This study systematically reviewed all the cohort studies investigating the relationship between long-term exposure to PM₂.₅ and any health outcome until February 2018. We searched ISI Web of Knowledge, Pubmed, and Scopus databases for peer-reviewed journal research articles published in English. We only extracted the results of the single-pollutant main analysis of each study, excluding the effect modifications and sensitivity analyses. Out of the initial 9523 articles, 203 articles were ultimately included for analysis. Based on the different characteristics of studies such as study design, outcome, exposure assessment method, and statistical model, we calculated the number and relative frequency of analyses with statistically significant and insignificant results. Most of the studies were prospective (84.8%), assessed both genders (66.5%), and focused on a specific age range (86.8%). Most of the articles (78.1%) had used modeling techniques for exposure assessment of cohorts’ participants. Among the total of 317 health outcomes, the most investigated outcomes include mortality due to cardiovascular disease (6.19%), all causes (5.48%), lung cancer (4.00%), ischemic heart disease (3.50%), and non-accidental causes (3.50%). The percentage of analyses with statistically significant results were higher among studies that used prospective design, mortality as the outcome, fixed stations as exposure assessment method, hazard ratio as risk measure, and no covariate adjustment. We can somehow conclude that the choice of right characteristics for cohort studies can make a difference in their results.

This study aimed to investigate the protective effects of Eugenol (EUG), an effective antioxidant phenolic compound with a radical scavenging activity against citrinin (CTN)-induced toxicity in vitro using HCT116 cells. CTN is a well-known mycotoxin found in different constituents of the food chain. This environmental contaminant produces free radicals which interacts with cellular macromolecules and produces oxidation of protein, lipid, and DNA. The cytotoxic effects were monitored by measuring cell viability, reactive oxygen species (ROS) generation, antioxidant enzyme activities, malondialdehyde (MDA) production, protein oxidation, and DNA fragmentation. Our results have shown that the pretreatment of HCT116 cells with EUG, 2 h prior to citrinin (CTN) exposure, significantly decreased CTN-induced cell death, inhibited ROS generation, modulated activities of both catalase (CAT) and superoxide dismutase (SOD), and reduced MDA production. Level of protein-bound sulfhydryls and DNA fragmentation were also declined as compared with CTN-treated cells. These findings suggest that EUG would be an effective protective agent against CTN-induced oxidative stress, and thereby, it may complement and add to the functions of antioxidant vitamins and enzymes as a protection against the cytotoxicity of this mycotoxin.

Synthesis of silicon materials from fly ash is an ecologically justified process aimed at the transformation of energy sector waste-fly ash into mesoporous silicon material of broad possible application field. In this study, the MCM-41-NH₂ was successfully synthesized from industrial solid waste fly ash via a facile and fast process of alkali fusion method under the assistant of microwave. Due to the employ of microwave, the aging time was controlled within 30 min, which was significantly shorter than that of traditional hydrothermal method (48–72 h). And, the obtained MCM-41-NH₂ was shown an excellent performance to remove Cr(VI) from solution under the investigation of fixed-bed column. The maximum adsorption capacity for Cr(VI) was 53.77 mg/g. Additionally, the effect of initial concentration, flow rate, bed height, and pH on Cr(VI) removal were investigated, and the models of Thomas and Adams–Bohart were applied to predict the experiment data; the correlation coefficients (R²) of Thomas model under the investigated conditions were all close to 1. Furthermore, the adsorbent was characterized by N₂ adsorption–desorption isotherm, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), zeta potential, ultraviolet-visible spectroscopy (UV-vis), X-ray photoelectron spectroscopy (XPS), and NH₃-Temperature Programmed Desorption (NH₃-TPD). The results showed that amino groups play an important role in the adsorption process. Cr(VI) was firstly adsorbed on the surface of the MCM-41-NH₂, and then some of the adsorbed Cr(VI) were reduced to Cr(III) by the release of the protons of the ammonium. The information showed that MCM-41-NH₂ could be an effective and low-cost sorbent for removing Cr(VI) from wastewater. Furthermore, recycling experiments showed that the spent adsorbent had high catalytic performance for methyl mercaptan (CH₃SH). Graphical abstract .

Activated carbon and biochar were obtained from chicken bone (CB), characterized, and applied to remove basic fuchsine from aqueous media. The adsorbent dosage and pH effects were studied, as well as kinetic, equilibrium, and thermodynamic curves were constructed. The values of BET surface area and total pore volume were 108.94 m² g⁻¹ and 0.219 cm³ g⁻¹ for the activated carbon and, 18.72 m² g⁻¹ and 0.075 cm³ g⁻¹ for the biochar. The dye removal percentages were 93.63 and 55.38% when 2.5 g L⁻¹ of activated carbon and biochar were used, respectively. The adsorption was favored using 0.5 g L⁻¹ of adsorbent and pH of 7.0. Adsorption kinetics was well represented by the pseudo-second-order model. Langmuir model was the best to represent the equilibrium. Maximum adsorption capacity was 260.8 mg g⁻¹, obtained using activated carbon. The process was endothermic, favorable, and spontaneous. Results showed that alternative carbonaceous materials can be obtained from chicken bones and used as adsorbents to treat colored effluents containing fuchsine.

