A Systematic Review of Estrogens as Emerging Contaminants in Water: A Global Overview Study from the One Health Perspective.

The widespread presence of estrogens in aquatic environments represents a One Health concern, as it simultaneously threatens environmental integrity, wildlife health, and human well-being. These compounds, widely used in human and veterinary medicine, are excreted in partially or unmetabolized forms and persist in the environment due to the inefficiency of conventional water treatment systems in removing them. This systematic review provides a global overview of the occurrence of estrogens in water resources. We synthesized data on study characteristics, estrogen compounds detected, their concentrations, types of water bodies, and geographic locations. In total, 39 estrogens, including natural, synthetic, and metabolite forms, were reported at concentrations ranging from 0.002 to 10,380,000.0 ng/L across 40 water body types in 59 countries on all continents. The most frequently detected compounds were estrone, estradiol, and ethinylestradiol. Estrogens were predominantly identified in wastewater treatment plant effluents, rivers, lakes, surface waters, and even drinking water sources. These findings underscore the estrogen contamination and its potential to disrupt endocrine functions across species, posing serious implications for ecosystems. Within the One Health framework, this review highlights the urgent need for integrated strategies to improve water quality monitoring, develop advanced treatment technologies, and update regulatory standards to address the multifaceted risks posed by estrogenic contaminants.