Destruction of estrogens using Fe-TAML/peroxide catalysis
Nancy W Shappell1, Melanie A Vrabel, Peter J Madsen
1Animal Metabolism Unit, Biosciences Research Laboratory, United States Department of Agriculture-Agricultural Research Service, 1605 Albrecht Boulevard, Fargo, North Dakota 58105, USA. nancy.shappell@ars.usda.gov
Environmental Science & Technology
|March 21, 2008
Summary
An iron-tetraamidomacrocyclic ligand (Fe-TAML) activator rapidly degrades endocrine disrupting chemicals like EE2 in water. This green chemistry approach effectively removes harmful estrogens from wastewater, protecting aquatic life.
Area of Science:
- Environmental Chemistry
- Green Chemistry
- Toxicology
Background:
- Endocrine disrupting chemicals (EDCs) interfere with hormonal processes, impacting organisms.
- 17alpha-ethinylestradiol (EE2), a common birth control pill ingredient, contributes significantly to environmental estrogenicity.
- Current wastewater treatment plants incompletely remove EDCs and natural estrogens from agricultural and municipal sources.
Purpose of the Study:
- To investigate an environmentally benign method for reducing EDCs in water.
- To evaluate the efficacy of an iron-tetraamidomacrocyclic ligand (Fe-TAML) activator in degrading natural and synthetic estrogens.
- To assess the reduction in estrogenic activity following treatment.
Main Methods:
- Utilized an iron-tetraamidomacrocyclic ligand (Fe-TAML) activator with hydrogen peroxide.
- Treated water samples containing 17alpha-ethinylestradiol (EE2) and other natural estrogens.
- Analyzed degradation rates using liquid chromatography tandem mass spectrometry (LC-MS/MS).
- Assessed estrogenic activity loss via E-Screen assay.
Main Results:
- Fe-TAML and hydrogen peroxide rapidly degraded target estrogens, including EE2, 17alpha-estradiol, 17beta-estradiol, estriol, and estrone.
- Apparent half-lives for these hormones were approximately 5 minutes.
- A concomitant loss of estrogenic activity was observed post-treatment.
Conclusions:
- Fe-TAML activators offer a promising green chemistry solution for removing potent EDCs from water.
- This method effectively reduces both natural and synthetic estrogenic compounds in agricultural and municipal effluent.
- The rapid degradation and loss of activity indicate a significant advancement in wastewater treatment for endocrine disruptors.
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