微塑料污染的水生生态毒性与载体作用

近年来微塑料的水生生态环境污染与生态毒害问题引起了科学界的广泛关注。在总结国内外相关研究的基础上，本文对水生态环境中微塑料的来源、形成与分布展开分析；对微塑料污染的生态毒性研究进展给予评述；并深入探讨了微塑料在生态系统中扮演的多重载体角色。鉴于微塑料污染的严峻现实，我国应尽快开展有关微塑料环境污染和生态毒理方面的系统研究，并辅以政策引导和经济支持。     

淡水环境中微塑料的赋存、来源和生态毒理效应研究进展

塑料制品在当今社会中被大量生产和使用,导致其不断进入水环境。环境中的塑料垃圾会进一步分解为很多粒径小于5 mm的塑料残片,即微塑料。微塑料作为一类新型污染物,已受到国内外学者和公众的广泛关注。然而,现阶段有关微塑料污染的研究主要集中在海洋环境,而内陆淡水环境与人类接触频繁,其微塑料污染应受到更多重视。为全面了解淡水环境中微塑料污染现状,加强对微塑料污染的风险监控,文章总结了近些年的相关研究,综述了淡水环境中微塑料的赋存、来源和生态毒理效应。有关研究表明,微塑料污染可能在全世界淡水环境中普遍存在,其在淡水水体、沉积物和淡水生物中均有赋存;而中国内陆淡水环境中微塑料的污染可能尤为严重。淡水环境中微塑料的来源尚不明确,主要直接来源可能包括污水处理厂的尾水排放、水环境中塑料垃圾的风化降解以及水土流失或地表径流形成的陆源输入;而初始源头可能包括了个人护理品、合成纺织品、工业原料以及城镇、农业、旅游、工业区塑料垃圾的不当处置。另外,微塑料会对淡水生物造成物理性损伤和生化水平胁迫,并有可能与其他污染物形成复合污染,对淡水生物产生交互效应。因此,对淡水环境中微塑料污染的深入研究已刻不容缓。今后可在环境因素对微塑料污染特征的影响、微塑料污染的源解析、微塑料与污染物的生态交互效应这三方面加强研究。文章可为淡水环境中微塑料的污染和生态风险研究提供理论参考。     

塑料食品包装材料的环境污染综述

塑料食品包装材料是食品包装的重要组成部分,但其与食品直接接触时易释放大量化学品和添加剂,且废弃后会分解成粒径小的微塑料,由此造成的环境污染和生态健康风险受到世界各国的广泛关注,并针对食品包装塑料中有害化学品向食品中的释放迁移过程、微塑料及其中化学品的环境污染过程等开展了大量研究.本文综述了常用塑料食品包装材料的种类、用途及其中的化学物质,详细总结了食品包装塑料自身及其中化学品的环境污染过程和生态健康毒性效应,并据此提出了塑料食品包装材料今后的控制措施及相关研究的发展方向.     

微塑料在土壤-地下水中的环境行为及其生态毒性研究进展

微塑料已成为一类新型污染物遍布全球各个角落,由此产生的环境问题日趋严峻。第二届联合国环境大会上将微塑料污染列为环境与生态科学研究领域的第二大科学问题。目前大多数研究集中在海洋环境方面,有关土壤-地下水系统中微塑料的环境行为及生态毒性相关研究还较为薄弱。本文基于大量文献调研,较系统地回顾梳理了有关土壤-地下水中微塑料的来源、迁移归趋及其生态毒理效应的研究成果,并对未来研究做出评述和展望,旨在促进土壤-地下水系统中微塑料污染的相关研究。     

土壤中微塑料污染现状与检测技术研究进展

微塑料一般是指粒径小于5 mm的塑料碎片,作为一种新污染物已经成为全球环境领域的研究热点.土壤作为环境中微塑料的最大储库,土壤中微塑料的污染逐渐引起重视并取得了一定的研究进展.本文系统了梳理了国内外土壤中微塑料的污染现状和污染特征,介绍了土壤中微塑料检测技术研究进展,重点探讨各类样品采集、前处理和和定性定量方法的优缺点以及对土壤中微塑料检测的适用性,分析了土壤中微塑料检测技术研究面临的主要挑战,提出未来土壤中微塑料污染调查与检测技术的研究方向,以期为科学开展土壤中微塑料污染风险治理与管控提供技术支撑.     

