Impacts of benzophenone-type UV filters on cladoceran Daphnia carinata

The impacts of three commonly used benzophenone-type UV filters including benzophenone (BP), 2-hydroxy-4-methoxy-benzophenone (BP3), and 2-hydroxy-4-methoxy-benzophenone-5-sulfonicacid (BP4) were assayed in vitro using a cladoceran Daphnia carinata. The 24-h LC50 on D. carinata calculated for BP, BP3, and BP4 was 8.37, 2.18, and 82.27 mg l−1, respectively. BP3 and BP4 significantly impacted on the time of D. carinata first molting at a concentration of 0.1 µg l−1. BP4 had an inhibitory effect on D. carinata molting and BP3 had an inhibitory effect on D. carinata pregnancy at a concentration of 1 µg l−1. Furthermore, BP4 significantly inhibited the number of D. carinata first brood per female at a concentration of 10 µg l−1. All of the endpoints from acute and chronic toxicity demonstrated that the hydroxy group in BP3 and BP4 significantly enhanced the toxic effect compared to BP. Therefore, the toxicity of BP-type UV filters is related to their molecular structure.