Evaluation of the preliminary responses of Daphnia similis after prolonged exposure to contaminated food with different concentrations of microplastics (MPs)

Abstract

Microplastics (plastic particles < 5 mm in diameter) are ubiquitous in aquatic environments. This study aimed to evaluate the preliminary responses of Daphnia similis following the ingestion of Raphidocelis subcapitata algae contaminated with microplastics (5 mgL⁻¹, 50 mgL⁻¹, and 500 mgL⁻¹) over a 21-day period. Individuals exposed to the 5 mg·L⁻¹ microplastic treatment exhibited lower survival rates but produced a higher number of neonates per female. Adults exposed to the 5 and 50 mg·L⁻¹ treatments were smaller in size compared to those in the other treatments. These preliminary findings underscore the need for further research to better understand the chronic effects of microplastic exposure on freshwater organisms.