Unraveling the pervasive influence of brominated flame retardants on reproductive and developmental outcomes: A systematic review

Abstract

Brominated flame retardants are a class of chemical flame retardants containing bromine elements. Widely used in various consumer products to reduce fire hazards. However, the ubiquitous presence of BFRs in the environment and their potential to bioaccumulate in human tissues have raised concerns about their reproductive and developmental toxicity. This comprehensive review synthesizes the current epidemiological, in vivo, and in vitro evidence regarding the effects of both traditional and novel BFRs on reproductive and developmental health outcomes, where epidemiological studies have linked BFRs exposure to adverse neurodevelopmental, perinatal, and reproductive health consequences, while animal studies provide further insights into the impact of BFRs on parental and offspring health across mammalian and non-mammalian species. Cellular and molecular investigations have unraveled the mechanisms underlying BFRs-induced toxicity, including germ cell and zygote vulnerability, testicular toxicity, sperm quality alterations, and placental dysfunction. Furthermore, the interactive effects of BFRs with other environmental contaminants such as heavy metals, Polychlorinated Biphenyls, methylmercury, and Polyfluoroalkyl Substances have also been explored, which highlights the importance of mixture toxicology in assessing the risks associated with BFRs exposure. Despite the growing body of evidence, limitations in current research and challenges in extrapolating findings to human health risk assessment are discussed, along with recommendations for future research directions and risk management strategies. Based on which this review provides a comprehensive foundation for understanding the reproductive and developmental toxicity of BFRs and underscores the need for proactive measures to mitigate their adverse health effects and protect vulnerable populations.