be monitored periodically for nitrogen accumulation by the crop above the ADI limit. The application of nitrogenous fertilizers should also be minimized in the rural areas to help protect the nitrate contamination in groundwater sources.

Wheat straw is an abundant agricultural waste that is rich in lignocellulose. However, its waxy surface, highly crystallized structure, and limited surface area make it difficult to be hydrolyzed and used efficiently by microorganisms. Liquid hot water (LHW) pretreatment was studied to explore the feasibility of improving the methane yield of wheat straw in anaerobic digestion (AD). The results showed that the crosslinking structure of wheat straw was broken by LHW pretreatment. Some pores and cracks appeared on the surface of the pretreated wheat straw, increasing the microbial attachment sites. Under different hydrothermal temperatures (150–225 °C) and retention times (5–60 min), the degradation of hemicellulose ranged from 27.69 to 99.07%. The maximum methane yield (201.81 mL CH₄/g volatile solids) was achieved after LHW pretreatment at 175 °C for 30 min, which was a 62.9% increase compared with non-treated straw. LHW at high temperatures such as 225 °C was not suitable for the AD of wheat straw. Methane yield results were fitted with the first-order and modified Gompertz equations to evaluate the hydrolysis rate and inhibitory effects of the pretreated materials in AD.

The purpose of this study was therefore to investigate the effects of radiotherapy on the kidney and the potential use of agents such as N-acetylcysteine (NAC) in developing a future therapeutic protocol for radiation-induced nephrotoxicity at the histopathological and biochemical levels. Our study consisted of three groups: control (oral saline solution only; group 1), irradiation (IR; group 2), and NAC + IR (group 3). The irradiation groups received a single dose of whole-body 6-Gy x-irradiation. The NAC group received 300 mg/kg by the oral route for 7 days, from 5 days before irradiation to 2 days after. All subjects were sacrificed under anesthesia 2 days after irradiation. IR increased tubular necrosis scores (TNS), MDA, and caspase-3 expression, while reducing renal tissue GSH levels. We also observed dilation in renal corpuscles and tubules. Capillary congestion was present in the intertubular spaces. NAC reduced the levels of TNS, MDA, and caspase-3 expression, but increased the levels of renal tissue GSH. ROS-scavenging antioxidants may represent a promising means of preventing renal injury in patients undergoing radiotherapy.

Environmental pollution analysis should be present in scientific research. The more organized the environmental laws of a particular place, the smaller the risks imputed to the ecosystem. The environmental damages that irregular waste from industrial effluents can cause are notorious. However, Brazil lacks extensive legal regulation, which is an embryonic legal matter. There is no specific law regulating a National Industrial Effluent Policy, dealing with the treatment and final disposal of these chemical compounds. Until a solid legal structure has been formalized on the treatment and final disposal of industrial effluents in Brazil, it is necessary that scientific researches optimize techniques capable of causing lower environmental impacts, so as to avoid possible pollution to the bodies of water. This article defends the argument that it is possible to elaborate legislation on the treatment and final disposal of industrial effluents in Brazil, through the application of engineering techniques, specifically through numerical simulation, by using the discrete elements method or particles method. The present case study is the Camaçari Petrochemical Pole, state of Bahia, which is the largest integrated industrial complex in the Southern Hemisphere, composed of more than 90 companies in the chemical and petrochemical areas. All the effluents from this locality are treated by CETREL (Liquid Effluent Treatment Plant). Particle analysis was performed in CETREL tanks to illustrate how numerical simulations can be applied to investigate the treatment of industrial effluents and, consequently, to affirm the importance of developing procedures and norms for this matter. It is believed that this article brings relevant information to support a future law that regulates a Brazilian National Policy of Industrial Effluents.

