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−1 and 0.97 (±2.61) particles w.w. g−1 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. | publishedVersion

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−1 and 0.97 (±2.61) particles w.w. g−1 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.

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⁻¹ and 0.97 (±2.61) particles w.w. g⁻¹ 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.

We tested a trait-based approach to link a soil disturbance to changes in invertebrate communities. Soils and macro-invertebrates were sampled in sandy soils contaminated by long-term wastewater irrigation, adding notably organic matter and trace metals (TM). We hypothesized that functional traits of invertebrates depict ways of exposure and that exposure routes relate to specific TM pools. Geophages and soft-body invertebrates were chosen to inform on exposure by ingestion or contact, respectively. Trait-based indices depicted more accurately effects of pollution than community density and diversity did. Exposure by ingestion had more deleterious effects than by contact. Both types of exposed invertebrates were influenced by TM, but geophages mainly responded to changes in soil organic matter contents. The trait-based approach requires to be applied in various conditions to uncorrelate specific TM impacts from those of other environmental factors.

We tested a trait-based approach to link a soil disturbance to changes in invertebrate communities. Soils and macro-invertebrates were sampled in sandy soils contaminated by long-term wastewater irrigation, adding notably organic matter and trace metals (TM). We hypothesized that functional traits of invertebrates depict ways of exposure and that exposure routes relate to specific TM pools. Geophages and soft-body invertebrates were chosen to inform on exposure by ingestion or contact, respectively. Trait-based indices depicted more accurately effects of pollution than community density and diversity did. Exposure by ingestion had more deleterious effects than by contact. Both types of exposed invertebrates were influenced by TM, but geophages mainly responded to changes in soil organic matter contents. The trait-based approach requires to be applied in various conditions to uncorrelate specific TM impacts from those of other environmental factors.

We tested a trait-based approach to link a soil disturbance to changes in invertebrate communities. Soils and macro-invertebrates were sampled in sandy soils contaminated by long-term wastewater irrigation, adding notably organic matter and trace metals (TM). We hypothesized that functional traits of invertebrates depict ways of exposure and that exposure routes relate to specific TM pools. Geophages and soft-body invertebrates were chosen to inform on exposure by ingestion or contact, respectively. Trait-based indices depicted more accurately effects of pollution than community density and diversity did. Exposure by ingestion had more deleterious effects than by contact. Both types of exposed invertebrates were influenced by TM, but geophages mainly responded to changes in soil organic matter contents. The trait-based approach requires to be applied in various conditions to uncorrelate specific TM impacts from those of other environmental factors.

Chlordecone was applied between 1972 and 1993 in banana fields of the French West Indies. This resulted in long-term pollution of soils and contamination of waters, aquatic biota, and crops. To assess pollution level and duration according to soil type, WISORCH, a leaching model based on first-order desorption kinetics, was developed and run. Its input parameters are soil organic carbon content (SOC) and SOC/water partitioning coefficient (Koc). It accounts for current chlordecone soil contents and drainage water concentrations. The model was valid for andosol, which indicates that neither physicochemical nor microbial degradation occurred. Dilution by previous deep tillages makes soil scrapping unrealistic.Lixiviation appeared the main way to reduce pollution. Besides the SOC and rainfall increases, Koc increased from nitisol to ferralsol and then andosol while lixiviation efficiency decreased. Consequently, pollution is bound to last for several decades for nitisol, centuries for ferralsol, and half a millennium for andosol.

Chlordecone was applied between 1972 and 1993 in banana fields of the French West Indies. This resulted in long-term pollution of soils and contamination of waters, aquatic biota, and crops. To assess pollution level and duration according to soil type, WISORCH, a leaching model based on first-order desorption kinetics, was developed and run. Its input parameters are soil organic carbon content (SOC) and SOC/water partitioning coefficient (Koc). It accounts for current chlordecone soil contents and drainage water concentrations. The model was valid for andosol, which indicates that neither physico-chemical nor microbial degradation occurred. Dilution by previous deep tillages makes soil scrapping unrealistic. Lixiviation appeared the main way to reduce pollution. Besides the SOC and rainfall increases, Koc increased from nitisol to ferralsol and then andosol while lixiviation efficiency decreased. Consequently, pollution is bound to last for several decades for nitisol, centuries for ferralsol, and half a millennium for andosol. Soil and water contamination by chlordecone will persist for several centuries in the French West Indies, because the only decontamination is through leaching by drainage water.

Chlordecone was applied between 1972 and 1993 in banana fields of the French West Indies. This resulted in long-term pollution of soils and contamination of waters, aquatic biota, and crops. To assess pollution level and duration according to soil type, WISORCH, a leaching model based on first-order desorption kinetics, was developed and run. Its input parameters are soil organic carbon content (SOC) and SOC/water partitioning coefficient (Koc). It accounts for current chlordecone soil contents and drainage water concentrations. The model was valid for andosol, which indicates that neither physicochemical nor microbial degradation occurred. Dilution by previous deep tillages makes soil scrapping unrealistic.Lixiviation appeared the main way to reduce pollution. Besides the SOC and rainfall increases, Koc increased from nitisol to ferralsol and then andosol while lixiviation efficiency decreased. Consequently, pollution is bound to last for several decades for nitisol, centuries for ferralsol, and half a millennium for andosol.