Current Pollution Reports最新文献

Purpose of Review

Triclosan (TCS), a widely used broad-spectrum antimicrobial agent, enters to wastewater treatment plants (WWTPs) and the environment ultimately after its usage. Notably, the use of TCS has surged during the outbreak of COVID-19, leading to the environment under increasing TCS pollution pressure. Even environmentally relevant concentrations of TCS can promote the development of antimicrobial resistance (AMR), which is a major public health concern. The purpose of this study is to provide a basis for the management and risk assessment of TCS by providing a holistic review of the impact of TCS on AMR in the environment.

Recent Findings

Bacterial resistance to TCS mainly takes place through modification or replacement of the FabI enzyme, which is the main target of TCS in bacteria. Currently, multiple FabI mutants and isoenzymes have been identified in the environment giving bacterial resistance to TCS. In addition, mechanisms by which TCS promotes bacterial development of resistance to other antimicrobials have been studied in laboratory experiments and environmental settings, such as anaerobic digester. TCS will promote the development of AMR in the environment with the possibility of adverse risks to public health.

Summary

This review systematically summarizes the mechanisms of bacterial resistance to antimicrobials driven by TCS and highlights the effects of TCS in promoting the horizontal transfer and enrichment of antibiotic resistance genes (ARGs). Suggestions for overcoming the limitations of laboratory-scale studies and further improving the risk assessment of TCS in the environment are proposed.

Building ventilation rate is a crucial factor in the indoor air quality (IAQ). Furthermore, building-related parameters (window geometry, building orientation, height, and shape) have a substantial impact on the ventilation rates. However, most building designs reported in the literature from various income group countries failed to fulfill the recommended ventilation standards. A systematic and critical review was conducted on the collated literature from the past 20 years using various databases, yielding 145 related articles. Building-related factors influencing the ventilation rates were thoroughly studied in different income groups. In addition, the existing ventilation rates in various building environments were examined. The data analysis of critical literature suggests that the ventilation rates in 80% of the building environments were found lower than the prescribed standards irrespective of the income group countries. Thus, the current study highlights the need for redesign of the existing or new buildings for meeting the adequate ventilation rates.

Numerous epidemiological and toxicological studies have demonstrated the important role of secondary organic aerosol (SOA) in PM_2.5-related adverse health effects. Primary organic aerosol, volatile organic compounds (VOCs), and intermediate volatile organic compounds (IVOCs) can react with multiple atmospheric oxidants (e.g., NO_x and free radicals) and generate SOA. The chemical composition of SOA varies with precursor identity and aging conditions; however, knowledge regarding their transformation process and mechanisms and associated toxicity remains to be explored. Herein, this review systematically summarizes the chemical and toxicological transformations of different types of organic aerosols, i.e., fresh aerosols from different sources and representative precursors with different structures. Atmospheric aging generally enhances the toxicity of organic aerosol. Specifically, aged aerosols from biomass combustion and traffic emissions are more toxic than those from coal combustion, cooking, and biogenic sources, which might be attributable to their different precursor compositions. For certain precursors, aromatic compound-derived SOA always has the highest oxidative stress and toxicity, followed by unsaturated alkene and saturated alkane-derived SOA, which might be related with their different oxidation products. Furthermore, we describe the current research progress on the effects of major redox reactants involved in the aging process. The toxicity of SOA is complexly affected by the species and contents of atmospheric redox reactants, including ³C*(organic triplet oxidation state), NO_x, and transition metal ions. This work is expected to provide a promising perspective for a better understanding of the toxicity profile of SOA and regulation of hazardous SOA pollution.

Purpose of Review

Rather than broadly investigating the beamforming field, the present work has the distinctive feature of analyzing the most common algorithms through both a theoretical presentation and a report of their most recent applications to real cases. The intent is to take a step forward towards the harmonization of the sector with a combined approach that could prove to be useful for academics willing to understand the theory and for technicians needing to choose the best algorithms to use in different measurement conditions.

Recent Findings

In recent years, the sector has seen the growth of studies published on the use of beamforming techniques and their applications to real cases. Unfortunately, different authors and research groups developed so many different algorithms that a literature review turns out to be essential to increase awareness and to avoid confusion for both scientists and technicians.

