Effects of Petroleum and Bio-micro(nano)plastics on Aquatic Organisms

Plastics are integral to modern life but have led to significant environmental challenges, particularly in aquatic ecosystems, where micro(nano)plastics (MNPs) pose a growing concern. This chapter reviews the effects of both fossil- and bio-micro(nano)plastics on aquatic organisms, focusing on their ecotoxicological effects. While bioplastics are often marketed as eco-friendly alternatives, due to their expected biodegradability, emerging evidence indicates that these materials may degrade into micro- and nanoplastics and release harmful by-products such as additives, oligomers, and monomers. These degradation products have the potential to cause a wide range of pernicious effects on aquatic life. Overall, the available data show that bioplastics may exhibit similar or, in some cases, greater toxicity than fossil-based plastics. Furthermore, the incomplete biodegradation of bioplastics in natural environments may lead to persistent pollution, challenging their sustainability claims. The findings suggest a cautious approach to the widespread adoption of bioplastics, emphasizing the need for further investigation into their true environmental impact before they are considered a sustainable alternative to conventional fossil-based plastics. Key knowledge gaps are identified, particularly regarding the long-term impacts of micro(nano)bioplastics (MNBPs) on aquatic ecosystems and food webs. Future research should include the assessment of the effects of MNBP degradation products at environmentally relevant concentrations and how their effects may be modulated by climate change variables.