Environmental reproductive toxicity of common pesticides: Mechanisms and implications throughout the zebrafish life cycle

Reproductive toxicity is a significant factor contributing to the decline in population numbers and is increasingly being reported in association with pesticide exposure in ecological risk assessments. Pesticides can leach or spill into aquatic environments, where they remain suspended or settle, making aquatic organisms vulnerable to potential adverse effects. Although considerable progress has been made in studying the environmental impacts on reproductive health, there remains a need for comprehensive reviews detailing the complex relationships between reproductive toxicity and the structural characteristics of pesticides. The aim of this review is to summarize the diverse effects of various types of pesticides on the development and functionality of reproductive organs, gametes, embryos, and reproductive behaviors. This review discusses the potential mechanisms underlying these effects, such as disruptions to the hypothalamus-pituitary-gonad-liver (HPGL) axis, interference with steroid synthesis, DNA damage and methylation, inhibition of aromatase activity, as well as other detrimental impacts like oxidative stress and apoptosis. The interplay between these factors and the aforementioned mechanisms is intricate and can trigger a cascade of effects that ultimately compromise fertility and offspring viability. In summary, understanding how pesticides affect reproductive health in zebrafish will help us better protect aquatic ecosystems and, ultimately, human health. In addition to elucidating these mechanisms, understanding their interactions is crucial for the comprehensive assessment of reproductive toxicity.