The toxicity of waterborne boron to Daphnia magna and Chironomus decorus and the effects of water hardness and sulfate on boron toxicity

摘要: The concentrations of many elements, including boron, are increasing in aquatic ecosystems due to anthropogenic activities. Laboratory studies were undertaken evaluate the toxicity waterborne boron two key fresh water macroinvertebrates and effects hardness sulfate on toxicity. Acute evaluations sodium tetraborate resulted 48 h. LC50 values 141 1376 mg B/L for neonateDaphnia magna fourth instarChironomus decorus, respectively. Chronic sublethal demonstrated a significant decrease inC. decorus growth rate at 20 B/L. Further showed that (10.6 170 mg/L as CaCO3) (10.2 325.4 SO4−1/L) did not affect toD. magna. These results, conjunction with review literature, suggest macrophytes may be more sensitive than thus would better choices risk assessment this element.