Journal of hazardous materials advances最新文献

Contamination of borehole water by leachates from dumpsites has significantly affected the health of those who use polluted water for domestic activities. This study evaluated the seasonal variations of risks associated with potentially toxic elements in underground water sources near a dumpsite in Awka, Nigeria. The levels of the potentially toxic elements (PTEs) were compared with the World Health Organization (WHO) and Nigerian standard for drinking water quality (NSDWQ) standard limits. The, sources of PTEs, metal pollution index, water quality index, ecological risk, and health-related risks of using the underground water were evaluated. The chemical results indicated that levels of Cd and Pb were above the WHO and NSDWQ threshold limits for potable water. The Mn and Ni values were above the NSDWQ limits for potable water. The study borehole samples had PTE levels higher than the control samples due to their proximity to the landfill. The water quality index ranged from 1290.29 to 2243.04, showing that the water is unsuitable for drinking and other domestic uses. The metal pollution indices of the underground water samples were above 1, indicating that the water needs treatment before use. The health risk examination highlighted that children are more disposed to non-cancer risk than adults based on the hazard indices obtained. Also, the probability of cancer risks was high, showing that both children and adults are likely to be in danger of cancer risks. However, the ecological risk indices ranged from 11.187 to 51.581, indicating a low ecological risk. Pearson's correlation and principal component analysis revealed that the sources of pollution are from similar origins/sources linked to anthropogenic activities. Awareness programs are necessary to educate the populace about the dangers of using contaminated water. Effective waste management strategies and water treatment techniques should be implemented.

Spices consumption is the main pathway for human exposure to certain environmental pollutants. This study was aimed to evaluate the concentration of heavy metals such as cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganes (Mn), lead (Pb) and zinc (Zn) in different parts of various spices samples in Arba Minch Ethiopia. The average levels of metals in white cumin, fenugreek, black cumin, turmeric, basil, cardamom, and coriander were varied in the range 0.35–1.8, 1.02–11.96, 1.69–32.19, 20.74–38.98, 7.38–26.01, 2.96–9.57 and 5.38–44.63 mg/kg for Cd, Cr, Cu, Fe, Mn, Pb and Zn, respectively. Principal component analysis (PCA) showed that the robust linkage between Zn, Cr, and Mn in PC1, Cu and Pb in PC2, and Cd and Fe in PC3 comprising 39.10 %, 25.72 % and 18.57 % of the total variance, respectively. The average daily intake values were calculated in the range 5.22 × 10^–5–2.69 × 10^–4, 1.52 × 10^–4–1.78 × 10^–3, 2.53 × 10^–4–4.81 × 10^–3, 3.09 × 10^–3–5.82 × 10^–3, 1.1 × 10^–3–3.88 × 10^–3, 4.42 × 10^–4–1.43 × 10^–3, and 8.18 × 10^–4–6.66 × 10^–3, for Cd, Cr, Cu, Fe, Mn, Pb and Zn, respectively. The target hazard quotient (THQ) and hazard index (except in white cumin and fenugreek) for heavy metals in various spices were lower than the acceptable limit of unity (THQ and HI $<$1). The carcinogenic risk values were in the acceptable threshold limit (1 × 10^–6–1 × 10^–4), indicating that consuming different spices in the studied area will not pose a potential health risk to human health.

Textile wastewater (WW) is a complex mixture of dyes, salts, organic matter, and other chemicals that can negatively affect the environment if not properly treated. The progress made in integrated anaerobic/aerobic (A/O) WW treatment method is believed to be efficient and practical for textile dyeing WW compared to the conventional activated sludge (CAS) process. This study aims to critically review the efficacy and feasibility of integrated A/O process for textile WW treatment, the underlying dye degradation mechanisms, and the different factors affecting biodegradation. Moreover, the potential of haloalkaliphilic and thermophilic microorganisms is highlighted as they are the best candidates for textile WW treatment. The performance of the A/O treatment system in removing color, COD, and TKN was demonstrated to be highly effective, achieving reductions of up to 100 %, greater than 90 %, and 80 %, respectively.Anaerobes play a crucial role in breaking down complex organic matter during the anaerobic phase, which is subsequently converted into non-toxic byproducts by aerobes in the aerobic reactor, making the process effective in mitigating adverse environmental impacts. Recently, the performance and efficiency of biological treatment processes have been improved using this treatment system, enabling the textile industry to meet the requirements for effluent discharge standard limits. Nevertheless, further research and practical applications are still in their infancy stage; hence, additional exploration of the practicality of these concepts, including scalability and sustainability, as well as policy recommendations for their implementation, is imperative.

