Are rare earth elements emerging contaminants of concern in the marine environment in Norway? (ELEMENTARY)

Informations

Funding country

Norway

Acronym

-

URL

-

Start date

1/1/2020

End date

12/31/2023

Budget

1,459,395 EUR

Fundings

Abstract

The 15 lanthanoid together with yttrium form the group of rare earth elements and yttrium (REY). They are essential elements for the green shift and rated as technology critical elements as they are used in many products and applications reaching from batteries, magnets, light source components, fuel additives, fertilizers and medical contrast agents. The rapidly rising demand, production and use will lead to their release into the environment. However, knowledge on REY concentrations in Norwegian marine environments and their potential effects on marine species is lacking. In ELEMENTARY we measure concentrations of REY in different species collected at potential release hot-spots in coastal environments in Norway. Normalised REY patterns in water samples and biota will help us understand if a) REY are released from anthropogenic activities in detectable quantities, and b) if REY are taken up into organisms and which organism groups are most likely to accumulate REEs. Further, we study effects of selected REY and anthropogenic REY (Gd used as MRI contrast agent) on different fish species in laboratory experiments. REYs were determined in marine organisms (different macroalgae, bivalves, crabs) from 3 different locations: (1) Lindesnes - located near an industry producing Gd-based MRI contrast agents (GBCA), (2) Frier fjord, Porsgrunn – in vicinity of Herøya Industrial Park (phosphate fertilizers production) and (3) Trondheimsfjord – potentially affected by wastewater treatment plants (WWTPs). Results from Lindesnes show that blue mussels (M. edulis) downstream of the industry outfall have a fourfold positive Gd anomaly. Normalization with European shale indicated a clear excess uptake of anthropogenic Gd by mussels in this area. A correlation analysis revealed a significant positive association between the soft tissue weight of each individual mussel and the SREY concentrations, indicating bioaccumulation of these elements in blue mussels over their lifespan. Surprisingly, high total REY concentrations were found in clams (Tapes spp.) from the vicinity of Herøya Industrial Park (Porsgrunn), which seem to be the highest SREY concentrations ever recorded in bivalves. Whether these high REY concentrations in clams are related to local pollution sources, the clams physiology, the riverine character or geochemical features of the area, is to be determined. Edible crabs, C. pagurus generally had the highest REYs burden in gills and much less in hepatopancreas and muscle. This pattern indicates that the main mechanism of uptake in crabs is active uptake through the water and sediment particles rather than through the diet. Using the results from the gills, we assessed the spatial distribution of REY concentrations in Frier fjord. Crabs in the sites closer to the Knardalstrand wastewater treatment plant discharge point and the Skien river outlet had three to four times higher total REY concentrations than those in the reference site 8 km away. We further measured REY in the macroalgae species Fucus vesiculosus, Saccharina latissima and Ascophyllum nodosum. In samples taken in Trondheimsfjord we found higher REY concentrations at the sampling site in Lade close to one of the wastewater treatment plants. However, we did not find the same pattern the Ascophyllum nodosum. Similarly, in Lindesnes, Fucus sp. had significantly higher concentrations of REYs in the vicinity of the wastewater discharge compared to the reference site. We did not find similar patterns in the other analyzed species. The results of our field study show that REY accumulation varies between species of different trophic levels, between species of similar organizational level and between organs of the same organism, and thus provides important information for future biomonitoring studies. Our studies on potential toxic impacts showed that inorganic unchelated Gd (GdCl3) was toxic to fish larvae, while the complexed Gd in form of the contrast agent (GBCA) had no effects at the tested concentrations. Observed effects included reduced viability, craniofacial deformities, lordosis, reduced pigmentation, and behavioural changes. Similarly, exposure to GdCl3 caused effects on neuronal activity in zebrafish larvae brains. Effects on molecular level are currently studied. Further, we currently investigate bioavailability and effects of different forms of Gd in lumpfish. Juvenile lumpfish were exposed to GdCl3 and a GBCA, with organ distribution and potential effects on both cellular and molecular level currently being analysed.