Efficient water resources management in Cr(VI) impacted water bodies-POSTER SESSION

[CEST2019_00829] Effects of Cr(VI)-contaminated irrigation water on growth and development of selected crop species
by Georgiadou E.C., Zissimos A., Christoforou I., Christofi C., Fotopoulos V., Christou A.

Chromium (Cr) is a metal well-known to cause environmental pollution due to its association with a number of industrial processes involving leather, steel, electroplating, chemicals, dyes and paints. It is toxic to plants and microorganisms, and its study is attracting a lot of attention due to its increasing occurrence in groundwater under current changing climate scenaria. Of the several valence states of Cr, the trivalent [Cr(III)] and the hexavalent [Cr(VI)] species are the stable forms. Cr(VI) is considered as more toxic than the relatively innocuous and less mobile Cr(III), and is easily taken up by cells where it is subsequently reduced to Cr(III) and other intermediate oxidation states [Cr(V), (IV)] generating reactive oxygen species (ROS) in the process. A greenhouse experiment has been initiated at the Agricultural Research Institute aiming at evaluating the effects of various Cr(VI) concentrations in irrigation water on growth, development and yield of major cultivated crops, such as alfalfa, tomato, wheat and lettuce. Plants were irrigated with tap water spiked with Cr(VI) at concentrations of 0 (Control), 0.05, 0.5, 1, 5 and 10 mg L-1. Physiological processes and cellular damage levels were monitored in leaves by means of spectrophotometric determination of lipid peroxidation, chlorophyll loss and H2O2 content, further supported by stomatal conductance measurements, fresh/dry weight and SPAD units in leaves.

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Poster presentation in Efficient water resources management in Cr(VI) impacted water bodies-POSTER SESSION
[CEST2019_00768] Natural presence of hexavalent chromium in spring waters of South-West Mountain Vermion, Greece
by Stamos A., Samiotis G., Pekridis G., Tsioptsias C., Amanatidou E.

Hexavalent chromium in water occurs as oxoanions that are toxic for plants and animals. Furthermore, they are soluble and extremely mobile under environmental conditions. Chromium in its other common oxidative state (Cr+3) is less toxic and in general immobile. Chromium is found in nature mainly in the Cr+3 form. However, human activities and natural occurring Mn oxides that can oxidize Cr+3 to Cr+6, increase the concentration of the toxic form of Cr+6 in nature. The extended worldwide problem of Cr+6 pollution makes essential the understanding of the oxidation mechanism of Cr+3 from Mn oxides, for assessing the danger of Cr+3 oxidation as well as for developing processes to reduce its formation and presence. In this study, the natural occurrence of Cr+6 was examined in ground and surface waters of the South-West part of mountain Vermio (Kozani, Greece), an area where human activity is absent. The aim is to identify a natural background for Cr+6 concentration which can assist in legislation limit definition. Results show that in cases of waters exiting ophiolite or water permeable limestone having underlying layers of ophiolithic rocks, Cr+6 is detected. On the contrary when a thin layer of water impermeable schistolith interposes between limestone and ophiolite, then Cr+6 is not detected.

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Poster presentation in Efficient water resources management in Cr(VI) impacted water bodies-POSTER SESSION