A Systematic Review on the Effects of Short-Term Exposure to Bisphenol-A and Bisphenol-S During Embryonic Stages of Zebrafish (Danio rerio)

Bisphenol-A is a highly used industrial chemical and a pervasive environmental oestrogen. Therefore, bisphenol-S was introduced as a safe alternative, yet endocrine disruption properties have been reported. Therefore, the safety of bisphenol-S as a safe substitute of bisphenol-A has become questionable. Yet, the existing published literature on comparative assessment of bisphenol effects are not conclusive. Therefore, a systematic review was carried out to comprehend the relative effects of bisphenols, by comparing the growth-related effects of early-life exposure to bisphenol-A and bisphenol-S in the model organism, Danio rerio (Zebrafish).  The review analysed the published research through Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) strategy. The search was conducted in Research Gate, Pub Med, Google Scholar, and Science Direct databases for articles published from the start of database coverage until August 2021, searching for articles on survival and growth-related effects of bisphenols in embryonic stages of zebrafish. Out of 181 articles, only 7 articles became eligible for inclusion criteria of early life (embryo) short-term bisphenol exposure. In recruited articles, hatching rate, body length, locomotion, malformations and survival of zebrafish were analysed under bisphenol concentrations of 0.0001 mg/L to 100mg/L. Studies on hatching rate have reported that exposure to both types of bisphenols in the concentration range of 1-100 µg/L significantly increase the hatching rate in a comparable manner. One study has reported that bisphenol-S significantly decreases embryo survival in lower concentrations than bisphenol-A. Decreased body length under the concentration range of 0.1-100 µg/L were evident for both bisphenols in a comparable manner. Based on the systematic review, it can be concluded that acute exposure to bisphenol-A and bisphenol-S exert similar effects to zebrafish embryos. Therefore the claim on the bisphenol-S as a safe bisphenol-A substitute warrants further investigations.