We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Endangered, exploited glass eels (Anguilla anguilla) with critical levels of heavy metals and microplastics reveal both shipping and plastic spill threats
Summary
Researchers measured heavy metals and microplastics in endangered European glass eels and the estuarine waters they pass through in the Bay of Biscay region. They found that cadmium levels in eels from all estuaries exceeded legal European limits, and some waterways showed microplastic concentrations above ecotoxicological thresholds. The findings highlight the compounding threats that chemical and microplastic pollution pose to this already critically endangered species.
In the life of the endangered but still fished Anguilla anguilla, glass eels are recruited through estuaries. These fragile ecosystems are among the most disturbed on the planet. Here, heavy metals and microplastics were measured in estuary water and European glass eels entering bay of Biscay rivers of different size and anthropogenic stress. Eels from all the estuaries exhibited cadmium exceeding legal European limits, as happened with lead in samples from the highly disturbed Avilés estuary. Several water samples from small rivers surpassed the estimated limit of microplastic for ecotoxicological safety. In multiple regression analysis, both eel lead and microplastic content were significantly explained from shipping activity in the estuaries. Eel cadmium content was not associated with estuary stressors, being probably acquired during the oceanic migration of eel larvae. The presence in eels of new white polyethylene particles that had not been found previously in the region could be explained from the marine plastic spill of "Toconao" cargo in December. The same spill could explain a significant increase of microplastic bioconcentration in the glass eels in comparison with previous surveys. These risks for critically endangered eels, and for the consumers, highlight the urgent need for reducing the impact of contaminants on both local and global scales.
Sign in to start a discussion.
More Papers Like This
Microplastics across biomes in diadromous species. Insights from the critically endangered Anguilla anguilla
Researchers examined microplastic ingestion in young European eels across freshwater and marine environments, finding these critically endangered diadromous fish are exposed to microplastic contamination in both habitats throughout their life cycle.
Low microplastic loads in riverine European eel (Anguilla anguilla) from southwest England during their marine–freshwater transition
This study found very low levels of microplastic contamination in juvenile European eels (elvers) from three rivers in southwest England, with only 3.3% of individuals carrying particles. While contamination levels were low, the results establish a baseline for monitoring trends in this critically endangered migratory fish species.
Molecular responses to pollution stress in glass eels (Anguilla anguilla): Gene expression changes associated with varying contamination levels and temperature across estuaries
Researchers measured gene expression in European eel glass eels entering estuaries with varying levels of microplastic and heavy metal contamination, finding that pollution and temperature shifts alter stress-response and metabolic gene expression in ways that may impair survival.
Microplastics increase mercury bioconcentration in gills and bioaccumulation in the liver, and cause oxidative stress and damage in Dicentrarchus labrax juveniles
Researchers exposed juvenile European sea bass to mercury, microplastics, and their mixture for 96 hours and found that microplastics increased mercury bioconcentration in gills and bioaccumulation in the liver. The combination of microplastics and mercury also caused greater oxidative stress and lipid damage than either contaminant alone, suggesting microplastics may amplify the toxicity of co-occurring pollutants.
Bisphenol A and its analogs in muscle and liver of fish from the North East Atlantic Ocean in relation to microplastic contamination. Exposure and risk to human consumers
Researchers measured levels of bisphenol A and related compounds in the muscle and liver of three fish species from the North East Atlantic Ocean and assessed the relationship with microplastic contamination. Fish containing microplastics had significantly higher concentrations of bisphenols than those without, suggesting microplastics may be a vehicle for chemical contamination. The estimated health risk from consuming these fish exceeded safety thresholds set by the European Food Safety Authority.