Treatment and Removal Strategies for Estrogens From Wastewater

Abstract

Natural and synthetic steroidal estrogens (estrone, 17 -estradiol and 17 -ethinylestradiol) are endocrine disrupters, that are discharged consistently from the sewage treatment works into surface waters, thereby causing endocrine disrupting effects to aquatic organisms at trace concentrations (nanogram per litre). Several years of research have been focused on their fate, behaviour and removal in the environment but primarily in the sewage treatment works which acts as a sink for these compounds. This review attempts to summarize the factors involved in the removal of these chemicals from the sewage treatment works. Biological processes, and to a limited extent physio-chemical properties, play a vital role in the endocrinal deactivation of these compounds. The efficiency of these processes is highly dependent on operating parameters (such as sludge retention time, redox potential, etc) that govern the secondary treatment process of a functional sewage treatment works. Although advanced treatment technologies are available, cost and operational considerations do not make them a sustainable solution.

The effectiveness of anaerobic digestion in removing estrogens and nonylphenol ethoxylates

“…Recently those organic micropollutants with endocrine disrupting ability have been the subject of major research investigations [2][3][4][5]. Endocrine disruption in fish has been predominantly attributed to the presences of free natural estrogens such as estrone (E1) and 17β-estradiol (E2) together with the synthetic estrogen 17α-ethinylestradiol (EE2) as well as nonylphenols (NP) and nonylphenol ethoxylates (NPEOs).…”

The fate and behavior of selected endocrine disrupting chemicals in full scale wastewater and sludge treatment unit processes

“…Thus the biodegradation of estrogens is well established (Stavrakis et al, 2008). However, currently wastewater treatment plants are not optimised to maximise estrogen removal (Koh et al, 2008) as they were not originally designed to remove EDCs and are just able to remove partly most of the EDCs (Janex-Habibi et al, 2009).…”

Caracterização de contaminantes presentes em sistemas de tratamento de esgotos, por cromatografia líquida acoplada à espectrometria de massas tandem em alta resolução

“…Percebe-se a formação do poluente ao longo do tratamento, uma vez que o nonilfenol é um subproduto da degradação de alquilfenóis polietoxilados presentes no esgoto domés-tico 20 (aumento de, aproximadamente, 127% em relação aos pontos extremos do sistema). De fato, a literatura 31,32 cita que, em condições anaeróbias, ocorre a progressiva diminuição do grau de etoxilação do nonilfenol etoxilado e consequente produção de nonilfenol.…”

“…19 Há vários estudos, feitos em outros países, mostrando que sistemas de tratamento biológico de esgotos não conseguem remover completamente compostos estrogênicos (ex., estradiol, estrona, etinilestradiol) capazes de alterar as funções endócrinas de animais aquáticos. 20,21 A maioria dos estudos relatados refere-se ao sistema de tratamento aeróbio conhecido como 'lodos ativados', de grande utilização no tratamento de esgoto sanitário nos países desenvolvidos.…”