Ionic balance of unionid molluscs under diclofenac

This study is the first attempt to identify the possible effects of environmentally relevant concentrations of diclofenac (DCF) (0.1–1 μg/l) on the ability of freshwater bivalve molluscs to maintain the ionic balance of sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg) between the organism and the environment. The net ion flux between the organism of molluscs and the environment was assessed using deionized water. This approach made it possible to determine the minimum concentrations of various ions in the water (threshold concentration) that were necessary for the organism of molluscs to maintain a balance between the organism and the environment. 96 h exposure of the mollusc Unio pictorum to 0.1 and 1 μg/l of DCF resulted in damaging of its ability to maintain an ionic balance of Na, K, and Mg between the organism and the environment.