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Considering the increasing presence of the hormones levonorgestrel (LNG) and gestodene (GES) in wastewater, the limited effectiveness of conventional treatment methods, and the demand for advanced complementary processes, our study aimed to optimize an anodic oxidation treatment with a focus on low specific energy consumption (SEC) and costs. An electrochemical system coupled to a boron-doped diamond anode (BDD) was continuously used to treat synthetic and real pharmaceutical wastewater from contraceptive production. The central design composite and response surface methodology were the tools employed for optimization. The lowest SEC was obtained as a response to the main process variables: current density, initial pH, and the concentration of the support electrolyte ([Na 2 S 2 O 8 ]). The optimal condition ([Na 2 S 2 O 8 ] 0 = 0.07 mol L−1; [LNG] 0,RPW = 1.02±0.05 mg L−1 and [GES] 0,RPW = 1.05±0.05 mg L−1; j = 37.5 mA cm−2; pH = 6.75) was established considering an SEC ≤ 3.6 ± 0.8 kWh g−1 and progestins removal ≥70%, which was the experimental condition used to evaluate acute toxicity to Daphnia similis and the effect on estrogenic activity removal using the YES assay. Notably, our study evaluated, for the first time, a comparative investigation that highlights the substantial effect of support electrolytes over the eco-compatibility assessment of the anodic oxidation process investigated. The adaptability of the operation indicates the prospective suitability for the implementation of the process in wastewater treatment facilities in the pharmaceutical industry. [Display omitted] [ABSTRACT FROM AUTHOR]

Endocrine disrupting chemicals (EDC) are exogenous substances that can potentially mimic hormonal substances and cause adverse effects on the endocrine system of living beings. The behavior and fate of these compounds in the environment is directly related to their physical-chemical properties, which indicate great affinity for solid and organic particles and suggest an inherent mechanism of fractionation between dissolved and particulate phases of aqueous matrices. However, few studies have been considering this fact when quantifying these pollutants and their effects through bioassays. In this study, the fractionation of estrogenic substances between dissolved and particulate phases in an urban stream was investigated via estrogenic activity evaluation by the YES assay. Two fractions of suspended solids (< 0.7 µm and between 0.45 and 0.7 µm) and the dissolved phase were considered and two approaches of SPE percolations were applied. Total estradiol equivalent (E2-Eq) values were observed in the 29–65 ng L−1 range, of which 35–62% were associated with the particulate phase. Most of the estrogenicity was associated with particles between 0.45 and 0.7 µm, whereas cytotoxicity was induced by extracts of particles greater than 0.7 µm. Results demonstrated the importance of solid fractions analysis towards the quantification of total estrogenic activity from aqueous environmental matrices and highlights the relevance of controlling fine suspended solids in sewage treatment plant effluents, regarding the control of endocrine disrupters in the environment. ga1 • High level of total estrogenic activity was quantified up to 65 ng L−1. • Phase distribution of estrogenic activity was highly influenced by SPM profile. • Cytotoxicity was recurrently associated with particles > 0.7 µm. • SPM < 0.7 µm in wastewaters might be of great concern due to associated EDC. [ABSTRACT FROM AUTHOR]