Estrogenic hormones (estrone, 17β-estradiol, estriol, 17α-ethinylestradiol) are the major contributor to the total estrogenicity in waterways. The presence of these compounds in biosolids is also causing concern in terms of their use as soil amendments.
In comparison with wastewater treatment, the removal of estrogenic compounds in sewage sludge has received less attention. This Canadian paper presents a literature review regarding the sources and occurrence of these pollutants in the environment.
The removal pathways of estrogenic compounds in engineered systems, such as full-scale wastewater treatment plants (WWTPs), are also discussed.
A review of the fate studies reveals that activated sludge systems with nutrient removal show very high (>90%) removal of estrogenic hormones in most cases.
Although aerobic digestion shows better attenuation of estrogenic compounds, anaerobic digestion increases the overall estrogenicity of biosolids.
The paper also highlights the challenges involved in analytical determination of these compounds in the sewage sludge matrix.
Water Research, Volume 46, Issue 18, 15 November 2012, Pages 5813–5833.
