Large microplastic particles in sediments of tributaries of the River Thames, UK – Abundance, sources and methods for effective quantification

Abstract

Lahive, Elma. 2017. Large microplastic particles in sediments of tributaries of the River Thames, UK -abundance, sources and methods for effective quantification.Contact CEH NORA team at noraceh@ceh.ac.ukThe NERC and CEH trademarks and logos ('the Trademarks') are registered trademarks of NERC in the UK and other countries, and may not be used without the prior written consent of the Trademark owner.  Many fragments derived from road marking paints -a previously undescribed source. Efficient methods developed for separating large microplastic particles from sediment. Inputs and behaviour of microplastics are varied and complex to predict . 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 2 AbstractSewage effluent input and population were chosen as predictors of microplastic presence in sediments at four sites in the River Thames basin (UK). Large microplastic particles (1 mm -4 mm)were extracted using a stepwise approach to include visual extraction, flotation and identification using Raman spectroscopy. Microplastics were found at all four sites. One site had significantly higher numbers of microplastics than other sites, average 66 particles 100 g -1 , 91% of which were fragments. This site was downstream of a storm drain outfall receiving urban runoff; many of the fragments at this site were determined to be derived of thermoplastic road-surface marking paints.At the remaining three sites, fibres were the dominant particle type. The most common polymers identified included polypropylene, polyester and polyarylsulphone. This study describes two major new findings: presence of microplastic particles in a UK freshwater system and identification of road marking paints as a source of microplastics. CapsuleThis study is the first to quantify microplastics of any size in river sediments in the UK and links their presence to terrestrial sources including sewage and road marking paints.

Microplastic Distribution at Different Sediment Depths in an Urban Estuary

“…In addition, the site is much closer to sewage and stormwater outfall drains, which we found to be sources of plastic pollution in previous work (Willis et al, 2017). This result is similar to those found in other studies, which found higher numbers of plastics at sites closer to storm drain outfalls (Duckett and Repaci, 2015;Horton et al, 2017). Most microplastics observed were fibers (87%).…”

Microplastics in freshwater and terrestrial environments: Evaluating the current understanding to identify the knowledge gaps and future research priorities

“…However, although 376 particle numbers are regularly found to be high near urban areas, this is not the only factor influencing 377 presence of microplastic particles. For example, Horton et al (2016), in addition to finding high 378 numbers of particles downstream of urban discharge points, also found particles in rural areas where 379 few human-associated inputs would be expected. 380…”

Weekly water quality monitoring data for the River Thames (UK) and its major tributaries (2009–2013): The Thames Initiative research platform

“…Phosphorus and nitrogen sources and dynamics in the River Thames (Neal et al, 2010a;Neal et al, 2000c) and its tributaries 15 (Bowes et al, 2012c;Jarvie et al, 2006;Jarvie et al, 2002b;Neal et al, 2000a;Neal et al, 2004;Neal et al, 2006), and how nutrients interact with river ecology (House et al, 2001;Jarvie et al, 2002a;Williams et al, 2000) have been intensively studied in recent decades. These studies were based on one to two year periods of weekly monitoring by the Centre for Ecology & Hydrology (CEH), based at a small number of individual study sites, carried out between 1997 and 2008.…”

“…The resulting data sets 10 have been extensively used as a modelling resource (Bussi et al, 2017;Bussi et al, 2016;Hutchins et al, 2016;Whitehead et al, 2015). Other studies have used the Thames Initiative monitoring sites as a framework for investigations of organic pollutants (Nakada et al, 2017;Singer et al, 2014), heavy metals (Turner et al, 2014), emerging contaminants (Horton et al, 2017), and antimicrobial resistance (Amos et al, 2015).…”