水环境中的微塑料及其生态效应

塑料在日常生活中无处不在,随意丢弃的塑料会在各种作用下最终进入江河、湖泊、近海、深海、以及大洋甚至极地地区。在外界条件(如高温、风化、紫外线)影响下,大型塑料结构的完整性易遭到破坏而被逐渐分解成微小的塑料碎片,当其粒径小于5 mm时即可被称为微塑料。塑料中的某些添加剂,如壬基苯酚、多溴联苯醚、邻苯二甲酸盐、双酚A等会在塑料降解为微塑料的过程中释放到水环境中,从而威胁到水生生态系统的安全。微塑料粒径小,易被浮游动物误食或沿着食物链传递,在生物体内累积转移,对机体产生不可逆转的毒害作用。此外,微塑料还能作为某些污染物富集的载体,产生较强的复合毒性。因此水环境正面临着微塑料污染的威胁,如何治理已成为全球性的环境问题。本文对水环境中微塑料的来源与分布、微塑料的迁移和转化以及微塑料对水环境的影响进行了综述,并对水环境中的微塑料污染问题提出了一些解决方案,期望能为微塑料及其在水环境中的生态效应研究提供理论基础和数据支持。     

水体及沉积物微塑料污染对近海养殖海区的生态风险

微塑料在全球海洋水体及沉积物中广泛存在,然而关于近海养殖海区的微塑料污染特征鲜有报道,本研究调查了中国近海养殖海区茅尾海水体和沉积物中微塑料的分布特征并初步对其微塑料污染进行风险评估.结果表明,茅尾海区域广泛分布着微塑料,茅尾海水体中微塑料的平均丰度为(2.01±1.23) n·m^-3,泡沫(60.1%)是主要的类型.沉积物中的微塑料平均丰度为(22.4±19.6) n·kg^-1,薄片(50%—100%)在采样点中占主要部分.茅尾海水体、沉积物中的微塑料粒径都以1—5 mm为主(33.3%—100%),水体和沉积物中的微塑料主要来自钦江的输入、旅游活动以及海水养殖活动.通过风险评估模型初步得出,茅尾海区域微塑料的污染水平属于中等偏低水平,水体中微塑料整体污染风险等级显著高于沉积物,生态风险等级分别属于Ⅲ级(较高风险)和Ⅱ级(较低风险).风险指数最高的点位于茅尾海入海河流钦江入海处,达到了Ⅳ级(高风险),各沉积物采样点的风险等级主要集中在Ⅰ—Ⅱ级,属于较低风险.危害评分高的聚合物聚丙烯腈(Polyacrylonitrile,PAN)是水体中微塑...     

应用物种敏感性分布评估微(纳米)塑料对水生生物的生态风险

水环境中的微(纳米)塑料对水生生物具有潜在的危害。为了评估微(纳米)塑料对水生生物的毒性效应及生态风险,本研究在广泛查阅并分析微(纳米)塑料相关毒理学研究数据的基础上,利用物种敏感性分布(Species Sensitivity Distributions,SSD)方法对其中5门10科11种水生生物的急性毒理数据进行曲线拟合;计算对应的5%危害浓度(the hazardous concentration for 5%of the species, HC_5)和潜在影响比例(potential affected fractions, PAF);计算了相应的急性生态效应阀值(predicted no effect concentration, PNEC_(acute)),并比较了各类水生生物对微(纳米)塑料的敏感性及其所受生态风险。结果表明,目前已有数据中微(纳米)塑料对费氏弧菌(Vibrio fischeri)的生态风险最大,对朱氏四爿藻(Tetraselmis chuii)的生态风险最小;基于Reweibull模型对水生生物数据所推导的PNEC_(acute)为0.185μg·L~(-1),约为当前微(纳米)塑料在水体环境中浓度的30%。利用SSD来预测微(纳米)塑料不同暴露浓度下对水生生物的PAF,发现当微(纳米)塑料暴露浓度小于10μg·L~(-1)时,水生生物所受的影响在可接受范围内;当暴露浓度达到1 000μg·L~(-1)时,将有26%的物种受到微(纳米)塑料的危害。此外,利用Rurrlioz软件估算了世界典型淡水与海水水域表层水体中微塑料对水生生物的PAF值,发现其PAF预测值都为0;将各水域微塑料浓度与急性生态效应阀值PNEC_(acute)比较后发现,除太湖外,其他水体环境中微塑料浓度都低于PNEC_(acute),说明如果只考虑微塑料本身的影响,目前世界典型水域表层水中微塑料对水生生物的危害程度大部分都在可接受的范围之内。     

