Mineralization of Steroidal Hormones by Biosolids in Wastewater Treatment Systems in Tennessee U.S.A.

Abstract

During the past several years, concern has risen over potential pollution of waterways with estrogenic compounds, including steroidal hormones from human and animal sources. One potential source of steroid hormone contamination is through the incomplete removal of these compounds in wastewater treatment systems (WTS). To address this issue, laboratory mineralization assays using 14C-labeled estrogens and testosterone were performed with biosolids from four municipal treatment plants and one industrial system. The importance of adapted microbial populations in the removal of estrogen was shown by the dramatic differences in mineralization of 14C-17β-estradiol by biosolids from a municipal plant compared to that from the industrial plant, 84% versus 4%, respectively. Indeed, biosolids from all of the municipal plants mineralized 70−80% of added 14C-17β-estradiol to 14CO2 in 24 h. Removal of 14C-17β-estradiol from the aqueous phase by biodegradation and/or biosorption to cell matter was greater than 90%. A r...