Chronic zebrafish low dose decabrominated diphenyl ether (BDE-209) exposure affected parental gonad development and locomotion in F1 offspring

Polybrominated diphenyl ethers (PBDEs) are widely used as flame retardants around the world. Because of large production volumes, widespread usage and persistence, PBDEs are now ubiquitous environmental pollutants detected in a wide variety of environment media and human samples and therefore pose a significant public health concern. Deca-PBDE (BDE-209) is the only commercial PBDE mixture still allowed for use at present, and has been recently detected at high levels in human samples. However, few studies explore its effect on development, reproduction or neurobehavior with animal models. In particular, studies with long-term chronic exposure at relatively low doses are lacking. In this study, we utilize the zebrafish model to explore the developmental, reproductive, and behavioral toxicities associated with long-term chronic exposure to deca-PBDE (BDE-209). Our findings revealed that long-term chronic exposure to low dose of deca-BDE (ranging from 0.001 to 1 μM) affected overall fitness (measured by condition factor), gonad development, male gamete quantity and quality in F0 parental fish. For F1 offspring without continuous exposure to BDE-209, parental BDE treatment led to delayed hatch and motor neuron development, loose muscle fiber, slow locomotion behavior in normal conditions, and hyperactivity when subjected to light–dark photoperiod stimulation. In conclusion, parental chronic low dose BDE-209 exposure not only affects F0 growth and reproduction, but also elicits neurobehavior alternations in F1 offspring.