Review of Microplastic Pollution in the Environment and Emerging Recycling Solutions

Microplastic pollution represents a side-effect stemming from a global plastic waste mismanagement problem and includes degraded particles or mass produced plastic particles less than 5 mm in largest dimension.The small nature of microplastics gives this area of pollution different environmental concerns than general plastic waste in the environment.The biological toxicity of particles,their internal components,and their surface level changes all present opportunities for these particles to adversely affect the environment around them.Thus,it is necessary to review the current literature surrounding this topic and identify areas where the study of microplastic can be pushed forward.Here we present current methods in studying microplastics,some of the ways by which microplastics affect the environment and attempt to shed light on how this research can continue.In addition,we review current recycling methods developing for the processing of mixed-plastic waste.These methods,including hydrothermal processing and solvent extraction,provide a unique opportunity to separate plastic waste and improve the viability of the plastics recycling industry.

Are Antarctic Specially Protected Areas safe from plastic pollution? a survey of plastic litter at Byers Peninsula, Livingston Island, Antarctica

A number of studies have reported in the last decades the presence of plastics in the Southern Ocean,which are liable to reach the coast and accumulate on the Antarctic Continent.Despite this,there are few data on the amount of plastic pollution on Antarctic beaches below 60°S.Here we provide valuable information about the presence of plastic debris in Byers Peninsula,Livingston Island,South Shetland Islands,an Antarctic Specially Protected Area(ASPA)and a hotspot for biodiversity.A total of 129 locations with between 1 and 5 items were recorded among the 3 survey sites on Byers Peninsula.Most of the observed items are likely to derive from fishing and local sources such as tourism and research activities.We discuss the potential impacts of their presence on local fauna and some of the consequences on the Antarctic ecosystem.From this survey of plastic accumulation in an ASPA,we propose the implementation of mitigation strategies,such as systematic monitoring of the abundance and distribution of plastic waste,in order to identify trends in marine debris and control the levels of plastic pollution in the Maritime Antarctic region.

The Cost of Plastic Pollution in N’Djamena: A Case Study

Plastic pollution is a major problem: it damages health, reduces ecosystem services, and affects local economies. Despite its importance, available valuation efforts have focused primarily on the damages caused by plastic in marine environments. Far less is known about the effects of plastic waste in inland settings. This paper addresses this gap by estimating in monetary terms the damages caused by the inappropriate disposal of plastic waste in an inland context. The study area is located along a canal that crosses N’Djamena, the capital of Chad. Using data from a primary survey and applying standard valuation techniques, the paper estimates the social cost of plastic pollution at over USD3000 per ton in 2020. In addition, it shows that the impacts of plastic waste vary significantly across the study area: households residing within 20 meters of the canal bear more than 75 percent of the total damages. The paper identifies the main valuation challenges and proposes recommendations to reduce plastic waste damages.

Birds and plastic pollution:recent advances

Plastic waste and debris have caused substantial environmental pollution globally in the past decades,and they have been accumulated in hundreds of terrestrial and aquatic avian species.Birds are susceptible and vulnerable to external environments;therefore,they could be used to estimate the negative effects of environmental pollution.In this review,we summarize the effects of macroplastics,microplastics,and plastic-derived additives and plastic-absorbed chemicals on birds.First,macroplastics and microplastics accumulate in different tissues of various aquatic and terrestrial birds,suggesting that birds could suffer from the macroplastics and microplastics-associated contaminants in the aquatic and terrestrial environments.Second,the detrimental effects of macroplastics and microplastics,and their derived additives and absorbed chemicals on the individual survival,growth and development,reproductive output,and physiology,are summarized in different birds,as well as the known toxicological mechanisms of plastics in laboratory model mammals.Finally,we identify that human commensal birds,long-life-span birds,and model bird species could be utilized to different research objectives to evaluate plastic pollution burden and toxicological effects of chronic plastic exposure.

Primary and Secondary Microplastic and Nanoplastic Regulations: Perspectives on Water Industry Impacts

Plastic pollution, both primary and secondary, is an environmental challenge, prompting regulatory actions at global and regional levels. With increasing research about the impacts of micro- and nanoplastics on ecosystems and human health, governments worldwide have undertaken efforts to address this issue. The global community has advanced regulatory efforts that have led to the implementation of national laws or regulations in numerous countries. These measures ban or restrict the use of primary and secondary microplastics and nanoplastics. An overview of global and European regulatory frameworks is presented to provide context for the United States (US). In the endeavor to document plastics regulation development in the US, a description of regulatory agencies and their roles in advancing policy and rules as well as future direction and areas for improvement in regulating plastics are introduced. A discussion of what emerging regulations mean to utilities and industries is also provided along with a comparison of regulatory frameworks.