渤海环境污染现状及研究进展

近十几年来,在人类活动和全球气候变化多重压力下,渤海的环境污染越来越严重,并导致了海水富营养化加剧、赤潮频发、低氧增多等一系列的生态环境灾害,备受科研工作者的关注.本文综述了传统污染物（包括营养盐、重金属、有机氯农药、多环芳烃和多氯联苯）和新污染物（包括阻燃剂、抗生素、全氟烷基化合物和微塑料）在渤海中的污染现状及其在海洋生物中的潜在生态风险状况;同时也介绍了渤海主要的生态环境问题及其特点;最后结合研究过程中发现的问题提出了几点未来研究的重点方向.旨在为打赢“十四五”期间渤海重点海域攻坚战提供参考和理论基础.     

全球微塑料研究现状及热点可视化剖析

为探究微塑料的研究现状、热点及研究趋势,本文以Web of Science核心数据库和中国知网数据库作为数据源,使用VOSviewer和CiteSpace软件对2004—2019年的微塑料领域研究文献进行关键词聚类和突现分析.结果表明,微塑料的国际研究热点主要集中在“微塑料的生物毒性作用”、“微塑料在水环境中的分布与丰度”、“微塑料的迁移和鉴定方法”、“微塑料的吸附作用”和“微塑料的归趋和降解行为”等5个方面. 2017年后外文文献的主要突现关键词为“地中海”、“空间分布”等,表明当前微塑料的国际研究趋势是探究微塑料在封闭或者半封闭的海域（主要是地中海）中的空间分布及其在底栖生物中的污染现状和生态毒性效应. 2019年中文文献共现较强的关键词主要为“检测方法”、“空间分布”、“控制对策”、“土壤生态系统”和“鄱阳湖”等,表明当前我国微塑料的研究热点可以概括为微塑料在环境（土壤和淡水）中的分布特征、鉴定和量化技术及其防控措施.未来的研究还需要完善微塑料毒性的测定方法,建立微塑料检测的标准体系并制定微塑料污染控制对策.     

A critical review of the emerging research on the detection and assessment of microplastics pollution in the coastal,marine, and urban Bangladesh

● Coastal and marine regions are the most studied for microplastic pollution. ● Tourism is a major cause of microplastic pollution in coastal regions. ● Sediments contain larger microplastics while fish ingest smaller microplastics. ● Inland lakes, rivers, and freshwater fish are impacted by microplastic pollution. ● Microplastics are found in edible salts, however, presence is less in refined salt. The research on the extent and effects of microplastics pollution in the Global South is only getting started. Bangladesh is a South Asian country with one of the fastest growing economies in the world, however, such exponential economic growth has also increased the pollution threats to its natural and urban environment. In this paper, we reviewed the recent primary research on the assessment of the extent of microplastics pollution in Bangladesh. From the online databases, we developed a compilation of emerging research articles that detected and quantified microplastics in different coastal, marine, and urban environments in Bangladesh. Most of the studies focused on the coastal environment (e.g., beach sediment) and marine fish, while limited data were available for the urban environment. We also discussed the relationship of the type of anthropogenic activities with the observed microplastic pollution. The Cox’s Bazar sea beach in south-east Bangladesh experienced microplastics pollution due to tourism activities, while fishing and other anthropogenic activities led to microplastics pollution in the Bay of Bengal. While microplastics larger than 1 mm were prevalent in the beach sediments, smaller microplastics with size below 0.5 mm were prevalent in marine fish samples. Moreover, the differences in microplastic abundance, size, shape, color, and polymer type found were depended on the sampling sites and relevant anthropogenic activities. It is imperative to identify major sources of microplastics pollution in both natural and urban environment, determine potential environmental and human health effects, and develop mitigating and prevention strategies for reducing microplastics pollution.     

