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Wei Chen, Zhen-Yu Ouyang, Chen Qian, Han-Qing Yu
The occurrence of microplastics (MPs) as emerging contaminants in the environment may cause changes in water or sediment characteristics, and further affect their biogeochemical cycles. Thus, insights into the interactions between dissolved organic matter (DOM) and MPs are essential for the assessment of environmental impacts of MPs in ecosystems. Integrating spectroscopic methods with chemometric analyses, this work explored the chemical and microstructural changes of DOM-MP complex to reveal the mechanism of DOM-MP interaction at a molecular level...
October 16, 2017: Environmental Pollution
Gerrit Renner, Torsten C Schmidt, Jürgen Schram
One key step studying interactions of microplastics with our ecological system is to identify plastics within environmental samples. Ageing processes and surface contamination especially with biofilms impede this characterisation. A complex and time consuming cleaning procedure is a common solution for this problem. However, it implies an artificial change of sample composition with a risk of losing important information or even damaging microplastic particles. In the present work, we introduce a new chemometric approach to identify heavily weathered and contaminated microplastics without any cleaning...
October 19, 2017: Analytical Chemistry
Jeremy L Conkle, Christian D Báez Del Valle, Jeffrey W Turner
Plastic debris, specifically microplastic in the aquatic environment, is an escalating environmental crisis. Efforts at national scales to reduce or ban microplastics in personal care products are starting to pay off, but this will not affect those materials already in the environment or those that result from unregulated products and materials. To better inform future microplastic research and mitigation efforts this study (1) evaluates methods currently used to quantify microplastics in the environment and (2) characterizes the concentration and size distribution of microplastics in a variety of products...
October 17, 2017: Environmental Management
Sarah Bruck, Alex T Ford
The ingestion of microplastics (plastic particles <5 mm) has been observed in a range of marine organisms, and adverse effects have been reported in several species after high concentration exposure. However, the long-term effects of low-dose ingestion remains unclear. The aim of this study was thus to assess the chronic effects of low concentrations of polystyrene microparticles to the intertidal amphipod Echinogammarus marinus, using food consumption, growth, and moulting as endpoints. Amphipods were fed a gelatinous algal feed spiked with microbeads (8 μm) in concentrations of ∼0...
October 13, 2017: Environmental Pollution
Sutapa Ghosal, Michael Chen, Jeff Wagner, Zhong-Min Wang, Stephen Wall
Pacific Ocean trawl samples, stomach contents of laboratory-raised fish as well as fish from the subtropical gyres were analyzed by Raman micro-spectroscopy (RMS) to identify polymer residues and any detectable persistent organic pollutants (POP). The goal was to access specific molecular information at the individual particle level in order to identify polymer debris in the natural environment. The identification process was aided by a laboratory generated automated fluorescence removal algorithm. Pacific Ocean trawl samples of plastic debris associated with fish collection sites were analyzed to determine the types of polymers commonly present...
October 13, 2017: Environmental Pollution
Matt McWilliams, Max Liboiron, Yolanda Wiersma
Most anthropogenic marine debris shoreline studies are conducted on sandy shores, rather than rocky coastlines. We amended a standardized protocol for monitoring marine debris on a high-loading beach composed of small rocks and cobbles in Newfoundland, Canada. Our protocol had two parts: we conducted stratified sampling to a depth of ~20cm below the surface of the rocks (standing survey), and surveyed accumulation of items on the surface of rocks every other day (loading survey). We found the vast majority of smaller items were below the surface...
October 12, 2017: Marine Pollution Bulletin
M C Vedolin, C Y S Teophilo, A Turra, R C L Figueira
Heavy metals and microplastics have been considered as threats to the marine environment and the interactions between these two pollutants are poorly understood. This study investigates the interactions between metals adsorbed in pellets collected randomly from 19 beaches along the coast of São Paulo State in southeastern Brazil, comparing these levels with those in virgin pellets. The samples were analyzed for Al, Cr, Cu, Fe, Mn, Sn, Ti and Zn by inductively coupled plasma optical emission spectroscopy (ICP-OES)...
