Assessing potential toxicity of chloride-affected groundwater discharging to an urban stream using juvenile freshwater mussels (Lampsilis siliquoidea).

摘要: Abstract Groundwater contaminants, such as chloride from road salt, pose a threat to aquatic ecosystems when and where they discharge surface waters. Here we study the application of laboratory toxicity bioassay field-collected samples contaminated groundwater discharging an urban stream. The objectives were assess potential groundwater, while also exploring suitability standard tests site groundwater. Juvenile freshwater mussels chosen groundwater-appropriate (endobenthic) test organism. was sampled 6 sites at approximate depths 0, 10, 50 cm below sediment. Concentrations several metals above life guidelines in some samples. Exposure (96-h) resulted survival 90–100% 80–100% for 0-cm deeper samples, respectively, indicating that may toxicological mussels. Several with high had rate 80%, but generally there poor correlation between individual contaminants. Parallel juvenile mussel exposures using reconstituted water NaCl predicted natural 50% based on concentrations. This indicates protective ability possibly associated hardness. Finally, technical issues performing bioassays noted. First, aeration previously anoxic caused marked changes quality (especially metal concentrations). Second, calcite crystals formed shells elevated hardness, though no apparent negative effects.