Scientific Contributions

 The contamination of marine ecosystems by microplastics constitutes a pressing environmental threat. This study aims to evaluate and compare potential hazards posed by individual and combined microplastics on filter-feeding microcrustacean, Artemia (A) salina. With the recognition of a vast array of microplastics present in the environment, the current study specifically investigated the impact of a triad of prominent microplastics, polypropylene (PP), low-density polyethylene (LDPE), and high-density polyethylene (HDPE), on the survival, bioaccumulation, and swimming behavior of A. salina under both mono- and co-exposure conditions. The research findings unveil significant differences in the lethal concentration (LC50) values of individual microplastics. PP, HDPE, and LDPE exhibited LC50 values of 124, 107, and 103 mg/L, respectively. Intriguingly, when all three microplastics co-existed, a marked decrease in the LC50 value to 68.2 mg/L was observed, indicating heightened mortality resulting from the compounded stress imposed by these polymers. Swimming declined significantly at higher microplastic concentrations in both mono and co-exposure modes; however, the impacts were adverse under co-exposure conditions. Bioaccumulation analysis revealed that microplastic accumulation in A. salina is dependent upon exposure concentration. These results highlight the increased ecological risk posed by combined microplastic exposures. These findings are also more relevant to real-time environmental conditions where co-exposure dominantly takes place.