Recovery of plastics from dumpsites and landfills to prevent marine plastic pollution in Thailand

Marine plastic pollution has become a major threat to the ecosystem.The increasing production and use of plastic,combined with limitations of waste management practices,mean the leakage of plastic waste into the environment is bound to increase.This study focuses on the determination of plastic recovery potential from dumpsites and landfills in Thailand,to potentially prevent marine plastic pollution.In this study,two dumpsites were analysed wherein an average of 42% of plastic was found to be present.This value,when extrapolated for Thailand,is equivalent to 187.9 million tonnes of plastic waste in dumpsites and landfills.While there are 2380 dumpsites in the country,this study suggests that 973 of these spread over 42 provinces are located near water bodies or coastline,which should be considered as a priority.The plastic waste recovered from these dumpsites can be treated by co-fuelling in cement industries.Cement kilns can valorise plastic waste as they can reach up to 75%energy recovery from waste,which is much higher compared to traditional waste-to-energy plants.With adequate incentives and sound regulations,cement industries could help in the reduction of marine plastic pollution with controlled emissions and a very large capacity to co-fuel cement production,there is a readily available solution to manage the large volumes of solid waste generated.

Plastic supported platinum modified nickel electrode and its high electrocatalytic activity for sodium borohydride electrooxidation

A novel plastic/multi-walled carbon nanotube（MWNTs）-nickel（Ni）-platinum（Pt） electrode（PMNP） is prepared by chemical-reducing Pt onto the surface of Ni film covered plastic/MWNTs（PM） substrate. The MWNTs are adhered by a piece of commercial double faced adhesive tape on the surface of plastic paper and the Ni film is prepared by a simple electrodeposition method. The morphology and phase structure of the PMNP electrode are characterized by scanning electron microscopy,transmission electron microscope and X-ray diffractometer. The catalytic activity of the PMNP electrode for Na BH4 electrooxidation is investigated by means of cyclic voltammetry and chronoamperometry. The catalyst combines tightly with the plastic paper and exhibits a good stability. MWNTs serve as both conductive material and hydrogen storage material and the Ni film and Pt are employed as electrochemical catalysts. The PMNP electrode exhibits a high electrocatalytic performance and the oxidation current density reaches to 10.76 A/（mg·cm） in 0.1 mol/dm3 Na BH4at0 V,which is much higher than those in the previous reports. The using of waste plastic reduces the discarding of white pollution and consumption of metal resources.

Sustainable plasticulture in Chinese agriculture: a review of challenges and routes to achieving long-term food and ecosecurity

Plastic pollution is global concern, affecting most aspects of global food production systems. Plasticulture, a practice used in agriculture to improve crop quality and quantity, among other factors, is a significant source of plastic pollution. This review examines the extent of plasticulture in China, the implications of the practice across decades of use and the legislative instruments used to resolve those issues. It briefly assesses the effectiveness of these policies and proposes possible future innovations to promote increases in long-term food and eco-security, where sustainable plasticulture is a key agent for change. While plasticulture has increased agricultural productivity in growth-limiting conditions, plastic pollution in agricultural soils has become acute in China. Consequently, plastic pollution is having deleterious effects on soil health and in turn, crop productivity in China. Plastic pollution in agriculture is a multifaceted issue and so proposed solutions should be informed by this complexity. Current measures do not reflect a holistic approach to solving this socioecological challenge and adopt a top-down approach, with little or no supportive mechanisms. Future recommendations need to consider the particular set of conditions that influence the production, use and end-of-life management of agriplastics,specific to the environmental, economic and social conditions in each location.

Analysis of the Solid Contents of Toothpastes Available in UAE (United Arab Emirates) Markets

In order to find out whether any toothpastes commercially available in the United Arab Emirates (UAE) carry microplastic content in form of plastic microbeads, the filterable solid contents of 31 toothpastes from UAE markets and 2 toothpastes imported from Syria were analyzed. FT-IR studies of the solids revealed that the major solid components were hydrated silica and calcium carbonate, where the individual toothpaste product exhibited either one or the other as the dominant constituent. Titrimetric analysis of the alkalinity of the ash of the toothpastes was carried out. The solids, ashed at 600°C were subjected to FT-IR and EDS (energy dispersive X-ray spectroscopic) analysis. The ash of some of the products was shown to have TiO2 and Ca3 (PO4)2 as minor components. Mostly organic dyes were used as colorants;however, iron oxide (Fe2O3) was also found. Importantly, none of the toothpastes carried any solid microplastic particles. Only 3 toothpastes carried microbeads at all, which were made of either silica or microcrystalline cellulose. This finding indicates that toothpastes, at least in the UAE, are no longer a significant source of microplastic in the environment. The results were compared to a toothpaste bought through the internet with a formulation from 2014, which exhibited polythene microplastic at 1.31 ± 0.39 w% of the filterable solid content.

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

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.Fromthe online databases,we developed a compilation of emergingresearch 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 m microplastic abundance,size,shape,color,and polymer type found were depended on the sampling sites and relevant anthropogenic activities.It is imperative to identify majorsources 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.

