The toxicity of pharmaceuticals finasteride (FIN) and melengestrol acetate (MGA) was assessed in freshwater mussels, including acute (48 h) aqueous tests with glochidia from Lampsilis siliquoidea, a sub-chronic (14 days) sediment test with gravid Lampsilis fasciola, chronic (28 days) sediment tests with juvenile L. siliquoidea, and in chronic (42 days) sediment tests with the amphipod Hyalella azteca and the mayfly Hexagenia spp. Testing with mussels assessed survival (glochidia, juvenile mussels), burial ability (juvenile mussels), and filtering and luring behaviour, and viability of brooding glochidia (gravid mussels). Testing with amphipods assessed survival, growth, reproduction and sex ratio. Testing with mayflies assessed survival and growth. Based on the limited number of measured environmental concentrations of both chemicals, and their projected concentrations, no direct effects are expected by these compounds individually on the invertebrates tested. However, organisms are exposed to contaminant mixtures in the aquatic environment, and thus, the effects of FIN and MGA as components of these mixtures require further investigation.
Results were published in a scientific article that can be found here: https://doi.org/10.1007/s11356-020-10121-7