Dental Amalgam-Derived Mercury in Wastewater: A Systematic Review of Environmental and Health Impacts, and Control Strategies Publisher



Mazloomian M ; Ghaneian MT ; Yazdi NB ; Ehrampoush MH ; Madadizadeh F ; Gholami M
Source: Journal of Environmental Health and Sustainable Development Published:2025

Abstract

Introduction: Dental amalgam, a mercury-based restorative material, is a significant point source of environmental mercury contamination in clinical wastewater. Mercury and other heavy metals from dental clinics enter wastewater systems untreated, posing risks to ecosystems and human health. This review uniquely bridges the critical gap between dental practice effluent pathways, quantitative environmental risk assessment, and practical evaluation of mitigation technologies. Methods and Methods: A comprehensive literature search was conducted using Scopus, Web of Science, PubMed/MEDLINE, and Embase for publications from 2000 to 2024. This review focused on studies quantifying mercury in dental wastewater and evaluated the effectiveness of containment, treatment, and policy measures. Results: The findings confirmed that dental clinics contribute substantially to mercury loads in wastewater, with a single chair releasing as much as 4.5 g/day. Reported mercury concentrations in dental effluent vary widely, ranging from 0.90 µg/L to 39 mg/L, reflecting differences in clinical practices and control measures. The primary mitigation technology is amalgam separators, which can remove more than 90% of amalgam particles and are increasingly required by regulations, such as the U.S. Environmental Protection Agency 2017. A multi-faceted approach combining separators, optimized chairside practices, waste segregation, and staff education is essential for effective management. Conclusion: Despite the declining use of dental amalgam, it remains an important environmental concern. Effective mitigation requires a combination of stringent policies, proven technologies, and professional stewardship. Future efforts should prioritize standardized monitoring, long-term performance data on control measures, and robust cost-benefit analyses to guide sustainable dental practices. © (2025), (Shahid Sadoughi University of Medical Sciences). All right reserved.