RESUMEN
The article deals with simple methods of decontamination of groundwater from the vicinity of brownfields contaminated with organic and inorganic substances. In the literature, thousands of articles on this issue at various sophisticated levels of knowledge can be found. The articles are mostly suitable as an extension of scientific knowledge; however, regarding potential costs and respectively scale-up problems, the applications are limited. It turns out that the vast majority of contaminated water can be effectively decontaminated by simple methods, in a coagulation-sedimentation sequence â simple oxidation and reduction methods for separated water (Fenton reaction, photocatalysis, ozonation, reductive dehalogenation with zero metals) â adsorption of remaining pollutants on simple sorbents, eg on biochar â (possibly bioremediation or advanced physical methods such as membrane filtration) â final purification on activated carbon. Due to the usually limited volume loads of soils with pollutants in the vicinity of brownfields, it is not economically advantageous to build demanding decontamination units for water purification. Usually, the simplest solution is the system to pump-and-treat around the source of contamination, with the main emphasis on highly effective removal of pollutants from water that returns underground. Groundwater was taken from boreholes leading to the saturated zone in the vicinity of several selected industrial brownfields. The solutions are shown on individual typical cases.
Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Biodegradación Ambiental , Contaminantes Químicos del Agua/análisisRESUMEN
Engineered nanoparticles (ENPs) exhibit unique properties advantageous in a number of applications, but they also represent potential health and environmental risks. In this study, we investigated the phytotoxic mechanism of CuO ENPs using transcriptomic analysis and compared this response with the response to CuO bulk particles and ionic Cu2+. Ionic Cu2+ at the concentration of 0.16 mg L-1 changed transcription of 2692 genes (p value of <0.001, fold change of ≥2) after 7 days of exposure, whereas CuO ENPs and bulk particles (both in the concentration of 10 mg L-1) altered the expression of 922 and 482 genes in Arabidopsis thaliana roots, respectively. The similarity between transcription profiles of plants exposed to ENPs and ionic Cu2+ indicated that the main factor in phytotoxicity was the release of Cu2+ ions from CuO ENPs after 7 days of exposure. The effect of Cu2+ ions was evident in all treatments, as indicated by the down-regulation of genes involved in metal homeostasis and transport and the up-regulation of oxidative stress response genes. ENPs were more soluble than bulk particles, resulting in the up-regulation of metallochaperone-like genes or the down-regulation of aquaporins and metal transmembrane transporters that was also characteristic for ionic Cu2+ exposure.