Variability in microplastic color preference and intake among selected marine and freshwater fish and crustaceans

Abstract

Plastic pollution is considered a pervasive global environmental challenge. Colored microplastics are prevalent in aquatic environments and the gastrointestinal tracts of wild-captured fish and crustaceans. Fish are thought to employ color vision to detect microplastics, prompting our investigation into microplastic ingestion patterns in three marine fish species, Chrysiptera cyanea, Hypoatherina tsurugae, and Plotosus japonicus, and three freshwater fish species, Rhodeus ocellatus, Pseudorasbora parva, and Misgurnus anguillicaudatus. Microplastics in red, blue, yellow, green, and gray were introduced to these species, and their ingestion was observed over a 4 h period under light conditions. Additionally, as crustaceans play an important role in connecting producers (phytoplankton) and consumers (fish) in natural ecosystems, we assessed a freshwater crustacean, Neocaridina denticulata. The crustacean did not ingest microplastics, and only 14% of P. parva individuals ingested microplastics (a proportion lower than that observed in the other fish species). Notably, C. cyanea, P. japonicus, and R. ocellatus exhibited color preferences in microplastic ingestion, with C. cyanea favoring red, P. japonicus preferring blue and gray, and R. ocellatus favoring red and yellow. Conversely, H. tsurugae, P. parva, and M. anguillicaudatus did not exhibit such color preferences. These findings suggest that certain fish use color vision to recognize and selectively ingest microplastics, with color preference being species-specific. Overall, this study provides new insights into microplastic ingestion by fish, potentially informing future toxicological assessments of microplastics in marine and freshwater fish and crustaceans intendan consumption.