Recycling process produces microplastics Staplevan, Michael J; Hai, Faisal I
Science (American Association for the Advancement of Science)
383, Issue:
6686
Journal Article
•Microplastic concentration is lower in catchments with less intensive urbanization.•Microplastic concentration is higher in sediments with a greater proportion of sand.•Polyethylene and ...polypropylene are the most common polymers in stormwater drains.
Microplastics (MPs) are small plastic pieces with size less than 5 mm that have entered and polluted the environment. While many investigations including several critical reviews on MPs in the ...environment have been conducted, most of them are focused on their occurrences in marine environment. Current understanding on the occurrences, behaviors, and impacts of MPs in the terrestrial environment is far from complete. A systematic review of the literature was thus conducted to promote the research on MPs in the environment. This work is designed to provide a comprehensive overview that summarizes current knowledge and research findings on environmental occurrences, fate and transport, and impacts of MPs. In addition to discussing the occurrences, characteristics, and sources of MPs in the ocean, freshwater, sediments, soils, and atmosphere, the review also summarizes both the experimental and modeling data of the environmental fate and transport of MPs. Research findings on the toxic effects, bioaccumulation, and bioavailability of MPs in the environment are also covered in this critical review. Future perspectives are discussed as well.
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•Occurrences, characteristics, and sources of MPs in various environmental media are reviewed.•Experimental and modeling data of the environmental fate and transport of MPs are summarized.•Toxic effects, bioaccumulation, and bioavailability of MPs in the environment are discussed.•Existing knowledge gaps and future research directions are discussed.
Given the global abundance and environmental persistence, exposure of humans and (aquatic) animals to micro- and nanoplastics is unavoidable. Current evidence indicates that micro- and nanoplastics ...can be taken up by aquatic organism as well as by mammals. Upon uptake, micro- and nanoplastics can reach the brain, although there is limited information regarding the number of particles that reaches the brain and the potential neurotoxicity of these small plastic particles.Earlier studies indicated that metal and metal-oxide nanoparticles, such as gold (Au) and titanium dioxide (TiO
) nanoparticles, can also reach the brain to exert a range of neurotoxic effects. Given the similarities between these chemically inert metal(oxide) nanoparticles and plastic particles, this review aims to provide an overview of the reported neurotoxic effects of micro- and nanoplastics in different species and in vitro. The combined data, although fragmentary, indicate that exposure to micro- and nanoplastics can induce oxidative stress, potentially resulting in cellular damage and an increased vulnerability to develop neuronal disorders. Additionally, exposure to micro- and nanoplastics can result in inhibition of acetylcholinesterase activity and altered neurotransmitter levels, which both may contribute to the reported behavioral changes.Currently, a systematic comparison of the neurotoxic effects of different particle types, shapes, sizes at different exposure concentrations and durations is lacking, but urgently needed to further elucidate the neurotoxic hazard and risk of exposure to micro- and nanoplastics.
Microplastic (MP) pollution is a raising global concern in recent years due to its wide distribution. Additionally, most of the MPs have undergone extensive weathering in the environment, and ...weathered MPs may exhibit different physicochemical properties from pristine ones. The review reveals the change in physicochemical properties (e.g. size, color, crystallinity, mechanical property and oxygen-containing groups) and the release of additives and MP-derived intermediates (i.e. oligomers and oxygenated compounds) during weathering processes. Weathering further affects the sorption behavior of MPs for environmental pollutants because of the changed crystallinity, specific surface area and oxygen functional groups. The interaction mechanisms of pristine and weathered MPs with pollutants are summarized, and how weathering processes affect sorption behavior is critically revealed. Because of the changed size, color and surface charges, weathered MPs might be ingested by aquatic organisms in different ways from the pristine ones. The detailed effects of weathering on the ingestion of MPs are discussed, and the potential toxicity of leachates from weathering processes is evaluated. In addition, the environmental components (e.g. natural organic matter and salinity) and biofilm correlated to the sorption behavior of MPs are reviewed. As for the knowledge gap, further studies should focus on the long-term weathering of MPs and the relationships between weathering properties and sorption capacities toward pollutants. The potential risks of weathered MPs and leachates on organisms should be explored.
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•Weathering significantly changes the physicochemical properties of microplastics.•Surface area, oxygen groups and crystallinity critically affect sorption of pollutants.•Effects of weathering on the risks of microplastics and leachates are revealed.•NOM, salinity and biofilms involved in the environmental behavior are reviewed.
This study involved an assessment of the levels of microplastic pollution in seven small-scale estuaries in Shanghai for the first time. The abundance of microplastics ranged from 13.53 ± 4.6 to ...44.93 ± 9.41 particles L−1, with a mean abundance of 27.84 ± 11.81 particles L−1. Microplastics collected from samples were classified into four types (fiber, film, granule, and fragment), and granules were the most abundant type. Up to 99.5% of microplastics were <2 mm in diameter. The microplastics had a variety of colors, with black being the dominant color. Polypropylene (37.5%) and polyethylene (50%) were the main types of microplastic component validated. Our study showed severe microplastic pollution in small-scale estuaries, and the associated rivers need urgent attention for microplastic pollution prevention.
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•The high microplastic abundances were found in small-scale estuaries of Shanghai.•Granular, black and diminutive were the main features of the found microplastics.•Management strategies over microplastics were put forward for Chinese contexts.
Microplastic pollution in marine waters around the globe is increasing exponentially. This is the first comprehensive review which focuses on microplastics as a source and vector for metals, ...antibiotics, toxic chemicals, pathogenic bacteria (Vibrio cholerae), and Harmful Algal Bloom (HAB)-forming dinoflagellates across the continents through ballast water. Microplastics in ballast waters serve as ‘hotspots’ for the development and spread of multiple drug-resistant human pathogens through co-selection mechanisms. Microplastic inoculation at distant countries through ballast water may pose a serious threat to human health due to higher incidences of bacterial disease outbreaks and HABs. The 2017 ballast water management convention lacks a provision for on-board treatment of microplastic-contaminated ballast water. We conclude that there is a pressing need to include microplastics in the ballast water management convention as a hazardous material. Efficient on-board ballast water treatment strategies and effective limits for microplastics in ballast waters need to be developed.
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•Metals, chemicals and antibiotics adsorb on microplastics in contaminated waters.•V. cholerae and HAB-producing species form biofilms on microplastics.•Ballast water transports microplastics and ‘plastisphere’ communities across continents.•Disease outbreaks and Harmful Algal Blooms can occur in the recipient country.•Ballast water convention should include microplastics as a hazardous material.
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