Assessing the burden of disease: A systematic review and a framework to quantify health impacts of endocrine disrupting chemicals.

Abstract

Background: Exposure to endocrine-disrupting chemicals (EDCs) might pose significant health risks, including metabolic disorders such as obesity. However, current studies lack a standardised approach to assessing the environmental burden of disease (BoD) caused by EDCs. This gap limits the comparability of findings and their utility for policymaking. We addressed this gap by developing a systematic framework to estimate BoD attributable to EDCs.

Methods: We comprehensively reviewed methodologies used in BoD studies, focusing on hazardous chemicals. We incorporated insights from expert opinions and official reports, such as those by the World Health Organization, to identify best practices. These sources informed the design of our BoD framework. Comparative risk assessment (CRA) principles were central to our methodology, providing a structured approach to quantify the health impact of EDC exposure. The framework integrated established principles for BoD estimation and incorporated EDC-specific exposure considerations, including low-dose, chronic exposure and lifetime accumulation. We applied the framework to a case study examining obesity-related outcomes.

Results: Our systematic search identified significant variability in existing BoD methodologies, particularly in metrics such as disability-adjusted life years (DALYs), quality-adjusted life years (QALYs), and economic costs. We used these findings to design a framework that standardises BoD assessment for EDCs, enabling consistent and comparable results. The framework accounts for unique EDC mechanisms, such as long-term exposure and cumulative risks, and emphasises using DALYs to enhance comparability across studies. The case study demonstrated the framework's applicability by successfully evaluating obesity outcomes linked to EDC exposure. It also highlighted the challenges of limited data availability and the potential for policy-relevant insights.

Conclusions: This study introduces a novel framework for estimating the BoD attributable to EDC exposure. Our framework supports consistent and replicable assessments, enabling comparisons across exposures and health outcomes. It highlights the need for further research on underrepresented regions, emerging chemicals, and multi-chemical exposures. This framework provides a foundation for advancing research and informing strategies to reduce the global health burden of EDCs.