Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study

Abstract

Microplastic (MP) contamination is ubiquitous in the environment and many species worldwide have been shown to contain MP. The ecological impact of MP pollution is still unknown, thus there is an urgent need for more knowledge. One key task is to identify species suitable as sentinels for monitoring in key eco-compartments, such as coastal waters. In Norway, mussels (Mytilus spp.) have been monitored for hazardous contaminants through OSPAR since 1981. Norway has the longest coastline in Europe and adding MP to the Norwegian Mussel Watch is therefore important in a European and global context. The present study reports MP data in mussels (332 specimens) collected from multiple sites (n = 15) spanning the whole Norwegian coastline. MPs were detected at all locations, except at one site on the west coast. Among the most surprising findings, mussels from the Barents Sea coastline in the Finnmark region, contained significantly more MPs than mussels from most of the southern part of the country, despite the latter sites being located much closer to major urban areas. Only mussels from a site located very close to Oslo, the capital, contained levels similar to those observed in the remote site in Finnmark. In total an average of 1.5 (±2.3) particles ind and 0.97 (±2.61) particles w.w. g was found. The most common MPs were <1 mm in size, and fibres accounted for 83% of particles identified, although there was inter-site variability. Thirteen different polymeric groups were identified; cellulosic being the most common and black rubbery particles being the second. This study suggests Mytilus spp. are suitable for semi-quantitative and qualitatively monitoring of MPs in coastal waters. However, some uncertainties remain including mussel size as a confounding factor that may influence ingestion, the role of depuration and other fate related processes, and this call for further research.

How to get rid of ingested microplastic fibers? A straightforward approach of the Atlantic ditch shrimp Palaemon varians

“…So far, however, presence of fibers was reported in various species of seafood (Rochman et al, 2015). Blue mussels were examined for their suitability to monitor microplastic pollution in Norwegian coastal waters where mussels contained on average 1.5 microplastics per individual (Bråte et al, 2018). Overall, 83% of the particles investigated in that study were fibers.…”

The rapid increases in microplastics in urban lake sediments

“…MPs are considered an emerging pollutant 3 because they have strong abilities to become enriched in heavy metals 4,5 and persistent organic pollutants (POPs) 6,7 and can affect the growth of organisms 8 . Since 2013, extensive data have been accumulated on the spatial distribution of MPs in coastal areas 9,10 , oceans 11,12 , rivers 13,14 , lakes 15,16 , sediments 17,18 and soil 19,20 . MPs have been found in remote areas 21,22 , which confirmed that MPs could be transported over long distances via the atmosphere 21 and ocean currents 12,15 , which makes MPs an extensive global pollutant.…”

Solving a Sticky Situation: Microplastic Analysis of Lipid-Rich Tissue

“…Samples were not processed inside a clean air device (Wesch et al, 2017). To apply this workflow to environmental samples, it is recommended to follow established QA/QC method, such as those described in Karami et al (2017), Bråte et al (2018), or Hermsen et al (2018.…”