Journal of hazardous materials advances最新文献

Climatic conditions are one of the most important factors affecting the risk level associated with exposure to benzene, toluene, ethylbenzene, and xylene (BTEX) compounds. This systematic review and meta-analysis study aimed to investigate the impact of climatic conditions on carcinogenic and non-carcinogenic risk value changes during exposure to BTEX compounds. Five electronic bibliographic databases (Scopus, PubMed, Medline, Embase, and Web of Science) were systematically searched. The search algorithm consisted of three sets of keywords and their possible combinations. For different climatic conditions, the overall mean and 95 % confidence interval (CI) of the effect size related to the carcinogenic and non-carcinogenic risk of BTEX were calculated using a random effect model. 26 articles passed the inclusion/exclusion criteria and were included in this review. The highest values of the hazard quotient (HQ) for benzene, toluene, ethylbenzene, and xylene were in the summer season (53.3 %, 47.1 %, 73.3 %, 68.8 % of the studies) and in the winter season (33.3 %, 47.1 %, 20 %, and 25 % of the studies), respectively. Additionally, the highest values of carcinogenic risk (CR) for benzene and ethylbenzene were revealed in the summer season (50 % and 75 % of the studies) and in the winter season (33.3 % and 25 % of the studies), respectively. Based on the results of the meta-analysis also, risk values related to occupational and environmental exposures in summer were often higher than those in winter. These results can be used by policymaking to focus on decreasing exposure to BTEX, particularly in climatic conditions with higher hazards.

The emergence of microplastics (MPs) as microcontaminants in environmental drinking water sources is a problem in Africa that requires immediate action. Therefore, this review focused on understanding the sources of MPs in African water systems, treatment strategies, analytical methods for identification and quantification, and Africa's pollution index. From the findings, the source of MPs in African water systems was attributed to unregulated importation of plastic products, poor waste management, lack of awareness, poor environmental value system and the inability of local polymer industries to adjust to new policies on plastic management. Most studies identified microfibers and microbeads to be the primary sources of plastics that break down to MPs in African drinking water sources, with polystyrene (PS), polypropylene (PP), and polyethylene (PE) being frequently detected. Current methods for identification, and quantification of MPs in most studies conducted in Africa were not developed in Africa but was adopted from developed countries and, in some cases, modified to meet specific analytical requirements. More studies are necessary for in-depth understanding of the fate and pollution index of MP in African environmental water systems. Furthermore, the interaction between MP and other pollutants in the water system still needs to be better understood. This review suggests membrane and rapid sand filtration methods as promising methods that may be considered for removing MPs from water systems in Africa.

By 2030, the UN General Assembly issued Sustainable Development Goal 6 (SDG 6), which calls for the provision of safe drinking water; however, little progress has been made. Wastewater treatment and reuse have garnered significant attention owing to the increasing demand for sanitation and sustainable development practices. Multiple methods have been designed and tested, among which Aerobic Granular Sludge-based treatment is rapidly emerging as a promising treatment option. Aerobic Granular Sludge (AGS) plants have been the focus of research due to their low energy consumption, small footprint, and low unit costs. However, the full-scale application of AGS may be hindered by constraints such as strict nitrogen and phosphorus discharge standards, frequent and large temperature fluctuations, and fluctuating influent flow volume. Despite the existence of a few reviews related to AGS technology, there is a need for an extensive review coupled with a research progress analysis that provides comprehensive information on the nuances of AGS, which prompted this article. AGS technique and research progress in AGS are identified through a scientometric lens is reviewed in this article. The topics covered include the generation of AGS through the use of technology, usage, challenges associated with managing AGS plants, and a comparison between AGS and other methods of energy storage. An analysis was conducted to understand the keywords for which research is currently active: authors who have conducted more research, collaboration, and other bibliometric factors associated with AGS research.

Per- and poly-fluoroalkyl substances (PFAS) are widely used as surfactants in the oil and gas industry, presenting significant environmental and health risks due to their persistence and mobility. While prevailing research primarily targets PFAS removal from aqueous environments, this study explores the efficacy of nanosized cerium oxide nanoparticles (CeO₂ NPs) and traditional activated carbon (AC) in removing PFAS from organic media via adsorption and thermal degradation. Both adsorbents exhibited robust adsorption capabilities; however, their interaction mechanism with PFAS differ significantly. CeO₂ NPs primarily engage in chemical adsorption with PFAS, whereas AC relies on hydrophobic interactions. Additionally, CeO₂ NPs outperformed AC in thermal degradation experiments, achieving approximately 95 % decomposition of PFOS at 400 °C, compared to only 52 % with AC. Furthermore, the formation of stable Ce−F bonds at high temperatures significantly reduced fluoride ion release from CeO₂ NPs, underscoring their potential to minimize environmental impact. This study is the first to apply both AC and CeO₂ NPs for PFAS removal from organic media and to elucidate their distinct adsorption and thermal decomposition mechanisms, highlighting the superior performance of CeO₂ NPs in environmental remediation of PFAS.

Heavy metal(oid)s contamination in soil is a worldwide concerned issue, considering the potentially far-reaching hazards to ecosystem safe and human health. This study provides a comprehensive and systematic review on health risk assessment associated with soil HMs, and carries out a bibliometric analysis in terms of publication years, case distribution, land use characteristics, citation frequency and assessment models. The findings provide valuable knowledge for understanding research status, hotspots, limitations and future direction in assessing human health risks caused by soil HMs, revealing the rapid development and wide concern on this subject with 930 original articles across 67 countries, covering 21 HMs in 7 land use patterns. However, there is an urgent need for addressing uncertainties in quantifying the intricate relationship between HMs contamination and human health, which highlights the significance of probabilistic assessment methods, localized model parameters as well as the incorporation of bioaccessibility. This study contributes to enhance all-round understanding for soil HMs-related health risk assessment, and has broader prospects for performing a more precise and reliable health risk assessment to guide effective risk management.