October 12, 2017: Marine Pollution Bulletin
Camilla Krogh Frydkjær, Niels Iversen, Peter Roslev
The presence of microplastics in aquatic ecosystems is of increasing global concern. This study investigated ingestion, egestion and acute effects of polyethylene microplastics in Daphnia magna. Fate of regular shaped microplastic beads (10-106 µm) were compared with irregular shaped microplastic fragments (10-75 µm). Daphnia magna ingested regular and irregular microplastic with uptake between 0.7 and 50 plastic particles/animal/day when exposed to microplastic concentrations of 0.0001-10 g/L. Egestion of irregular fragments was slower than that of microplastic beads...
October 13, 2017: Bulletin of Environmental Contamination and Toxicology
Stephan Kubowicz, Andy M Booth
Plastics are one of the most widely used materials and, in most cases, they are designed to have long life times. Thus, plastics contain a complex blend of stabilizers that prevent them from degrading too quickly. Unfortunately, many of the most advantageous properties of plastics such as their chemical, physical and biological inertness and durability present challenges when plastic is released into the environment. Common plastics such as polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) are extremely persistent in the environment, where they undergo very slow fragmentation (projected to take centuries) into small particles through photo-, physical, and biological degradation processes(1)...
October 12, 2017: Environmental Science & Technology
Dokyung Kim, Yooeun Chae, Youn-Joo An
In recent years, discarded plastic has become an increasingly prevalent pollutant in aquatic ecosystems. These plastic wastes decompose into microplastics, which not only pose a direct threat to aquatic organisms but also an indirect threat via adsorption of other aquatic pollutants. In this study, we investigated the toxicities of variable and fixed combinations of two types of microplastics [one coated with a carboxyl group (PS-COOH) and the other lacking this functional group (PS)] with the heavy metal nickel (Ni) on Daphnia magna and calculated mixture toxicity using a toxic unit model...
October 11, 2017: Environmental Science & Technology
Rachel R Hurley, Jamie C Woodward, James J Rothwell
Microplastic contamination of the aquatic environment is a global issue. Microplastics can be ingested by organisms leading to negative physiological impacts. The ingestion of microplastics by freshwater invertebrates has not been reported outside the laboratory. Here we demonstrate the ingestion of microplastic particles by Tubifex tubifex in a major urban waterbody fed by the River Irwell, Manchester, UK. The host sediments had microplastic concentrations ranging from 56 to 2544 particles kg-1. 87% of the Tubifex ingested microplastic particles were microfibres (55 - 4100 µm in length), whilst the remaining 13% were fragments (50 - 4500 µm in length)...
October 11, 2017: Environmental Science & Technology
Christian Schmidt, Tobias Krauth, Stephan Wagner
A substantial fraction of marine plastic debris originates from land-based sources and rivers potentially act as a major transport pathway for all sizes of plastic debris. We analyzed a global compilation of data on plastic debris in the water column across a wide range of river sizes. Plastic debris loads, both microplastic (particles <5 mm) and macroplastic (particles >5 mm) are positively related to the mismanaged plastic waste (MMPW) generated in the river catchments. This relationship is nonlinear where large rivers with  population-rich catchments delivering a disproportionately higher fraction of MMPW into the sea...
October 11, 2017: Environmental Science & Technology
Anita Jemec Kokalj, Petra Horvat, Tina Skalar, Andrej Kržan
Current data regarding the effects of microplastic (MP) on terrestrial organisms are very scarce. Isopods play an important role in plant litter decomposition processes and are commonly used test species in terrestrial ecotoxicity studies. Their altered feeding behaviour and energy reserves are established biomarkers of adverse effects upon stressor exposure. For this study we assessed the effects of MP derived from plastic bag film (mean size 183±93μm) and particles from a facial cleanser (mean size 137±51μm) on the terrestrial isopod, Porcellio scaber...
October 6, 2017: Science of the Total Environment
Amy L Lusher, Gema Hernandez-Milian, Simon Berrow, Emer Rogan, Ian O'Connor
Interactions between marine mammals and plastic debris have been the focus of studies for many years. Examples of interactions include entanglement in discarded fishing items or the presence of ingested debris in digestive tracts. Plastics, including microplastics, are a form of marine debris globally distributed in coastal areas, oceanic waters and deep seas. Cetaceans which strand along the coast present a unique opportunity to study interactions between animals with macro- and microplastics. A combination of novel techniques and a review of historical data was used to complete an extensive study of cetaceans interacting with marine debris within Irish waters...
October 5, 2017: Environmental Pollution
Xiaojun Zhang, Minggang Zheng, Ling Wang, Yinghua Lou, Lei Shi, Shujun Jiang
Microplastics and synthetic musks (SMs) are two typical organic pollutants in the marine environment. In this study, the sorption of three SMs to microplastics in a simulated seawater environment was examined. Tonalide (AHTN), musk xylene (MX), and musk ketone (MK) were the musks investigated, while polypropylene (PP) was used as the microplastic. It was found that the equilibrium sorption time was about 10h and the adsorption kinetics model conformed to a Lagergren adsorption model. The adsorption capacity increased with decreasing particle size...
October 2, 2017: Marine Pollution Bulletin
Marcus Eriksen, Max Liboiron, Tim Kiessling, Louis Charron, Abigail Alling, Laurent Lebreton, Heather Richards, Barent Roth, Nicolas C Ory, Valeria Hidalgo-Ruz, Erika Meerhoff, Carolynn Box, Anna Cummins, Martin Thiel
Many typical neuston trawls can only be used during relatively calm sea states and slow tow speeds. During two expeditions to the Bay of Bengal and the eastern South Pacific we investigated whether the new, high-speed AVANI trawl (All-purpose Velocity Accelerated Net Instrument) collects similar amounts and types of microplastics as two established scientific trawl designs, the manta trawl and the DiSalvo neuston net. Using a 335 μm net, the AVANI trawl can collect microplastics from the sea surface at speeds up to 8 knots as it "skis" across the surface, whereas the manta and DiSalvo neuston trawls must be towed slowly in a less turbulent sea state and often represent shorter tow lengths...
September 28, 2017: Environmental Pollution
Sven Seidensticker, Christiane Zarfl, Olaf A Cirpka, Greta Fellenberg, Peter Grathwohl
In aqueous environments, hydrophobic organic contaminants are often associated with particles. Besides natural particles, microplastics have raised public concern. The release of pollutants from such particles depends on mass transfer, either in an aqueous boundary layer or by intraparticle diffusion. Which of these mechanisms controls the mass-transfer kinetics depends on partition coefficients, particle size, boundary conditions, and time. We have developed a semianalytical model accounting for both processes and performed batch experiments on the desorption kinetics of typical wastewater pollutants (phenanthrene, tonalide, and benzophenone) at different dissolved-organic-matter concentrations, which change the overall partitioning between microplastics and water...
October 18, 2017: Environmental Science & Technology
H S Auta, C U Emenike, S H Fauziah
The continuous accumulation of microplastics in the environment poses ecological threats and has been an increasing problem worldwide. In this study, eight bacterial strains were isolated from mangrove sediment in Peninsular Malaysia to mitigate the environmental impact of microplastics and develop a clean-up option. The bacterial isolates were screened for their potential to degrade UV-treated microplastics from polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), and polystyrene (PS). Only two isolates, namely, Bacillus cereus and Bacillus gottheilii, grew on a synthetic medium containing different microplastic polymers as the sole carbon source...
September 28, 2017: Environmental Pollution
Razegheh Akhbarizadeh, Farid Moore, Behnam Keshavarzi
Although weekly consumption of fish is recommended, the presence of contaminants in seafood has raised many concerns regarding the benefits of fish intake. In the present study microplastics (MPs) and metals' concentration in muscles of both benthic and pelagic fish species from northeast of Persian Gulf were investigated and the risk/benefit of their consumption was assessed. The results demonstrated that MPs and Hg in all species and Se in benthic species increase with size, while relationship between other metals, and fish size is not consistent...
September 21, 2017: Environmental Pollution
Anna M Elert, Roland Becker, Erik Duemichen, Paul Eisentraut, Jana Falkenhagen, Heinz Sturm, Ulrike Braun
In recent years, an increasing trend towards investigating and monitoring the contamination of the environment by microplastics (MP) (plastic pieces < 5 mm) has been observed worldwide. Nonetheless, a reliable methodology that would facilitate and automate the monitoring of MP is still lacking. With the goal of selecting practical and standardized methods, and considering the challenges in microplastics detection, we present here a critical evaluation of two vibrational spectroscopies, Raman and Fourier transform infrared (FTIR) spectroscopy, and two extraction methods: thermal extraction desorption gas chromatography mass spectrometry (TED-GC-MS) and liquid extraction with subsequent size exclusion chromatography (SEC) using a soil with known contents of PE, PP, PS and PET as reference material...
September 20, 2017: Environmental Pollution
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