Copper May Actually Reduce EDC Toxicity, Study Says
Copper and other metals may reduce the toxicity and bioavailability of estrogenic and endocrine-disrupting compounds (EDCs) in sewage treatment plant effluents. This reduction can lead to less exposure of aquatic species and can lessen the presence of such compounds in drinking water. This finding is published in the latest issue of Environmental Toxicology and Chemistry.
The activity of estrogenic compounds is reduced by adsorption to suspended solids and dissolved organic matter, such as humic acids, which occur naturally in effluents and the environment. Because adsorption reduces the bioavailability of EDCs, it also reduces their toxicity.
This result has called into question whether other constituents of effluents and surface waters, such as metals, may also reduce the impact of EDCs on the environment. As an example, copper is commonly found in aquatic environments at parts-per-billion levels and can combine with various organic compounds. According to the study, estrogenic activities decreased with increasing copper concentrations. The resulting modification in the chemical structure caused a remarkable reduction in the binding affinity at estrogen receptor sites.
The study's researchers, led by Jong Yol Park, tested the endocrine-disrupting capability of well known EDCs in the presence of various concentrations of copper. These authors are the first to report that metals can interact with EDCs containing –OH groups, forming complexes with metals and, thereby, reducing estrogenic activities. Although the authors tested only copper, other metals such as zinc were present in effluents and surface waters and may also reduce the endocrine-disrupting properties of EDCs.
To read the entire study, visit http://www.allenpress.com/pdf/i1552-8618-27-3-535.pdf.
Environmental Toxicology and Chemistry is the monthly journal of the Society of Environmental Toxicology and Chemistry (SETAC).