Abstract- Phytoremediation is widely viewed as an environmentally sound ... well as field experiments focussed on phytoremediation methodologies for.
FROM LABORATORY EXPERIMENTS TO LARGE SCALE APPLICATION – AN EXAMPLE OF THE PHYTOREMEDIATION OF RADIONUCLIDES
PETR SOUDEK, ŠÁRKA VALENOVÁ, DAGMAR BENEŠOVÁ AND TOMÁŠ VANċK Department of Plant Tissue Cultures, Institute of Organic Chemistry and Biochemistry, Czech Academy of Science, Flemingovo nám. 2, 166 10 – Prague 6, Czech Republic
*To whom correspondence should be addressed.
Abstract- Phytoremediation is widely viewed as an environmentally sound alternative to the destructive physical remediation methods currently practised. Plants have many endogenous genetic, biochemical, and physiological properties which make them ideal agents for soil and water remediation. Significant progress has been made in recent years in developing native or genetically modified plants for the remediation of contaminated environments. Because elements are chemically stable, phytoremediation strategies for radionuclide and heavy metal pollutants focus on above-ground hyper-accumulation. Soil contaminated with radionuclides pose a long-term radiation hazard to human health through exposure mainly via the food chain. Remediation of radionuclidecontaminated soils has become increasingly important. Removal of the contaminated surface soil (often down to 40cm) or immobilization of radionuclides in soil by applying mineral and chemical amendments are physically difficult and not cost-effective. Reducing plant uptake of radionuclides, especially 137Cs and 90Sr by the provision of competitive cations in chemical fertilizers is advantageous in large scale, low-level contamination incidents on arable land, and has been widely practised in Central and Western Europe following the Chernobyl accident. In this contribution we summarize results obtained from laboratory, greenhouse as well as field experiments focussed on phytoremediation methodologies for the removal of radionuclides from both the soil and the water.
139 N. Marmiroli et al. (eds.), Advanced Science and Technology for Biological Decontamination of Sites Affected by Chemical and Radiological Nuclear Agents, 139–158. © 2007 Springer.
140
P. SOUDEK ET AL.
Keywords: phytoremediation, radionuclides, 137-caesium, 90-strontium, 125iodine, uranium, radium, uranium mill tailings, biomonitoring
1. Introduction Radionuclides are high risk pollutants of significant impact to the environment, food chain and human health. The removal of radionuclides from the environment is important for human health because the ionizing radiation they emit is harmful. Large irradiation doses can cause extensive cellular damage and result in cell death, but even low levels of chronic exposure are known to be responsible for genetic changes, pre-cancerous lesions, benign tumours, cataracts, skin changes and congenital defects. Uranium ore processing factories, nuclear power plants, nuclear bomb testing areas and accidents in nuclear facilities have introduced large quantities of radionuclide into the environment. The Chernobyl accident in 1986 has resulted in long-term environmental radiological contamination throughout the whole of Europe, and the release of 134Cs and 137Cs (respectively, 54 and 85PBq) are the most important of these contaminants. The most highly contaminated areas are in the three former Soviet Union republics of Belarus, Ukraine and the Russian Federation, where an area of about 150,000km2 is contaminated at more than 1Ci/km2 (37kBq/m2). Substantial areas of other European countries have been similarly affected, e.g., Sweden (12,000km2), Finland (11,500km2), Austria (8,600km2), Norway (5,200km2) and Bulgaria (4,800km2), while lower activity (
