Fate and levels of steroid oestrogens and androgens in waste stabilisation ponds: quantification by liquid chromatography-tandem mass spectrometry

Environmental fate and toxicity of androgens: A critical review

Androgens are released by humans and livestock into the environment and which cause potent endocrine disruptions even at nanogram per liter levels. In this article, we reviewed updated research results on the structure, source, distribution characteristics and the fate of androgens in ecological systems; and emphasized the potential risk of androgens in aquatic organism. Androgens have moderately solubility in water (23.6-58.4 mg/L) and moderately hydrophobic (log Kow 2.75-4.40). The concentration of androgens in surface waters were mostly in ng/L ranges. The removal efficiencies of main wastewater treatment processes were about 70-100%, except oxidation ditch and stabilization ponds. Sludge adsorption and microbial degradation play important role in the androgens remove. The conjugated androgens were transformed into free androgens in environmental matrices. Global efforts to provide more toxicity data and establish standard monitoring methods need a revisit. Of the day available, there is an urgent need for comprehensive consideration of the impact of androgens on the environment and ecology.

Occurrence and removal of micropollutants in full-scale aerobic, anaerobic and facultative wastewater treatment plants in Brazil

This study aims to evaluate micropollutant occurrence and removal in a low-middle income country (LMIC) by investigating the occurrence of 28 chemicals from different classes (triclosan, 15 polycyclic aromatic hydrocarbons (PAHs), 4 estrogens and 8 polybrominated diphenyl ether (PBDE) congeners) in three technologically diverse full-scale Brazilian wastewater treatment plants (WWTPs). These chemicals were detected at concentrations similar to those reported in other low-middle income countries (LMICs) and high-income countries (HICs) (0.1-49 μg/L) indicating their widespread use globally and the need for more studies in LMICs that are typically characterized by relatively inadequate wastewater treatment barriers. Among the three different WWTPs investigated for removal of these chemicals, the least energy intensive system, waste stabilization ponds (WSPs), was the most effective (95-99%) compared to the activated sludge (79-94%), and Up-flow sludge blanket reactor (UASB) with trickling filters system (89-95%). These results highlight the potential of WSPs for micropollutant removal-especially in warm climates. However, the effluent from all three WWTP could pose a risk to aquatic organisms when discharged into the receiving waters as the effluent concentrations of triclosan, some estrogens, PAHs and BDE 209 were above European environmental quality standards (EQS) or predicted no effect concentration (PNEC values), indicating that receiving water bodies could benefit from further treatment. In combination, these results help to further understand prevailing concentrations of micropollutants globally and fate in current wastewater treatment systems.

Pharmaceutical and personal care product residues in a macrophyte pond-constructed wetland treating wastewater from a university campus: Presence, removal and ecological risk assessment

Pharmaceuticals and personal care products (PPCPs) constitute a group of chemicals of concern because of their potential toxicity when reaching aquatic environments. Wastewaters are one of the main pathways of introduction into the environment of the chemical compounds used in PPCPs because, in most cases, wastewater treatment facilities are not 100% efficient in their removal. This problem is accentuated in rural zones and isolated communities where conventional treatment systems are too expensive to build and operate. Waste-stabilization ponds and constructed wetlands (CWs) are natural wastewater treatment systems which are used to improve the quality of sewage from small communities because of their low cost and easy maintenance. There is growing interest in combining the two technologies to make a more robust system, taking into account their respective strengths and weaknesses. In this work, a combined macrophyte pond-CW system was evaluated for the presence at three sampling points (influent, pond effluent and CW effluent) of fifteen steroid hormones and six benzotriazole ultraviolet stabilizers (BUVSs). None of the targeted BUVS compounds were detected in either the influent or effluent, probably because of the particular characteristics of the population served by the wastewater system. In contrast, eight different steroid hormone compounds were detected at concentrations ranging from 17.3 to 247.7 ng·L^-1 in influent samples and from 8.1 to 22.1 ng·L^-1 in final effluent samples. The pond-CW system showed high elimination rates of steroid hormone residues with average removal efficiencies of over 77%. This efficacy was confirmed in the ecological risk assessment evaluation that was performed. Final effluents showed a low ecological risk associated with steroid hormones in contrast to the medium-high ecological risks found in the influent samples.

