The global issue of ocean pollution with plastics has raised significant concerns in recent years. Beyond its impact on marine life, the presence of plastics in the oceans has sparked questions about the safety of seafood and aquaculture products for human consumption.
A recent study conducted by scientists from the University of Milan and ATS Milano-Città Metropolitana, based on fish harvested from open-sea aquaculture farms in the Mediterranean, reveals surprising data about the presence of plastics in two widely consumed fish species: gilthead sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax).
The researchers characterized the presence of plastics in different organs of gilthead sea bream and European sea bass.
Plastic Pollution in Fish
The study in question focused on characterizing the presence of plastics in various organs of sea bream and sea bass from open-sea aquaculture facilities in the Mediterranean, spanning Italy, Greece, and Turkey. The results are concerning, as 38% of the analyzed fish were found to contain plastics in their tissues, suggesting that plastic pollution is a widespread issue affecting these species in the Mediterranean region.
Comparing the two species, the study’s results show that 41% of gilthead sea bream and 35% of European sea bass were contaminated.
Geography and Plastic Pollution
An interesting aspect of this study is that it reveals geographical differences in fish plastic contamination. Fish analyzed in Turkey and Greece exhibited higher levels of contamination compared to those in Italy. However, no significant differences were found between the geographical areas, indicating that plastic pollution is a widespread problem throughout the Mediterranean region.
Accumulation of Plastics in Fish
The study’s findings indicate that plastics tend to accumulate primarily in the gastrointestinal tract of fish and, to a lesser extent, in the muscles, which represent the edible part of the fish. According to the collected data, the maximum amount of plastic in the muscles is 0.01 grams per gram of wet weight (w.w.), suggesting a low risk for consumers through fish consumption.
Composition of Detected Plastics
A significant portion of the plastics detected in the fish consists of human-origin cellulose-based fibers. Moreover, the analysis of polymer composition suggests that the plastics ingested by fish can have both land-based and pelagic origins. This indicates that plastic pollution may result from various practices, including aquaculture activities and terrestrial sources.
This study sheds light on the growing concern regarding plastic pollution in the fishing industry, especially in offshore aquaculture in the Mediterranean. Although plastics were found in a significant proportion of the analyzed fish, the amount detected in the edible portions is relatively low and does not appear to pose a significant risk to consumers.
“The results of this study confirm the bioavailability of plastics to farmed marine fish, highlighting the need for careful monitoring of this type of contamination,” conclude the researchers.
It is essential to continue researching and taking measures to address this issue and reduce the introduction of plastics into the oceans. This includes promoting more sustainable aquaculture practices and proper management of plastic waste in the fishing industry.
Public awareness and action are crucial to address plastic pollution in the oceans and ensure the safety of seafood products that reach our tables.
The study was funded by the University of Milan as part of the interdepartmental SEED 2019 project “MEDWAY—Microplastics in MEDiterranean fish: towards understanding their transfer from WAter system to edible parts as a critical issue for food safetY.”
Reference (open access)
Mosconi, G.; Panseri, S.; Magni, S.; Malandra, R.; D’Amato, A.; Carini, M.; Chiesa, L.; Della Torre, C. Plastic Contamination in Seabass and Seabream from Off-Shore Aquaculture Facilities from the Mediterranean Sea. J. Xenobiot. 2023, 13, 625-640. https://doi.org/10.3390/jox13040040