Summary

Nowadays, acoustic cameras have been proven to be powerful instruments that combine a video acquisition with a microphone array to obtain real-time information about the location of noise sources. Different beamforming techniques can be applied to sound signals allowing their visualization or distinguishing the contribution of multiple different emitters. This quality, historically used in different branches of acoustics, is now spreading into environmental noise protection, especially where it is needed to locate the emitters or to better study sources that have not yet been characterized. Acoustic cameras can also be used to identify the responsible for noise limits exceedings at receivers when traditional microphone measurements are not enough, or to identify potential leakages occurred in the installation of noise abatement measurements.

Carbon dots (CDs) or carbon quantum dots (CQDs) have emerged as rising stars in the carbon family due to their diverse applications in various fields. CDs are spherical particles with a well-distributed size of less than 10 nm. Functional CDs are promising nanomaterials with low toxicity, low cost, and enormous applications in the field of bioimaging, optoelectronics, photocatalysis, and sensing. Plastic is non-biodegradable and hazardous to the environment, however extremely durable and used in abundance. During the COVID-19 pandemic, the use of plastic waste, particularly masks, goggles, face shields, and shoe cover, has increased tremendously. It needs to be recycled in a productive way as plastic wastes take hundreds or thousands of years to degrade naturally. The conversion of plastic waste into magnificent CDs has been reported as one of the key alternatives for environmental sustainability and socio-economic benefits. In this review, synthetic routes for the conversion of plastic wastes into CDs utilizing hydrothermal, solvothermal, pyrolysis, flash joule heating, and characterization of these CDs using different techniques, such as Fourier-transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, and transmission electron microscope, have been discussed. Furthermore, potential applications of these plastic-derived CDs in sensing, catalysis, agronomics, and LED lights are summarized herein.

Purpose of Review

Annually, huge amounts of microplastics (MPs) are added to farmlands through sewage sludge (SS)/biosolid applications as a fertilizer. Most research emphasizes the enormity of the problem and demonstrates the fate, impacts, and toxicity of MPs during SS treatment processes and land applications. None has addressed the management strategies. To address the gaps, the current review evaluates the performance analysis of conventional and advanced sludge treatment methods in eliminating MPs from sludge.

Recent Findings

The review uncovers that the occurrence and characteristics of MPs in SS are highly governed by factors such as population density, speed and level of urbanization, citizens’ daily habits, and treatment units in wastewater treatment plants (WWTPs). Furthermore, conventional sludge treatment processes are ineffective in eliminating MPs from SS and are accountable for the increased small-sized MPs or micro(nano)plastics (MNPs) along with altered surface morphology facilitating more co-contaminant adsorption. Simultaneously, MPs can influence the operation of these treatment processes depending on their size, type, shape, and concentration. The review reveals that research to develop advanced technology to remove MPs efficiently from SS is still at a nascent stage.

Summary

This review provides a comprehensive analysis of MPs in the SS, by corroborating state-of-the-knowledge, on different aspects, including the global occurrence of MPs in WWTP sludge, impacts of different conventional sludge treatment processes on MPs and vice versa, and efficiency of advanced sludge treatment and upcycling technologies to eliminate MPs, which will facilitate the development of mitigation measures from the systematic and holistic level.

Graphical Abstract

Purpose of Review

Neonicotinoids are synthetic insecticides, and among all agrochemicals, they rank second in consumption. The unparalleled use of neonicotinoids in various sectors including agriculture has currently reintroduced them as emerging pollutants/hazards due to their endocrine-disrupting nature. High water solubility, low volatility, and persistent nature have resulted in their accumulation in the environment. Thus, investigating efficient and sustainable methods for the remediation of contaminated environments due to this pollutant is imperative.

Recent Findings.

Bioremediation provides a cost-effective and environment-friendly option over conventional physicochemical techniques that produce toxic byproducts. The microbial route for degradation has the potential to completely mineralize neonicotinoids by virtue of their adaptive and diverse metabolic machinery. Potent microbes such as Ensifer, Phanerochaete, Bacillus, Ochrobactrum, Trametes, Rhodococcus, Sphingobacterium, and Pseudomonas have been isolated and screened for their immense degradation potential, and the metabolites, degradative enzymes, and transformation pathways have been elucidated. The incorporation of modern tools/techniques such as metabolic engineering, microbial biotechnology, omics-based database approaches or systems biology, artificial intelligence, and machine learning can fasten and give better bioremediation results.

