Anthropogenic microlitter in wastewater and marine samples from Ny-Ålesund, Barentsburg and Signehamna, Svalbard

Plastic pollution is recognized as a serious threat to the marine environment by the UN, the EU through the Marine Strategy Framework Directive, the Arctic council, the Nordic council, and national governments worldwide. Marine litter may reach the Arctic with ocean currents from global and regional sources, but may also originate from local emissions related to shipping and fishing activities, runoff from land based industries, dumping sites and wastewater outlets. Wastewater outlets are identified as important sources of microplastics to the marine environment in temperate areas but have received less attention in the Arctic. Wastewater treatment is generally lacking in the Arctic, and in smaller settlements, handling of wastewater (including sewage water) and garbage is comparable to conditions observed in developing countries. In Svalbard, wastewater treatment is absent aside from a small treatment plant in Hornsund and the recently installed treatment plant in Ny-Ålesund. The aim of this investigation was to quantify and characterize anthropogenic microparticles (AMPs: particles <5 mm of manmade or modified materials, e.g. plastics, paints, rubber and textile fibers) in wastewater from the recently installed treatment plant in Ny-Ålesund (Kongsfjorden), in the marine environment close to the Russian settlement Barentsburg (Grønnfjorden), and in Signehamna (Krossfjorden) far from permanent land-based human impact. Samples of seawater, marine sediments and beach sediments were collected and analyzed for AMPs using optical and spectroscopic techniques. AMPs were found at all sites and in all matrices investigated in this study. AMPs identified in wastewater and seawater were dominated by fibres (both non-synthetic and synthetic) while AMPs identified in sediment samples were dominated by fragments. Higher concentrations of AMPs and higher polymeric diversity was observed closer to human activities; in sediments close to Ny-Ålesund wastewater outlet and in seawater close to both Barentsburg and Ny-Ålesund, as compared to the remote site at Signehamna. Based on this investigation, as much as 99 % of the incoming AMPs may be retained by the wastewater treatment plant in Ny-Ålesund. It is thus clear that installation of appropriate wastewater treatment systems can substantially reduce the release of anthropogenic microlitter and potential associated contaminants to the marine environment. However, this investigation is based on a limited number of samples and a comprehensive investigation should be conducted to determine the true efficiency of the wastewater treatment plant in Ny-Ålesund, covering both temporal and spatial variation. The present report should be used as a first step towards resolving the issue of lacking wastewater treatment in Svalbard and in the Arctic as a whole.