Use of sodium chloride to preserve animal skins and hides is becoming increasingly untenable due to stringent environmental regulations. In the present research work, a combination of sparingly soluble alkali and water-soluble polymer of ethylene oxide has been used to preserve skins with an objective of total elimination of common salt for preservation. A comprehensive study has been made for evaluating various parameters, such as dehydration and rehydration behaviours of skins, microbial growth, emission loads and physico-chemical characteristics of the cured skin to validate the salt-free preservation system developed. The shrinkage temperature, denaturation temperature and mechanical strength of tanned leather were analysed by using shrinkage, differential scanning calorimetric and thermomechanical analysis techniques. The new curing system has been found to be effective in preserving the skin as indicated by the various parameters studied and the final leather quality. The significant reduction in total solids content such as dissolved solids and suspended solids present in the effluent compared to conventional preservation method is evident from environmental impact assessment studies.

There has been a conflicting issue in rural China that whether or not encouraging the development of medium–large-scale biogas plants (MLBPs) to reduce household biogas digesters (HBDs) will be better for China in the long run. In this study, we investigate the difference between HBD users and MLBP users and the factors that affect the biogas use of these two user types on the basis of a survey of 1125 households in four provinces in China. The results indicate that compared to HBD users, MLBP users have a higher ratio (29%) of biogas use, obtain a higher subsidy-to-cost ratio (25%), and present a more positive evaluation of biogas service (3%). For HBD users, installation years and service evaluation are significant predictors of biogas use. For MLBP users, in addition to installation years and service, the subsidy-to-cost ratio affects biogas use negatively, and the biogas price is a key constraint for biogas use. These results provide valuable insights into the future development of biogas energy in rural China and guidance for the development of biogas in similar countries worldwide.

The aim of this study was to verify the effects of the isolated forms of Boral® SC 500, Glifosato® Biocarb herbicides, and a blend of both herbicides on metabolism and oxidative balance markers of Rana catesbeiana tadpoles and on their nutritional condition. Groups of tadpoles were divided into different treatments: control (no herbicides), Boral® 500 SC (sulfentrazone: 130 μg/L), Glifosato® Biocarb (glyphosate: 234 μg/L), and a blend of both herbicides. After 7 days, the liver, caudal muscle, and blood samples were taken to subsequently perform the biomarkers determination by spectrophotometry. The intestinal condition factor increased in animals exposed to glyphosate and herbicide blends, suggesting a hyperphagic effect. This hypothesis was confirmed by the rise of triglycerides and circulating very low–density lipoprotein (VLDL). There was a significant increase in the levels of uric acid in tadpoles exposed to the herbicide blend. Corticosterone levels reduced significantly in animals exposed to glyphosate and the herbicide blend. Oxidative stress markers had a tissue-dependent response. In the liver, glutathione S-transferase increased, and superoxide dismutase and catalase decreased in animals exposed to sulfentrazone and glyphosate. Lipoperoxidation was reduced in the glyphosate treatment. In the caudal muscle, superoxide dismutase and catalase activities were maintained, and there was a decline in the levels of glutathione S-transferase and TBARS only in the blend group.

The present work was carried out to quantify microplastics (MP) from three sandy beaches along the Côte d’Opale coastline located in the Hauts-de-France region of northern France. Three different study sites located along the English Channel were investigated due to different levels of anthropopression and hydrodynamic conditions. Sediments were collected at three different tide lines: high tide line (HTL), middle of the intertidal zone (IZ), and low tide line (LTL), to investigate the effects of tide line on microplastic contamination. Particles and fibers were counted and colors were recorded; polymer identification was then performed using pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS). Particle and fiber abundances ranged from 23.4 ± 18.9 to 69.3 ± 30.6 items kg⁻¹ dry weight sediment, with a trend towards fiber predominance, were observed. No difference in particle and fiber abundance was found between the different beaches and tide lines, except for Boulogne-sur-Mer, where the particle number was significantly different between tide lines. Major polymers identified were polyethylene (36.6%) and polypropylene (10.7%). This citizen science project provided preliminary data about the abundance and polymeric nature of MP along the Côte d’Opale coastline.

Trace element distribution in the human body varies across regions and countries due to their different living environment and lifestyle. Thus, it is of great significance to investigate the reference level of trace element in a specific population. Wuhan is the largest metropolitan area in central China with highly developed heavy industries. This study aimed at determining the reference urinary distribution in general populations of Wuhan for nine trace elements (Cr, Mn, Cu, As, Se, Cd, Hg, Tl, Pb), and analyzed their associations with age, sex, and the kidney function. In total, 226 healthy adults not exposed to these trace elements were recruited, and the first-morning urine specimens were analyzed by using ICP-MS-based method. Our results showed higher urinary levels for As and Cd in Wuhan population when compared with other countries, while other element levels were almost equivalent. Sex difference existed for urinary Cu, Mn, As, Tl, and Pb. And urinary Cd, Tl, and Pb levels were associated with the glomerular filtration rate. Almost all these urinary elements showed significant inter-correlations, especially for Cu but except for Mn. This study provides systematic information regarding urinary trace element levels in residents of Wuhan in central China, and shall be of importance for future environmental and occupational biomonitoring.

While the application and discharge of carbon nanomaterials (CNMs) increased rapidly, the research on the environmental safety of CNMs is also increasing. The high dispersity and mobility of modified CNMs in environmental media may have impacts on the environmental behavior of heavy metals. This work mainly studied the effect of fullerol nanoparticles (C₆₀(OH)ₙ) on Cu²⁺ transport, sorption, and release in water-saturated porous media. The results showed that due to the strong adsorption capacity of C₆₀(OH)ₙ for Cu²⁺, the transport of Cu²⁺ could be facilitated. However, with the pre-existence of C₆₀(OH)ₙ in porous media, the transport of Cu²⁺ was also slightly enhanced. In addition, when loaded into the pre-contaminated porous medium, the C₆₀(OH)ₙ also enhanced the release of retained Cu²⁺, which implies a high environmental risk of C₆₀(OH)ₙ.