Removal of organic micropollutants in waste stabilisation ponds: A review

As climate change and water scarcity continue to be of concern, reuse of treated wastewater is an important water management strategy in many parts of the world, particularly in developing countries and remote communities. Many countries, especially in remote regional areas, use waste stabilisation ponds (WSPs) to treat domestic wastewater for a variety of end uses, including using the treated wastewater for irrigation of public spaces (e.g. parks and ovals) or for crop irrigation. Thus, it is vital that the resulting effluent meets the required quality for beneficial reuse. In this paper, both the performance of WSPs in the removal of organic micropollutants, and the mechanisms of removal, are reviewed. The performance of WSPs in the removal of organic micropollutants was found to be highly variable and influenced by many factors, such as the type and configuration of the ponds, the operational parameters of the treatment plant, the wastewater quality, environmental factors (e.g. sunlight, temperature, redox conditions and pH) and the characteristics of the pollutant. The removal of organic micropollutants from WSPs has been attributed to biodegradation, photodegradation and sorption processes, the majority of which occur in the initial treatment stages (e.g. in the anaerobic or facultative ponds). Out of the many hundreds of organic micropollutants identified in wastewater, only a limited number (40) have been studied in WSPs, with the majority of these pollutants being pharmaceuticals, personal care products and endocrine disrupting compounds. Thus, future research on the fate of organic micropollutants in WSPs should encompass a broader range of micropollutants and include emerging organic pollutants, such as illicit drugs and perfluorinated compounds. Further research is also needed on the formation and toxicity of transformation products from organic micropollutants in WSPs, since the transformation products of some organic micropollutants can be more toxic than the parent compound. Combining other wastewater treatment processes with WSPs for removal of recalcitrant organic micropollutants should also be considered.

Occurrence and removal of estrogens in Brazilian wastewater treatment plants

This paper evaluated the occurrence and removal efficiency of four estrogenic hormones in five biological wastewater treatment plants (WWTPs), located in the State of Ceará, Brazil. The five WWTPs comprised: two systems consisted of one facultative pond followed by two maturation ponds, one facultative pond, one activated sludge (AS) system followed by a chlorination step, and one upflow anaerobic sludge blanket (UASB) reactor followed by a chlorination step. Estrogen occurrence showed a wide variation among the analyzed influent and effluent samples. Estrone (E1) showed the highest occurrence in the influent (76%), whereas both 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) presented a 52% occurrence, and the compound 17β-estradiol 17-acetate (E2-17A), a 32% one. The occurrence in the effluent samples was 48% for E1, 28% for E2, 12% for E2-17A, and 40% for EE2. The highest concentrations of E1 and EE2 hormones in the influent were 3050 and 3180 ng L(-1), respectively, whereas E2 and E2-17A had maximum concentrations of 776 and 2300 ng L(-1), respectively. The lowest efficiencies for the removal of estrogenic hormones were found in WWTP consisted of waste stabilization ponds, ranging from 54 to 79.9%. The high-rate systems (AS and UASB), which have chlorination as post-treatment, presented removal efficiencies of approximately 95%.

Analysis of bisphenol A, nonylphenol, and natural estrogens in vegetables and fruits using gas chromatography-tandem mass spectrometry

Bisphenol A (BPA), nonylphenol (NP), and steroidal estrogens in vegetables and fruits were analyzed using gas chromatography with tandem mass spectrometry (GC-MS/MS). Isotope dilution standards were spiked before the extraction to account for extraction inefficiency and loss of analytes during sample workup. Recoveries were >90% for all of the compounds in each matrix. The limit of detection (LOD) ranged from 0.03 to 0.3 μg kg(-1), whereas the limit of quantitation (LOQ) ranged from 0.1 to 1.0 μg kg(-1). All analytes can be monitored in a single GC-MS/MS run with a run time of 20 min. Occurrence of these endocrine-disrupting chemicals (EDCs) in vegetables and fruits from local markets was observed using the established analytical method. BPA was detected in all vegetable and fruit samples, ranging from 0.2 ± 0.1 to 9.0 ± 4.9 μg kg(-1), indicating significant exposure potential for humans. NP was detected in pumpkin, sweet potato, citrus, and apple samples. The concentration of 4-n-NP ranged from 5.3 ± 2.4 to 18.9 ± 8.0 μg kg(-1), whereas that of 4-NP ranged from 5.1 ± 2.6 to 12.2 ± 3.6 μg kg(-1). Concentrations of 17-β-estradiol in vegetables and fruits ranged from 1.3 ± 0.4 to 2.2 ± 1.0 μg kg(-1) except those in tomato and strawberry, in which no 17-β-estradiol was detected. The estimated daily intake of 17-β-estradiol was beyond the recommended acceptable daily intake (ADI) for children as recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA).