Occurrence and spatial distribution of microplastics in sediments from Norderney.

The spatial distribution of small potential microplastics (SPM) (<1 mm) in beach sediments was studied on a 500 m stretch of the North Sea island of Norderney. Their correlation with visible plastic debris (VPD) (>1 mm) was also examined. Small microparticles were extracted from 36 one kg sediment samples and analysed by visual microscopic inspection and partly by thermal desorption pyrolysis gas chromatography/mass spectrometry. The smallest particle size that could be analysed with this method was estimated to be 100 μm. The mean number of SPM at the three sampling sites (n = 12) was 1.7, 1.3 and 2.3 particles per kg dry sediment, respectively. SPM were identified as polypropylene, polyethylene, polyethylene terephthalate, polyvinylchloride, polystyrene and polyamide. The organic plastic additives found were benzophenone, 1,2-benzenedicarboxylic acid, dimethyl phthalate, diethylhexyl phthalate, dibutyl phthalate, diethyl phthalate, phenol and 2,4-di-tert-butylphenol. Particles were distributed rather homogenously and the occurrence of SPM did not correlate with that of VPD.

Dekiff JH ，Remy D ，Klasmeier J ，Fries E ... -  《-》

A new analytical approach for monitoring microplastics in marine sediments.

A two-step method was developed to extract microplastics from sediments. First, 1 kg sediments was pre-extracted using the air-induced overflow (AIO) method, based on fluidisation in a sodium chloride (NaCl) solution. The original sediment mass was reduced by up to 80%. As a consequence, it was possible to reduce the volume of sodium iodide (NaI) solution used for the subsequent flotation step. Recoveries of the whole procedure for polyethylene, polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polystyrene and polyurethane with sizes of approximately 1 mm were between 91 and 99%. After being stored for one week in a 35% H2O2 solution, 92% of selected biogenic material had dissolved completely or had lost its colour, whereas the tested polymers were resistant. Microplastics were extracted from three sediment samples collected from the North Sea island Norderney. Using pyrolysis gas chromatography/mass spectrometry, these microplastics were identified as PP, PVC and PET.

Nuelle MT ，Dekiff JH ，Remy D ，Fries E ... -  《-》

First record of characterization, concentration and distribution of microplastics in coastal sediments of an urban fjord in south west Norway using a thermal degradation method.

Plastic waste is of increasing concern in the aquatic environment. A large proportion of plastic waste is generated onshore from where it eventually reaches the marine environment, which is considered the main sink of plastic debris To date there is a substantial lack of knowledge on the composition of these accumulated polymers, their environmental levels and distribution in marine and coastal areas. Current efforts are underway to develop standardized methods to characterize and quantify the occurrence of microplastic in different environmental matrices using microscopy-oriented methods using Fourier Transformed Infra-Red (FTIR) or Raman techniques. However, time-consuming sample preparation, processing and interpretation of complex data limits their use within monitoring programs. As an alternative, a thermal degradation method based on a gas chromatographic mass spectrometer coupled with pyrolysis represents a validated method for qualitative and quantitative polymer analyses. A technique has been developed that combines sample preparation and thermo-analysis for identifying microplastics in samples of marine sediment. Quantification and polymeric composition of plastic particles found in sediment samples taken from ten sites located in Boknafjorden subjected to diverse sources of pollution and anthropogenic pressure were investigated. Plastic microparticles were extracted from 8 kg of wet sediments per site, purified, size-fractionated thorough a set of stainless-steel certified sieves covering the range of 10-250 μm mesh size, pre-concentrated on fiberglass filters and whole filters analyzed by thermal desorption pyrolysis gas chromatography/mass spectrometry. Most of the detected polymers were identified as polypropylene, polyethylene, polyethylene terephthalate, polyvinylchloride, polystyrene or polyamide. In most of the sites, the largest fraction of the extracted micro debris fell in the size range 10-40 μm. Some shifts in size distribution were also observed in some sites and were likely related to the marine sea bottom currents and the influence of specific anthropogenic activities. The adopted thermal degradation method showed good sensitivity, reliability and rapidity and therefore represents a promising technique for microplastic analysis within monitoring activities.

Gomiero A ，Øysæd KB ，Agustsson T ，van Hoytema N ，van Thiel T ，Grati F ... -  《-》

Identification of polymer types and additives in marine microplastic particles using pyrolysis-GC/MS and scanning electron microscopy.

Fries E ，Dekiff JH ，Willmeyer J ，Nuelle MT ，Ebert M ，Remy D ... -  《-》

Microplastic pollution in deep-sea sediments.

Microplastics are small plastic particles (<1 mm) originating from the degradation of larger plastic debris. These microplastics have been accumulating in the marine environment for decades and have been detected throughout the water column and in sublittoral and beach sediments worldwide. However, up to now, it has never been established whether microplastic presence in sediments is limited to accumulation hot spots such as the continental shelf, or whether they are also present in deep-sea sediments. Here we show, for the first time ever, that microplastics have indeed reached the most remote of marine environments: the deep sea. We found plastic particles sized in the micrometre range in deep-sea sediments collected at four locations representing different deep-sea habitats ranging in depth from 1100 to 5000 m. Our results demonstrate that microplastic pollution has spread throughout the world's seas and oceans, into the remote and largely unknown deep sea.

Van Cauwenberghe L ，Vanreusel A ，Mees J ，Janssen CR ... -  《-》