Sistemas de humedales para el manejo, tratamiento y mejoramiento de la calidad del agua - page 30

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Review on constructed wetlands for the removal of emerging organic micro-pollutants
P. N. Carvalho1, T. Lv 1, Y. Zhang1,2, C. A. Arias1, H. Brix1
1 Department of Bioscience, Aarhus University, Ole Worms Allé 1, Building 1135, 8000 Aarhus C,
Denmark
2 College of Life Science, South China Normal University, Guangzhou 510631, PR China
pedro.carvalho@biology.au.dk
Emerging contaminants are a vast group of multiclass chemicals defined as newly identified or
previously unrecognised pollutants. They include a long list of products of daily use, such as
pharmaceuticals and personal care products (PPCPs), surfactants and surfactant residues, gasoline
additives, brominated flame retardants, drinking water and swimming pool disinfection by-
products, nitrosamines, drugs of abuse and their metabolites, hormones and other endocrine
disrupting compounds, organophosphate flame-retardants and plasticisers, nanomaterials
(nanosilver and nanogold, fullerenes and other carbon-based nanomaterials), artificial sweeteners
(sucralose, acesulfame, saccharin, cyclamate, aspartame), perfluorinated compounds (PFOA,
PFOS, and others), polar pesticides and their degradation/transformation products, algal toxins,
siloxanes, perchlorate, benzotriazoles, and more(1).
Presently, most wastewater treatment plants (WWTPs) are considered a major source of several
different emerging micropollutants to the aquatic environment. Despite the low concentrations
usually found (from ng/L to µg/L level), concerns regarding their presence in the environment are
increasing. Additionally, no less important, may be the transformations that these compounds
may undergo in the environment or during treatment in WWTPs, resulting in a wider number of
unknown derivatives or transformation products (TPs)(1) . Therefore, development of innovative
approaches that ensure an efficient removal of these contaminants is crucial.
Constructed wetlands (CWs) have been researched in the last years as alternative and/or
additional treatment systems for removal of micro-pollutants, mainly PPCPs, from effluents(2-
5). The ability of CWs for the removal of pharmaceuticals is promising at both microcosm and
full-scale level. Nevertheless, more research on the efficiency of CWs for the removal of
emerging pollutants is needed to validate the use of this technology for the removal of different
families of compounds, other than PPCPs.
We surveyed the literature regarding emerging organic micro-pollutants and constructed wetlands
using the following keywords: “constructed wetlands” and “pesticides”; “surfactants”; “flame
retardants”; “illicit drugs”; “nitrosamines”; “artificial sweeteners”; “benzotriazoles”;
“perchlorate”; “perfluorinated compounds” and “plasticizers” to build a database with 182
scientific publications. Pharmaceutical compounds were not considered as recent review papers
(from 2014) have covered this topic extensively. From the built database, of which 72% of the
publications consider pesticides, the results presented in the publications were reviewed.
This communication intends to give an insight of the main achievements and current research
perspectives on CWs application for the removal of emerging organic micro-pollutants, other
than pharmaceuticals, from wastewaters.
Keywords: wastewater; emerging contaminants; micro-pollutants; constructed wetlands;