Resource utilization of typical biomass wastes as biochars in removing plasticizer diethyl phthalate from water: characterization and adsorption mechanisms

Plastic pollution as a global environmental issue has become a research hotspot,among which the removal of inherent plasticizer(e.g.,phthalic acid esters,PAEs)received increasing attention.However,the effects of biochars derived from different feedstocks on the adsorption of PAEs are poorly understood.Thus,the characteristics of biochars derived from six largely produced biomass wastes in China at 400°C,as well as their performance in adsorption of diethyl phthalate(DEP),one of frequently detected PAEs in aqueous environment,were investigated.The results indicated that the variation in feedstock type showed significant changes in the properties(e.g.,porosity,specific surface area,surface functional groups)of biochars,which affected DEP adsorption and desorption.Pseudosecond order and Freundlich models fitted the adsorption data well,and adsorption mechanisms mainly included hydrophobic effect,followed by micropore filling,hydrogen bonding,andπ-πEDA interactions.Adsorption thermodynamics revealed that the adsorption was a spontaneous and exothermic the adsorption capacities of DEP on these biochars slightly decreased with the increasing pH but increased with the increasing ionic strength.Among these biochars,the giant reed biochar with relatively higher DEP adsorption and low desorption exhibited the great efficiency for DEP removal as an environment-friendly sorbent.These results highlighted the significant roles of micropore filling and hydrogen bond in determining adsorption capacity of designed biochars prepared from selecting suitable agricultural straws and wetland plant waste to typical plasticizer.The findings are useful for producing designed biochars from different biomass wastes for plasticizer pollution control.

Distribution of microplastics in mulched soil in Xinjiang, China

In order to study the distribution of soil microplastics in the plastic film mulched farmland,the fluidization-centrifugation secondary density flotation method was optimized and improved to obtain the samples.The main components of microplastics were analyzed by Fourier spectrometer,and the surface morphology,porosity,particle size and abundance distribution characteristics of microplastics were studied by electron microscopy.The results showed that plastic mulch is the main source of microplastics.Its morphology mainly consists of fragments,fibers and particles.The size of debris microplastics was larger,with an average of 1.6300 mm,mainly distributed in the 0-300 mm cultivation layer while the size of particle micro plastic was smaller,with an average of 0.1400 mm.The width of fiber microplastic was 5-20μm,but the length could reach 0.2000-2.0000 mm,with an average particle size of 0.9200 mm.Fiber and granular microplastics could be seen in each soil layer.The surface layer of microplastics has a large number of pores characterized with a length of 50μm and a width of about 5-10μm,which might be an easy oxidation site for microplastics.This oxidation is continuous,making microplastics continuously decompose into smaller particles.The abundance of microplastics is negatively correlated with soil depth.The average abundance of microplastics is 161.50±5.20 pieces/100 g in 0-300 mm soil layer,which is their main enrichment area.However,the average abundance of microplastics decreases to 11.20±1.10 pieces/100 g in 400-800 mm soil depth.Moreover,the average particle size of microplastics is also linearly negatively correlated with soil depth.Microplastics with smaller particle size are easier to migrate as they pass through soil pores under the action of water and fertilizer.The research can provide s reference for understanding plastic mulch pollution.

Plastic ingestion and associated additives in Faroe Islands chicks of the Northern Fulmar Fulmarus glacialis

Northern Fulmars(Fulmarus glacialis)are a pelagic seabird species distributed at northern and polar latitudes.They are often used as an indicator of plastic pollution in the North Sea region,but data are lacking from higher latitudes,especially when it comes to chicks.Here,we investigated amounts of ingested plastic and their characteristics in fulmar chicks from the Faroe Islands.Plastic particles(≥1 mm)in chicks of two age classes were searched using a digestion method with KOH.In addition,to evaluate if additive tissue burden reflects plastic ingestion,we measured liver tissue concentrations of two pollutant classes associated with plastic materials:polybrominated diphenyl ethers(PBDEs)and several dechloranes,using gas chromatography with high-resolution mass spectrometry.The most common shape was hard fragment(81%)and the most common polymer was polyethylene(73%).Plastic contamination did not differ between either age class,and we found no correlation between neither the amount and mass of plastic particles and the concentration of additives.After comparison with previous studies on adult fulmars,we do not recommend using chicks for biomonitoring adults because chicks seem to ingest more plastics than adults.

Impact of agricultural residual plastic film on the growth and yield of drip-irrigated cotton in arid region of Xinjiang, China

Long-term and widespread use of plastic mulching has led to the accumulation of residual plastic film(RPF)in farmland soils of Xinjiang,China.However,there is no specific quantitative basis for RPF pollution or a clear understanding of the influence of residual film on crop growth.The aim of this study was to investigate the effect of RPF on the growth of cotton,an important cash crop of Xinjiang.Based on the field conditions and previous reports,various amount of residual film was applied in 0-30 cm soil layer.The growth index including emergence rate,dry matter,and yield of cotton was examined at different growth stages under different soil residual film levels.Results demonstrated a significant effect of RPF on soil moisture distribution and movement.Plastic residues had a significant effect on cotton growth at levels above 200 kg/hm2,and the yield decreased as the RPF amount increased.Based on these findings,200 kg/hm2 was suggested as a threshold level to determine the effects of RPF on cotton.This study provided a basis to rate RPF pollution in farmland soils and help understand the impact of pollution on crop productivity.