The current study aimed to investigate the effect of green tea extracts (GTEs) containing 35 % epicatechins on the bioaccessibility of amine surface functionalized polystyrene microplastics (APSMPs), the cellular integrity of intestinal membrane, intestinal absorption, microstructural changes, and aggregation of APSMPs using in vitro digestion with a Caco-2 cell system. The bioaccessibility of APSMPs with GTEs in the ratio of 1:1, 1:2, and 1:5 was observed to be 12.31 ± 0.14, 3.18 ± 0.09, and 1.79 ± 0.16 %, respectively. The trans-epithelial electrical resistances (TEER) value was enhanced while the intestinal transport of APSMPs significantly was decreased by the co-treatment of GTEs. The average particle size of APSMPs treated with GTEs after in vitro digestion became larger in a GTEs dose-dependent manner. The zeta potential value of -12.15 mV exhibited by the APSMPs with GTEs at a 1:2 (v/v) ratio indicates a substantial interparticle agglomeration, implying that APSMPs strongly were bound to GTEs during digestion. Particularly, Epigallocatechin gallate (EGCG) from GTEs treated with APSMPs mostly decreased during digestion, indicating that EGCG was the main component bound to APSMPs. Results from the current study suggest that GTEs could make APSMPs insoluble by aggregation due to a charge difference between APSMPs and the bioactive components present in GTEs.

Bangladesh is one of the hubs of the textile industry in the world; consequently, microfibers are an emerging threat to the aquatic ecosystem. Traditional effluent treatment plants (ETPs) might not be capable of removing most emerging pollutants like surfactants, dyes, and additives, including microfibers, and the textile industry may be a major source of microfiber pollution through products and ETPs. This study investigated the eleven woven, knit, and denim industries' ETP microfiber abundance and removal efficiency. The average (range) of microfibers found in influent, effluent, and sludge samples was 615.45 ± 377.52 particles/L (170−1460), 212.72 ± 80.14 particles/L (130−380), and 10545.45 ± 7989.54 particles/kg (4400−31000), respectively. The abundant shape was fiber, and most microfibres had sizes between 0 and 100 μm. Eight distinct colors of microfibers were found in the samples; black was the most abundant color among all the samples, followed by brown and blue. The studied ETPs showed a 23.52 % to 82.19 % microfiber removal rate, which is not satisfactory for minimizing pollution. The Fourier transform infrared (FTIR) analysis revealed that the main polymers in the samples were nylon, ethylene-vinyl acetate (EVA), polyethylene terephthalate (PETE), acrylonitrile butadiene styrene (ABS), cellulose acetate (CA), low-density polyethylene (LDPE or linear LDPE), and high-density polyethylene (HDPE). The contamination factor (CF) and pollution load index (PLI), which assess ecological risks, showed that samples were moderately to very highly contaminated by microfiber and could pose a threat to the aquatic ecosystem. The findings would help identify transformative challenges required for minimizing microfiber pollution from industrial sectors and improving ETP systems.

The study aimed to assess the impact of wearing protective facial masks (PFMs) on various health parameters of hospital staff amidst the COVID-19 pandemic. The aim of this study was to investigate the effects of wearing a face mask on blood oxygen saturation, heart rate, headache, fatigue, and shortness of breath in hospital staff during routine work shifts and COVID-19. In this study, participants from various clinical, administrative, and hospital cleaning professions who had at least one month of work experience were enrolled and their oxygen saturation (SpO₂), heart rate (HR), and headache were measured during routine shifts with normal daily activities. The fatigue severity scale (FSS) and the modified Borg dyspnea scale were used to assess the participants. The significance level was set at 0.05. SpO₂ and HR were lower at the end of the work shift than at the beginning (93.96 ± 1.57 vs. 95.03 ± 1.7 and 82.1 ± 11.83 vs. 83.93 ± 12.31, respectively). According to the result of the Borg scale, 59.2 % of the participants did not feel short of breath and 34.3 % had “mild-moderate” shortness of breath. The total FSS (21.46 ± 2.31) showed that the participants did not fall into the “fatigued” category. The Kruskal-Wallis test showed no significant difference in Borg score, FSS, HR, and SpO₂ participants with different mask types (P > 0.05). The result of the Kruskal-Wallis test also showed no significant difference in Borg score between the occupational groups (P = 0.073). The results showed that the frequency of pre-existing headaches had increased in 18.2 % of the respondents. The findings indicated that wearing PFMs did not have a notable impact on oxygen levels and heart rate during the regular tasks of hospital staff. However, the use of PFMs led to the development of new headaches associated with PFMs or worsened existing headaches.

Microplastic surface properties are dynamic in the environment, as weathering, primarily through photooxidation due to ultraviolet light (UV) exposure, modifies surface chemistry and surface roughness, which can affect the fate, transport and reactivity of microplastics, and therefore any potential environmental risk they may pose. This study aims to investigate and characterise the effect of different UV radiation sources that are typically used in weathering studies (UVA-340 fluorescent lamps, xenon-arc lamps and natural sunlight) on two key properties of microplastics: surface roughness and oxidation level. High- and low-density polyethylene, polypropylene and polystyrene microplastic nurdles (<5 mm) were weathered and characterised using Atomic Force Microscopy and Fourier-Transform Infrared spectroscopy. After two weeks, UVA light was found to significantly increase the carbonyl index of the subject high-density polyethylene and decrease its surface roughness. The subject low-density polyethylene was found to increase in carbonyl index when exposed to all three light sources for two weeks, and reduced in surface roughness when exposed to both xenon-arc and UVA light. Xenon-arc light increased surface roughness on the subject polypropylene after two weeks exposure. The subject polystyrene significantly increased in carbonyl index when exposed to xenon-arc light for two weeks but decreased in surface roughness when exposed to UVA light. Surface oxidation was found to be dependent on polymer type, UV source and additive content, with the data showing a relationship between surface roughness, surface shading and additive content. The results from this study highlight the complexity of microplastic weathering processes and how metrics such as carbonyl index must be applied with caution when estimating how long a plastic has been in the environment.

