Current Pollution Reports最新文献

Purpose of Review

As short-chain chlorinated paraffins (SCCPs) have been classified as persistent organic pollutants (POPs), there has been a significant surge in the utilization of medium- and long-chain chlorinated paraffins (MCCPs and LCCPs) as potential alternatives. However, their environmental and ecological risks have gained more prominence. Consequently, the objective of this review is to provide a comprehensive overview of the biological effects, migration, and transformation of chlorinated paraffins (CPs), with a particular focus on comparing the similarities and differences among SCCPs, MCCPs, and LCCPs.

Recent Findings

According to the latest research findings, it has been discovered that MCCPs and LCCPs possess persistence, bioaccumulation, and long-distance migration abilities, similar to SCCPs. Moreover, these research results demonstrate that the toxicity of MCCPs and LCCPs, especially those components with high chlorine content, is equally significant as that of SCCPs. Furthermore, MCCPs and LCCPs in the environment can undergo biotransformation and photodegradation processes, resulting in the generation of toxic substances such as very short-chain chlorinated paraffins (vSCCPs), SCCPs, and chlorinated alcohols.

Summary

This review comprehensively examines the biological toxicity, health risks, migration, and transformation of CPs with different chain lengths. In addition, the study analyzes the sources and trends of vSCCPs, SCCPs, MCCPs, and LCCPs in different environment media. It should be noted that SCCPs pose a greater health risk to aquatic organisms, whereas MCCPs are particularly concerning for infants. On the other hand, LCCPs present a higher health risk to terrestrial organisms, especially those situated at the top of the food chain. Based on the drawbacks of current research, outlook for future research was proposed. This review is expected to provide a reference for more scientific and reasonable evaluation of the CPs environment risk.

Purpose of Review

Lignocellulosic biomass, as a green and sustainable resource, can be used in biorefineries to produce bio-based products. The complex and resistant structure of lignocellulose prevents microorganisms access to carbohydrates in the biorefinery’s main processes, necessitating pretreatment. Different conventional pretreatment methods (physical, physico-chemical, chemical, and biological methods) and also novel advanced oxidation processes (AOPs) and their sustainability, environmental impact, economic viability, energy efficiency and, commercialization state are investigated in this review.

Recent Findings

Due to various reviews and studies on conventional pretreatment methods, they are briefly described with proper data. As the mechanisms and principle of operation of AOPs were investigated, during the AOPs pretreatment methods, hydroxyl radicals (·OH) are generated sufficiently to decompose lignocellulosic structure through oxidation. In this paper, we review the different AOPs, i.e., Fenton process, ozonation, photochemical, wet air oxidation, ultrasound, and electrochemical, which are recently used in the pretreatment of lignocellulose. Also, the achievement of different AOPs pretreatment research studies and general trends governing the process operating conditions are presented briefly in tables. Moreover, lignocellulosic biomass pretreatment sustainability assessment approaches such as life cycle assessment (LCA) and economic value and environmental impact (EVEI) are discussed. Although no study compared the sustainability aspects of different AOPs with conventional methods, this review generally addresses them. Further, environmental, energetic, and economic aspects of AOPs methods have been compared as important criteria in selecting a pretreatment method.

Summary

This review provides a thorough insight into the biorefinery’s bottleneck, pretreatment, and comprehensively investigated mechanisms, principle of operation, sustainability, environmental, economic, energy, and commercialization state of AOPs methods.

Purpose of Review

This review intends to recapitulate the pretreatment measures of kitchen waste and kitchen wastewater (KWAKWW). Furthermore, this review also separately summarizes the ascendancy of using bacteria, microalgae and microalgae-bacteria consortia to treat KWAKWW, and corresponding emerging reinforcement strategies.

Recent Findings

Tremendous amount of KWAKWW are annually generated in the whole world. Wherein roughly 1.3 billion tons of kitchen waste (KW) are dumped and which were forecasted that would increase to about 2.5 billion tons by 2025. In addition, KWAKWW have the characteristics of high content of refractory organic matter (e.g., oil and cellulose), water (commonly outstrip 70%), and salt, which is difficult for bacteria or microalgae to treat. Consequently, it is essential to perform efficacious pretreatment measures to boost the efficiency of post-treatment. Utilizing bacteria, microalgae, and microalgae-bacteria consortia to treat KWAKWW is considered an efficient strategy due to ascendancy of puissant deep purification ability, excellent resource appreciation effect, and low operation costs. For instance, bacteria could produce leastways four kinds of products through KWAKWW; multiple studies indicated that microalgae generally could remove exceed 70% of nutrients of KWAKWW; one research manifested that microalgae-bacteria consortia retrenched 46% of the demand about dissolved oxygen (DO). Nevertheless, the above microbial treatment systems still have some inherent drawbacks such as poor impact resistance. Fortunately, metabolic engineering and other strengthen strategies can efficaciously upgrade the nutrient removal and resource utilization performance of bacteria, microalgae, and microalgae-bacteria consortia. For example, one research shown that the 1-butanol productivity of original bacteria remarkably increased by 93.48–171.74% draw support from metabolic engineering.