Drinking water contamination with heavy metals from industrial activities is an important issue. In particular, the hexavalent chromium ions Cr (VI) which are classified as group (A) carcinogens. Our research reports an effective removal of hexavalent chromium from water through the use of BaTiO₃ (BTO) as a piezocatalyst. We meticulously prepared pure tetragonal BTO by optimizing the synthesis parameters. The optimized BTO catalyst was utilized for the removal of Cr(VI) under applied mechanical force and removed up to 96 % of Cr(VI) from the solution. Our kinetic study revealed that the reaction follows a pseudo-first order. Thermodynamic studies indicated that the reaction is most spontaneous at temperatures of 20 °C and concentrations of 20 ppm. Our proposed mechanism for removing Cr(VI) by BTO piezocatalysts suggests that only 15 % of chromium was removed by adsorption, while the rest was removed by reduction through the piezocatalytic process.

The treatment of waste plastics is currently one of the most urgent environmental issues, and disposable medical masks (DMMs) are becoming increasingly important in the recycling of waste plastics. This study employs thermogravimetric analysis (TGA) combined with infrared spectroscopy (IR) and mass spectrometry (MS), and pyrolysis/gas chromatography/mass spectrometry (PyGC-MS) to investigate the thermal degradation of DMMs, including pyrolysis characteristics, kinetics, and products distribution. DMMs are composed of five layers, i.e., layers 1, 2 and 3 are the mask body, layer 4 is the mask strap, and layer 5 is the nose clip. Except layer 4, all the other layers could be entirely decomposed at 500 °C and have similar pyrolysis properties to PP. Alkanes, olefins, and diolefins with a wide carbon number distribution are produced at low temperature, while light olefins are more likely to be generated at high temperature. Accordingly, a two-stage pyrolysis reactor is applied to decompose DMMs to valuable products. After optimizing the operating conditions, the yield of light olefins reaches a maximum of 70.4 wt% at 800 °C in the second-stage pyrolysis of DMMs, where the yields of ethylene, propylene, and butene are 12.0 wt%, 28.0 wt%, and 29.6 wt%, respectively.

Exposure to ambient formaldehyde can be associated with hazardous consequences. It can be affected by seasonal and meteorological parameters. This study was performed to investigate the variation in exposure to ambient formaldehyde at different times of the year in various countries. A literature search was performed in five databases of Scopus, PubMed, Web of Science, Medline, and Embase. The search strategy was based on PRISMA protocols. The pooled values of ambient exposure to formaldehyde were computed by meta-analysis for all seasons. 44 articles were evaluated in this study. Based on the results, the concentrations of exposure to this substance in 13 of 20 studies in spring (65.00 percent), 29 of 38 studies in summer (76.32 percent), 12 of 17 studies in autumn (70.59 percent), and 15 of 37 studies in winter (40.54 percent) were higher than permissible value recommended by Texas Commission on Environmental Quality (3.3 µg/m³) for long exposure. The highest concentration of exposure to ambient formaldehyde was observed in Iran (23.93 µg/m³) in spring, in China (26.38 µg/m³) in summer, in China (15.0 µg/m³) in autumn, and in China (45.56 µg/m³) in winter. The pooled concentrations (μg/m³) of formaldehyde in spring, summer, autumn, and winter seasons were estimated as 5.78 (95 % CI: 4.82–6.75), 6.57 (95 % CI: 5.85–7.29), 6.07 (95 % CI: 4.76–7.39), and 3.59 (95 % CI: 3.17–4.01), respectively. The concentrations of formaldehyde in environmental settings tend to be mostly higher during the summer compared to other seasons. Perception of the fluctuations in formaldehyde concentration due to seasonal and meteorological changes is beneficial for air quality management.

Various studies are being carried out on the removal of organic dyes and the production of antibacterial agents. In this study, boron-doped carbon quantum dot (BCQD) was synthesized by hydrothermal method, and BCQD@g-C₃N₄ nanocomposite structure was synthesized using graphitic carbon nitride (g-C₃N₄) as the support material. The photocatalytic activity of the synthesized nanocomposite against MO, RhB dyes, and Escherichia coli (E. coli) bacteria was investigated. The surface, morphology, molecular, and crystal properties of BCQD@g-C₃N₄ were investigated using characterization methods such as Transmission electron microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), Fluorescence (FL) spectrophotometer, and X-ray diffraction (XRD). As a result of TEM analysis, it was determined that the average particle size of BCQD was 5.1 ± 1.14 nm and showed a homogeneous distribution on 2D g-C₃N₄. In the XRD spectrum for BCQDs, the diffraction peak corresponding to the (002) amorphous carbon phase was observed at 21.65° In the PL spectrum of B-CQD@g-C₃N₄s, the emission value was observed at 458 nm. In the study conducted by taking advantage of the photocatalytic feature of BCQD@g-C₃N₄ nanocomposite, Rhodamine B (RhB) and Methyl orange (MO) were degraded by 65.58 % and 73.56 %, respectively, at the end of 120 min. Additionally, BCQD@g-C₃N₄ photocatalyst completely inhibited the growth of E. coli bacteria, which are frequently encountered in wastewater, at 90 minutes under sunlight. Escherichia coli (E. coli), which is frequently encountered in wastewater, BCQD@g-C₃N₄ completely prevented bacterial growth in the 90^th minute under sunlight.