Fluoride toxicity and its effects on gametogenesis in the aquatic ologochaete Branchiura sowerbyi Beddard

B. sowerbyi is more resistant to fluorides than other freshwater invertebrates, especially at low temperatures. Accumulation is lower when the organisms are exposed to sodium fluoride in the absence of sediment, indicating that this animal also accumulates fluoride by ingesting sediment. Moreover, our study indicated that prolonged exposure to fluoride, even if at concentrations that had no effect in short or medium-term exposition, damages the gametogenetic cycle, particularly the spermatogenic one, preventing the reproduction of this species. The results revealed temporal differences in the gametogenic phases of the treated specimens such as incomplete spermatozoa maturation.