Microplastic ingestion by small coastal fish in the northern Baltic Sea, Finland

Microplastic (MP) ingestion by four species of small coastal fish from the northern Baltic Sea was investigated. The digestive tract contents of 424 specimens, caught across eight sampling sites along the Finnish coastline were analysed for the occurrence of MP ingestion. MP were found in 38 fish individuals (9% of sampled fish). Specimens from the urban area of Helsinki displayed the highest prevalence of ingested plastics (27.5%). No relationship was found between the size or species of the fish and the presence of ingested MP particles nor the amount of MP in seawater. The comparison to a previous study conducted using the same research methods indicates that the ingestion of MP is more common in coastal fish than in offshore fish in the northern Baltic Sea.

Automated summary

The ingestion of microplastics was investigated in four species of small coastal fish from the northern Baltic Sea. 9% of sampled fish were found to have ingested microplastics, with the highest prevalence found in specimens from the urban area of Helsinki. No correlation was found between the size or species of the fish and the presence of ingested microplastic particles, nor the amount of microplastics in seawater. Comparisons to a previous study suggest that microplastic ingestion is more common in coastal fish than offshore fish in the northern Baltic Sea.