The consequence of carcinogenic and non-carcinogenic health risks of the heavy metal concentrations in street dust of North Cyprus is yet to be reported. This study is aimed at investigating the concentration of six different heavy metals’ concentration explicitly: As, Cu, Zn, Ni, Cr, and Pb, along leading highways in Nicosia. The result obtained was analyzed using an X-ray fluorescent machine. Multivariate and statistical methods were applied for the data analysis using xlstat MS-excel; furthermore, index of geo-accumulation (Igeo) and human health risk assessment using exposure pathways as defined by United State Environmental Protection Agency (USEPA) pollution mode were also used for level assessment and health risk implications. The average (M ± SD) concentrations of the metals in the dust are as follows: As (17.48 ± 1.53 mg/kg), Cu (51.86 ± 8.60 mg/kg), Cr (321.14 ± 8.20 mg/kg), Pb (35.62 ± 8.54 mg/kg), Ni (64.79 ± 8.72 mg/kg), and Zn (136.13 ± 30.85 mg/kg). Variation coefficient, Vc, and principle component analysis (PCA) suggested that As, Cr, Ni, and Pb have same source of pollution emission from both natural and anthropogenic activities, Zn from traffic emission while Cu from natural source. However, the result was compared with other nearby towns bordering North Cyprus; all the metal shows similar pattern of pollution with the exception of Cr which is 5 and 11 times higher than street dust of Amman (Jordan) and Tokat (Turkey), respectively. Additionally, Igeo result has the following decreasing order: Zn > Cr > Pb > Ni > Cu > As and also revealed that the As, Cu, and Ni have originated from natural source. Cr has mix source: one from traffic and the other one from atmospheric deposition. Also, Pb is emitted from industrial pollution, whereas 80% of Zn are from traffic-related emissions. The non-carcinogenic health risk (hazard quotient (HQ) and hazard index (HI)) follows the order Cr > As>Ni > Pb > Zn > Cu for children and adults. It is found that the HI of As, Cu, Ni, Pb, and Zn is less one; hence, the street dust does not exhibit non-carcinogenic health risk. But that of Cr content is greater than one, with HI values of Cr 1.44E+02 and 1.55E+01 for children and adults, respectively. The result for carcinogenic health risk (total cancer risk (TCR)) has the following order: Pb (1.42E−05) > Cr (4.81E−09) > (Ni 1.35E−09) > As (1.96E−10). With all the values less than threshed hole limit of TCR ≥ 10⁻⁴, street dust does not possess carcinogenic health risk for the entire values of six heavy metals considered in this work.

This paper determines the impact of two clay minerals (kaolinite and montmorillonite) and three oxides (goethite, δ-MnO₂, and bayerite) on the elemental composition and FTIR spectra of humic-like acid (HLA) extracted from microbial-mineral residue formed from the microbial utilization of lignin in liquid shake flask cultivation. Goethite, bayerite, and δ-MnO₂ showed higher enrichment capabilities of C and O + S in the HLA than kaolinite and montmorillonite. Goethite showed the highest retention of organic C, followed by bayerite, but kaolinite exhibited the least exchangeability. Kaolinite and montmorillonite enhanced microbial consumption of N, resulting in the absence of N in HLA. A few aliphatic fractions were preferentially gathered on the surfaces of kaolinite and montmorillonite, making the H/C ratios of HLA from the clay mineral treatments higher than those of HLA from the oxide treatments. δ-MnO₂ was considered the most effective catalyst for abiotic humification, and goethite and bayerite ranked second and third in this regard. This trend was proportional to their specific surface areas (SSAs). However, comparing the effects of different treatments on the promotion of HLA condensation by relying solely on the SSA of minerals was not sufficient, and other influencing mechanisms had to be considered as well. Additionally, Si–O–Al and Si–O of kaolinite participated in HLA formation, and Si–OH, Si–O, and Si–O–Al of montmorillonite also contributed to this biological process. Fe–O and phenolic –OH of goethite, Mn–O of δ-MnO₂, and Al–O of bayerite were all involved in HLA formation through ligand exchange and cation bridges. Lignin was better protected from microbial decomposition by the kaolinite, bayerite, and δ-MnO₂ treatments, which caused lignin-like humus (HS) formation. Under the treatments of δ-MnO₂, goethite, and bayerite, HLA showed a greater degree of condensation compared to HLA precipitated by kaolinite and montmorillonite. Contributions from Si–O, and Si–O–Al of clay minerals, and Fe–O, Mn–O, and Al–O of oxides were the mechanisms by which minerals catalyzed the formation of HS from lignin.