The major issue associated with coal mine drainage is its contribution to river pollution, which occurs at the local, regional, and global levels. The pollution of surface sediment by heavy metals is a major environmental and health concern in coal mining and downstream areas. This study explored the concentrations of eight metal components in the sediments from the Shari-Goyain River of Bangladesh. The trend of decreasing metal concentration was identified as Fe > Mn > Ni > Zn > Cu > Cr > Pb > Cd in sediment. The level of metal pollution in the study area was assessed by using various indicators like geo-accumulation index (I_geo), pollution load index (PLI), contamination factor (CF), potential ecological risk factor, and risk index (RI). The sediment in the river exhibited PLI values ranging from 0.133 to 0.543, suggesting a low level of pollution from the evaluated heavy metals (PLI < 1). The mean I_geo showed that the study area was unpolluted whereas Ni showed unpolluted to moderately polluted status. For most of the metals, the sediment samples recorded a low degree of contamination (CF < 1) except Pb, Cd, and Ni which exhibited moderate degree of contamination (1 ≤ CF < 3). Through the application of various statistical analyses, coal mine drainage has been identified as the possible source of pollution of the analyzed metals in the Shari-Goyain River. However, the risk index and RI suggested a low risk of metal pollution in the studied areas. To improve the environmental conditions of the Shari-Goyain River, it is crucial to construct permanent sediment quality monitoring stations and conduct extensive ecological investigations.

The development and widespread use of biomining are the result of the rising demand for metals. The depletion of organic resources, the abundance of low-grade metallic ores, and the vast production of metallic waste during mining and beneficiation processes have enhanced the need for biomining. Compared to high-energy-demanding and environmentally unsafe traditional mining techniques, the biomining approach is a revolutionary biotechnological technique. It is a sustainable alternative for extracting valuable metals from low-grade ores and waste materials by using microbes. Microbes have the capacity to catalyze biochemical processes, making it easier to solubilize and extract target metals from complicated mineral matrices. Notably, the redox processes, creation of organic or inorganic acids, and the release of complex agents are all necessary for biomining metals. Metal recovery is achieved from metallic grade ores, mine tailings, municipal solid waste disposal sites, incinerator ash, electronic wastes, tars, etc., all effectively processed via biomining. Biomining is also advantageous as it prevents the emission of harmful gases released from e-waste dump sites, including sulfur dioxides, nitrogen oxides, and carbon dioxide, which are of major concern. These gases may be released into the environment when open-air burning and acid baths are used for the recovery of valuable metals. Nowadays, both base metals (copper, and to a lesser extent, nickel and zinc) and precious metals (mainly gold) are extracted from ores and mineral concentrates in heaps, stirred-tank bioreactors, dumps, and other locations via microbial processing, or biomining. In the ongoing boom of the electronics industry, there is increasing pressure to handle huge amounts of electronic waste. This is also important considering the use of precious metals in the electronics sector and the need to extract them. The present review discusses biomining and bioleaching principles, methods, and also talks about e-waste in general, providing a worldwide overview. The review primarily concentrates on the use of biomining to recover valuable metals from electronic waste.

Microplastics (MPs) are an increasingly concerning type of environmental pollutant due to their abundance and the potential for bioaccumulation in aquatic food organisms. The presence of MPs in the natural waters is a clear indication of the incorrect disposal of plastic debris and the rapid growth of synthetic plastic production. An inclusive understanding of the sources, transportation, fate, and consequences of plastic waste is crucial for accurately estimating the global transit of plastic pollution and reducing its sources and hazards. Bangladesh is a significant contributor to global plastic pollution, and this review aims to summarize the existing knowledge and research gap on MP pollution in aquatic ecosystems in Bangladesh over the past five years. This article discusses the features, occurrence, and potential hazardous effects of MPs on aquatic organisms and humans to provide innovative approaches for sustainable remediation. It emphasizes the importance of a multidisciplinary approach to reducing plastic inputs into the aquatic environment, including regulation on production and consumption of plastics, using bio-based and biodegradable plastics, improving plastics life cycle, eco-friendly design for production, extended producer accountability over waste management, prioritizing recycling, creating demand for recycled plastics, and improving waste collection and management systems. The study purposes further research into plastic pollution in Bangladesh, explore environmentally friendly plastic substitutes, and provide decision-makers with effective strategies to address the plastic pollution problem in Bangladesh.