Understanding and addressing the environmental risk of microplastics

Over the past decades, the plastic production has been dramatically increased. Indeed, a category of small plastic particles mainly with the shapes of fragments, fibers, or spheres, called microplastics (particles smaller than 5 mm) and nanoplastics (particles smaller than 1 μm) have attracted particular attention. Because of its wide distribution in the environment and potential adverse effects to animal and human, microplastic pollution has been reported as a serious environment problem receiving increased attention in recent years. As one of the commonly detected emerging contaminants in the environment, recent evidence indicates that the concentration of microplastics show an increasing trend, for the reason that up to 12.7 million metric tons of plastic litter is released into aquatic environment from land-based sources each year. Furthermore, microplastic exposure levels of model organisms in laboratory studies are usually several orders of magnitude higher than those found in environment, and the microplastics exposure conditions are also different with those observed in the environment. Additionally, the detection of microplastics in feces indicates that they can be excreted out of the bodies of animal and human. Hence, great uncertainties might exist in microplastics exposure and health risk assessment based on current studies, which might be exaggerated. Policies reduce microplastic emission sources and hence minimize their environmental risks are determined. To promote the above policies, we must first overcome the technical obstacles of detecting microplastics in various samples.     

Microplastics in municipal wastewater treatment plants: a case study of Denizli/Turkey

● High amounts of microplastics are released to receiving media from WWTPs. ● The effect of classical treatment processes on MP removal is important. ● MP load in the effluent of WWTPs is important for developing treatment technology. ● Additional physical treatment could help further reduce MP discharge. Plastic particles smaller than 5 mm are microplastics. They are among the significant pollutants that recently attracted attention. Great quantities of microplastics enter the sewage system daily and reach wastewater treatment plants (WWTPs). As a result, WWTPs are potential microplastic sources. Hence, they create a pathway for microplastics to reach aquatic environments with treated wastewater discharge. Studies on microplastic characterization in WWTPs have gained momentum in academia. This study investigates the abundance, size, shape, color, polymer type, and removal efficiencies of microplastics in a municipal wastewater treatment plant (WWTP) in Denizli/Turkey. The results showed that the dominant microplastic shape in wastewater samples was fibers (41.78%–60.77%) in the 100–500 µm (58.57%–80.07%) size range. Most of the microplastics were transparent-white (32.86%–58.93%). The dominant polymer types were polyethylene (54.05%) and polyethylene vinyl acetate (37.84%) in raw wastewater. Furthermore, the microplastic removal efficiencies of the Denizli Central WWTP as a whole and for individual treatment units were evaluated. Although the microplastic pollution removal efficiency of the Denizli Central WWTP was over 95%, the microplastic concentration discharged daily into the receiving environment was considerably high (1.28 × 10¹⁰ MP/d). Thus, Denizli Central WWTP effluents result in a high volume of emissions in terms of microplastic pollution with a significant daily discharge to the Çürüksu Stream.     