Summary

This study has aimed to summarize the processes employed to date to degrade neonicotinoids and present a comprehensive report reflecting past efforts, advances, and future prospects. Therefore, this report will be beneficial in strengthening the understanding of the extent of efforts made for neonicotinoid degradation and how conventional approaches such as bioaugmentation, biostimulation, and biofiltration can be accelerated by advanced technologies viz., omics and machine learning.

Purpose of Review

Microalgae-based photosynthetic algal biofuel cells (PAMFCs) are effective devices for purifying wastewater and fixing carbon, nitrogen, and phosphorus, converting light energy into electricity for integrated bioelectricity, biodiesel feedstock, and more. This paper reviewed the great potential of PAMFC for wastewater treatment and energy utilization, providing new ideas for wastewater treatment and green energy development.

Recent Findings

The concept of the PAMFC is to convert pollutants into bioelectricity by using the metabolic activity of microbial populations in the wastewater, and the microalgae at the cathode make it possible to convert solar energy into green energy. The construction and type of PAMFC, biotic and abiotic factors all have an impact on its wastewater treatment and energy production. Considering the above facts, the drawbacks of PAMFC were summarized and the future development for its application in wastewater treatment and energy use was prospected.

Summary

This paper reviewed the use of PAMFC systems to recover resources in the form of nutrients, bioelectricity, and biodiesel feedstock in wastewater treatment. The selection of reactor configuration, cathode and anode materials, electrogenic microorganisms, and system optimization conditions were analyzed. The limitations of PAMFC in terms of reactor performance and scale in practical production applications were discussed and future directions for PAMFC were proposed.

Purpose of Review

This review article focuses to fulfill the gaps in the available literature on cancer incidence, antineoplastic drug consumption, environmental persistence, and toxicity assessment and provides a better understanding of the evaluation of the risk and difficulties resulting from the emergence of anticancer medications.

Recent Findings

Large amounts of antineoplastic drugs present in water bodies have adverse effects on the environment and human health. As the number of cancer patients continues to grow exponentially, the prevalence of antineoplastic chemicals in aquatic environments is steadily increasing worldwide. The oncology wards at hospitals, pharmaceutical firms, and municipal garbage (from outpatients) are the biggest contributors to the presence of antineoplastic drugs in aquatic environments. When released into the environment, the unmetabolized fraction/derivatives and free radicals of these medicines are more toxic.

Summary

It is evident from the review that the ecotoxicity, mutagenicity, and cytotoxicity are a result of the persistence of antineoplastic drug residual in water bodies. Thus, the presence of such substances in water bodies is detrimental to the health of both aquatic species and humans. The fate of antineoplastic drugs in the environment will also cause an adverse effect on agricultural crops and the soil microflora if the treated wastewater would be used for irrigation purposes.

Purpose of Review

This study was aimed at identifying the differences in the levels of 17 metals and elements (MEs) between fish species (Capoeta tinca and Squalius pursakensis) and fish tissues (muscle, gills, and liver), at identifying the effect of fish gender and fish size (length and weight) on bioaccumulation of MEs in tissues, at assessing both health risks and benefits of MEs in fish muscle, and at defining safe fish consumption quantities for consumers.

Recent Findings

The levels of most MEs in tissues did not differ significantly between both fish species. The gills had higher levels of most MEs than the liver and muscle. Only a few MEs in the tissues of both fish species demonstrated significant associations with fish length or weight. There were no significant differences between male and female fish in terms of the levels of most metals in tissues. The estimated daily intake (EDI) values of metals were below the reference doses. Target hazard quotient (THQ) and hazard index (HI) values were less than 1. Carcinogenic risk (CR) values were within or below the acceptable range. Also, maximum safe fish consumption quantities (MSCQs) were established for consumers.

Summary

Because both fish species were collected from the same water body and had the same habitat preferences, the levels of most MEs did not differ significantly in the tissues of both fish species. Because the gills and liver are metabolically active organs, they had higher levels of MEs than the muscle. The relationships between the levels of MEs in the tissues and fish size were both unclear and inconsistent. The results indicated that ME accumulation in tissues of individuals within the same species was not significantly influenced by gender. The THQ, HI, CR, and EDI values indicated that no adverse health consequences are expected for consumers. It was established that daily consumption of less than 50 g of C. tinca or 80 g of S. pursakensis would not be harmful to consumers’ health. Nutritional evaluation results indicated that both fish species are good sources of essential MEs. Therefore, consumption of the fish species would bring tremendous health benefits.