Summary

A total of 221 papers related to the content of this review were searched through Web of Science (http://apps.webofknowledge.com). What is more, specific data that emerged on this review were all extracted from the above-searched papers. The mechanisms and effect of hydrothermal carbonization (HTC) and other four pretreatment measures are introduced by this review in detail. The preponderance of utilizing bacteria, microalgae, and microalgae-bacteria consortia to treat KWAKWW are comprehensively evaluated mainly from the perspectives of nutrient purification and resource utilization. Four state-of-the-art strengthen strategies like machine learning are then introduced. Finally, the current challenges in KWAKWW treatment are summarized from five aspects, and future concrete improvement directions are also provided. Overall, this review outlines the state-of-the-art research progress of KWAKWW treatment by b

Purpose of Review

As an important type of light-absorbing aerosol in the atmosphere, brown carbon (BrC) is an effective driver for climate change. Field observations of BrC typically involve the extraction of filter samples (e.g., using water and methanol), followed by optical and chemical analyses. This review summarizes the concentration measurements, optical properties, and chemical characteristics of BrC in China, based on results from the extraction approach.

Recent Findings

We started with measurement techniques for the determination of BrC concentration and compared the extraction efficiencies of different solvents. Then we investigated the temporal and spatial variations of BrC’s absorption Ångström exponent (AAE) and mass absorption efficiency at 365 nm (MAE₃₆₅), two parameters relevant to climate studies. AAE and MAE₃₆₅ were found to be mainly influenced by the type of solvent used and BrC sources, respectively. Using the observed AAE and MAE₃₆₅, BrC was demonstrated to be a non-negligible contributor to climate forcing. Finally, BrC chromophores were discussed on a molecular level, with focus on the nitrogen-containing compounds and polycyclic aromatic hydrocarbons.

Summary

Despite studies on BrC concentrations measurements were widely conducted, standardized methods remain inconclusive. Regarding the optical properties of BrC, MAE₃₆₅ exhibited significant temporal and spatial patterns, while AAE showed the opposite results. Through chemical characterization, BrC chromophores were identified and their association with optical properties was highlighted. This review contributes to the understanding of BrC properties and has implications for future studies on BrC.

Graphical Abstract

Purpose of Review

During the past decade, weather and climate extremes, enhanced by climate change trends, have received tremendous attention because of their significant impacts on socio-economy, public health, and ecosystems. At the same time, many parts of the world still suffer from severe air pollution issues. However, whether and how air pollutants play a role in weather and climate systems through complex interactions and feedbacks with meteorology and ecosystems remains an open question. So far, only a relatively small number of studies have been conducted to understand and quantify air pollution interactions with weather and climate extremes. As a result, there is limited process-level knowledge of this topic and associated mechanisms. This review paper provides a concise synthesis of recent scientific advances, current knowledge gaps, and future directions on air pollution interactions with weather and climate extremes, such as extreme precipitation, floods, droughts, wildfires, and heat waves.

Recent Findings

There is evidence (albeit limited) that air pollution can contribute to or interact with each of the aforementioned extremes, and several possible mechanisms (e.g., physical, thermodynamical, dynamical, chemical, and ecological processes) have been identified and proposed to explain their relationships. However, there are still substantial knowledge gaps that need to be addressed in future studies, which will benefit from enhanced observational and modeling capabilities as well as interdisciplinary collaborations.

Summary

Overall, the air pollution interactions with weather and climate extremes are currently under-studied and less understood. More future research is needed for process-level investigations to improve the mechanistic understanding on this topic.

Purpose of Review

Environmental pollution stemming from industrial, agricultural, and domestic activities is constantly increasing. The removal of these hazardous pollutants from the environment is inevitable, so finding and developing convenient, cost-effective, and biocompatible treatment methods is imperative. As emerging adsorbents, green nanoparticles (NPs) have received significant attention in recent years due to their biocompatibility and promising capability for removing pollutants such as heavy metals from aqueous solutions. This study aims to provide a comprehensive and coherent review of the heavy metals removal via an adsorption technique using green nanoparticles, focusing on their synthesis and adsorption mechanisms.

Recent Findings

Currently, plants and microorganisms are used to synthesize green nano-adsorbents. The antioxidant compounds in the extracts of different parts of the plants could be used as reducing agents for the synthesis of zero-valent metal nanoparticles. Moreover, they can be applied to the surface of nanoparticles, which enhances the stability of synthesized nanoparticles. In addition to plant-derived compounds, microorganisms can play a significant role in synthesizing green nanoparticles.