Microplastic sources,formation, toxicity and remediation: a review

Microplastic pollution is becoming a major issue for human health due to the recent discovery of microplastics in most ecosystems. Here, we review the sources, formation, occurrence, toxicity and remediation methods of microplastics. We distinguish ocean-based and land-based sources of microplastics. Microplastics have been found in biological samples such as faeces, sputum, saliva, blood and placenta. Cancer, intestinal, pulmonary, cardiovascular, infectious and inflammatory diseases are induced or mediated by microplastics. Microplastic exposure during pregnancy and maternal period is also discussed. Remediation methods include coagulation, membrane bioreactors, sand filtration, adsorption, photocatalytic degradation, electrocoagulation and magnetic separation. Control strategies comprise reducing plastic usage, behavioural change, and using biodegradable plastics. Global plastic production has risen dramatically over the past 70 years to reach 359 million tonnes. China is the world's top producer, contributing 17.5% to global production, while Turkey generates the most plastic waste in the Mediterranean region, at 144 tonnes per day. Microplastics comprise 75% of marine waste, with land-based sources responsible for 80–90% of pollution, while ocean-based sources account for only 10–20%. Microplastics induce toxic effects on humans and animals, such as cytotoxicity, immune response, oxidative stress, barrier attributes, and genotoxicity, even at minimal dosages of 10 μg/mL. Ingestion of microplastics by marine animals results in alterations in gastrointestinal tract physiology, immune system depression, oxidative stress, cytotoxicity, differential gene expression, and growth inhibition. Furthermore, bioaccumulation of microplastics in the tissues of aquatic organisms can have adverse effects on the aquatic ecosystem, with potential transmission of microplastics to humans and birds. Changing individual behaviours and governmental actions, such as implementing bans, taxes, or pricing on plastic carrier bags, has significantly reduced plastic consumption to 8–85% in various countries worldwide. The microplastic minimisation approach follows an upside-down pyramid, starting with prevention, followed by reducing, reusing, recycling, recovering, and ending with disposal as the least preferable option.

     

微塑料与农药污染的联合毒性作用研究进展

近海环境中的微塑料污染问题已成为全球性的环境问题,引起了世界范围内的广泛关注。微塑料不仅能够对生物造成物理损伤,而且塑料中的添加剂如邻苯二甲酸酯、双酚A、多溴二苯醚等也会随着塑料的风化而浸出进入环境,对生物产生毒害,同时,微塑料还能吸附海洋环境中的其他污染物,从而对生物产生联合毒性作用。本文综述了微塑料与持久性有机污染物的联合作用,结果表明聚苯乙烯微塑料能够吸附海水中的持久性有机污染物如多环芳烃、多氯联苯、有机氯农药滴滴涕,从而可能导致这些污染物在海洋生物组织中富集,对人类健康存在直接或间接危害。最后本文在总结前人研究的基础上,对未来微塑料与农药污染联合毒性作用的研究方向做了简要分析和展望。     

Accumulation and fate of microplastics in soils after application of biosolids on land: A review

Environmental Chemistry Letters - The recent discovery of microplastic occurrence in most ecosystems is raising health concerns globally, yet the fate of microplastics is poorly known, particularly...     

Quantitative analysis of microplastics in coastal tidal-flat reclamation in Dongtai,China

• Reclamation projects are important disturbances on microplastic risk in coasts. • Tidal-flat reclamation area is a large storage medium for sedimentary microplastics. • Aging and distribution features of soil microplastics show spatial heterogeneity. • Coastal weathered engineering geotextiles are a significant threat to marine health. Coastal tidal flats have received considerable attention in recent years, as they provide a direct channel for the discharge of terrestrial microplastics into the ocean. Land reclamation is occurring increasingly frequently in coastal tidal-flats; however, the environmental impacts of these activities remain unclear. Therefore, this pioneering study assessed the microplastic emission characteristics of reclamation geotextiles and performed a risk assessment accordingly. Morphological characterization of geotextile samples collected from five sites in Dongtai, China, provided evidence of sedimentary weathering. Based on several assumptions, the average abundance of microplastics in soil covered by geotextiles was estimated to reach 349±137 particles/kg dry weight, with the total microplastic load in the reclaimed area estimated to be 20.67±8.06 t. Compared with previous studies, this research demonstrates that coastal reclamation areas store a high concentration of microplastics, aggravating marine microplastic pollution. Moreover, conditional fragmentation model results revealed that the weathering and distribution characteristics of soil microplastics in coastal tidal-flat areas exhibit spatial heterogeneity, being more easily affected by natural factors (such as tides) than those in inland areas. As a result of tides, the annual discharge of geotextile-originating microplastics from the studied areas into the ocean was approximately 2465.52±960.77 t. These findings prove that the risks posed by engineering-microplastics are significant, indicating that further investigations are required on the precise laws of transfer and migration, as well as the toxicity mechanisms, in order to improve analytical techniques and policies in this field.