Bioaccumulation of Pharmaceutically Active Compounds from Treated Urban Wastewaters in Aquatic Insect Larvae and Aerial Adults

The bioaccumulation of 80 pharmaceutically active compounds (PhACs) was examined in larvae, pupae, and (sub)adults of three groups of aquatic insects (caddisflies Oligotricha striata and Limnephilus spp. and mayfly Siphlonurus aestivalis) reared in laboratory conditions, with their larvae exposed to a treated urban wastewater for up to 3 months and fed with uncontaminated food. The probability of PhAC detection (above limits of quantification) in larvae was relatively constant throughout the exposure time, while in adults, it was lower at the beginning with a subsequent increase. The total concentration of detected PhACs was highest in larvae of Limnephilus spp. and lowest in larvae of S. aestivalis, decreasing similarly in the adults of all three species. Significant differences in the composition of PhACs with different levels of changes after emergence were detected between species. Only telmisartan was detected in all species and life stages. Sertraline and its active metabolite norsertraline exhibited significantly higher relative concentrations in caddisfly adults compared to larvae. Apart from the bioconcentration factor, increasing biodegradation half-life was the second-best predictor of increased PhAC concentration in adults compared to larvae. At the same time, log Kow, commonly associated with bioaccumulation, was not found to be a good predictor of this relationship. The present study provides valuable insights into the bioaccumulation patterns and potential transfer of PhACs from aquatic to terrestrial ecosystems.