Summary

For decades, human health and the environment have been threatened by exposure to heavy metals caused by the activities of mines, industries, and factories. Therefore, there is a need to provide solutions to remove these pollutants from the environment. One of the effective solutions is the adsorption method. The efficiency of this method is strongly influenced by the selection of suitable adsorbents. In recent years, special attention has been paid to nano-adsorbents. Utilizing green nano-adsorbents, as opposed to conventional materials, is a critical strategy for reducing environmental pollutants, particularly for heavy metal adsorption from contaminated water and wastewater. This paper also discusses the sources and occurrence of heavy metals, as well as a number of environmental issues of methods that employ green and eco-friendly nano-adsorbents for heavy metals removal, including (i) the type of heavy metals and their use pattern, (ii) influencing factors, (iii) heavy metal analysis methods and their potential toxicity, and (iv) different conventional and cutting-edge nanotechnologies for water and wastewater treatment. The literature review, which covered the years 2002–2023, provided a critical illustration of current concerns about heavy metal contamination and removal efforts, with a focus on green nano-adsorbents and the use of these environmentally friendly materials.

Purpose of Review

Growing algae in wastewater offers carbon-neutral biomass production and pollutant removal. However, practical applications of wastewater-grown algal biomass have social acceptability issues in the food and feed industries due to unexpected threats (such as human/animal pathogens and toxins) associated with the wastewater-grown biomass. Therefore, considering the substantial pollutant removal potential of microalgae and the abundance of wastewater as a growth media, alternative bioprocessing routes of the wastewater-grown biomass should be developed. This review highlights some non-food and non-feed applications of wastewater-grown algae biomass.

Recent Findings

Wastewater-grown algal biomass contains high amounts of carbohydrates, proteins, and lipids depending upon the composition of wastewater and algal species grown. These three significant metabolites are precursors to bioenergy and biomaterial products such as bioethanol, biogas, and bioplastics. Hydrolysis of the wastewater-grown algal biomass can be easily improved to enhance the microbial fermentation yields to produce bioethanol and biobutanol. Fresh algal biomass, residual biomass, or both can be used as feedstocks in anaerobic digestion/co-digestion to produce biogas. Depending upon the selected species, wastewater-grown algal biomass can also produce biopolymers whose productivity depends on growth conditions, wastewater composition, and biopolymer synthesis method. Enzymatic, eco-friendly chemicals and mechanical approaches used to prepare biopolymers from algal biomass should be optimized for higher yields of biopolymers.

Summary

Although wastewater-grown biomass has acceptability issues, it offers certain environmental benefits, including atmospheric carbon capture, phycoremediation of pollutants, and water recycling. This manuscript highlights the recent progress and emerging trends of wastewater-grown algal biomass as a feedstock with potential applications for fermentation, anaerobic digestion, and bioprocessing to produce clean energy and bioplastics.

Graphical Abstract

Purpose of Review

Calculating atmospheric aerosol radiative forcing is a crucial aspect of climate change research. The aerosol scattering phase function stands out as a vital parameter for radiative forcing computations and holds significant importance in the remote sensing retrievals of aerosols. Despite its significance, research on aerosol scattering phase function measurements has been limited over the years. This review article provides a comprehensive summary of relevant studies on the measurements of aerosol scattering phase functions.

Recent Findings

In recent times, the application of imaging detection techniques in the measurement of aerosol scattering phase functions has emerged, highlighting advantages such as portability and high temporal-angular resolution. In addition, the development of aerosol retrieval algorithms facilitates a broader application of the results obtained from aerosol scattering phase function measurements in estimating aerosol physical properties and satellite retrievals.

Summary

This review introduces the measurement techniques, instruments, and retrieval algorithms associated with aerosol scattering phase functions, encompassing laboratory experiments, in situ field measurements, and remote sensing retrieval. The measurement results and related research on aerosol morphological effects and physical property retrievals have been summarized. Finally, it outlines future research prospects, suggesting improvements in instruments, experimental expansion, and enhanced data analysis and application, providing feasible suggestions for further studies.

Purpose of Review

Rapid economic development accompanied by urbanization, motorization, and industrialization, together with population growth, puts great pressure on the power sector in Southeast Asia (SEA) to meet energy demand. This paper reviews the past 20-year power generation in SEA countries to analyze potential impacts on atmospheric pollution using DPSIR framework.

Recent Findings

In 2020, total region electricity generation reached 1050 TWh, 3.1 times above that of 2000, and is projected to further increase by 2.5 times in 2050. During the period, the annual per capita generation increased 2.4 times. Indonesia, Malaysia, Thailand, and Vietnam were the main electricity producers, sharing 83% in 2020. Coal and natural gas based thermal power plants (TPPs) were dominant with 72% of the total electricity produced, whereas low-carbon renewable energy, although increased during the period, shared only 25% in 2020. In 2018, the sectoral atmospheric emissions of different species increased by 2.4–11.5 times above 2000, contributing 55.3%, 26.8%, and 26.7% to the region’s total anthropogenic emissions of SO₂, CO₂, and NO_x, respectively.

Summary

Heavy reliance on fossil fuels makes the power sector a key emission source of air pollutants and greenhouse gases. SEA governments have promulgated policies and regulations for TPPs and set net zero emissions targets. These policies, directly and/or indirectly address atmospheric pollution, once fully implemented, bring in more secure and sustainable power sources in the region, along with multiple benefits to air quality, human health, environment, ecosystem, and the climate.