Effects of Different Polystyrene Concentrations on the Bioaccumulation of As, Cd, and Pb in Ruditapes Philippinarum

Abstract Microplastics constitute a new type of environmental pollutant with a particle size of less than 5 mm that can combine with heavy metals to enter organisms such as clams, and the impact of the combination of microplastics and heavy metals on the marine organism Ruditapes philippinarum remains unclear. Therefore, this problem is analyzed the effects of different concentrations (0, 0.1, 1, 5, and 10% w/w ) of polystyrene (PS) and three heavy metals (arsenic (As), cadmium (Cd), and lead (Pb)) (20 and 200 µg/L) on the bioaccumulation of the heavy metals in clams, and the effects of time for PS (0, 1, and 5%)-bound As, Cd, and Pb (ACP). We found that different concentrations of PS exerted different effects on the absorption of heavy metals by clams. A low concentration of PS (0.1%, 1%) inhibited heavy-metal bioaccumulation, while a high concentration of PS (5%, 10%) promoted their accumulation. Whether or not PS was added, the concentration of As, Cd, and Pb in clams increased with time. The relative amount bioaccumulated in clams was As > Cd > Pb, and we demonstrated a correlation between the concentration of heavy metals in clams and the concentration of PS in seawater. When exposed to a low concentration of PS, the concentrations of As and Cd in clams diminished with the concentration of PS in sea water; and when exposed to high concentrations of PS, the concentrations of Cd and Pb in clams appeared also to be reduced with increasing PS concentrations.