Evaluation of on-site wastewater treatment technology to remove estrogens, nonylphenols, and estrogenic activity from wastewater.

A series of five on-site wastewater treatment systems were monitored for the removal of steroid estrogens, nonylphenols, and total estrogenic activity through several stages of pretreatment including aerobic and anaerobic sand filters. The objectives of this study were (1) to examine the ability of traditional septic systems and different types of pretreatment add-ons to remove nonylphenols (NPs) and the steroid estrogens estrone (E1), 17beta- estradiol (E2), estriol (E3), and 17alpha- ethinylestradiol (EE2) from the final effluent prior to discharge into the environment and (2) to examine the ability of each system and each stage of treatment within the system to remove total estrogenic activity as measured by a yeast estrogen screen (YES) assay. YES data and instrumental data are compared in the context of analyte recovery and estradiol equivalents. Results indicate excellent removal of NPs and total estrogenic activity to near or below detection limits when multiple stages of pretreatment including aerobic sand filters are used. However, only moderate removal of the steroid estrogens was observed through the anaerobic sand filters.