Phytoremediation

Abstract

Over centuries, human industrial, mining and military activities as well as farming and waste practices have contaminated large areas of developed countries with high concentrations of heavy metals and organic pollutants. In addition to their negative effects on ecosystems and other natural resources, these sites pose a great danger to public health, because pollutants can enter food through agricultural products or leach into drinking water (EC, 2002; EEA, 2003). In the EU alone, an estimated 52 million hectares—more than 16% of the total land area—are affected by some level of soil degradation. The largest and probably most heavily contaminated areas are found near industrialized regions in northwestern Europe, but many contaminated areas exist around most major European cities (EEA, 2003). There could be between 300,000 and 1.5 million of these sites in the EU (EC, 2002)—the uncertainty in this estimate is due to the lack of common definitions and a scarcity of accurate data on the size and the level of contamination of affected sites. > In the EU alone, an estimated 52 million hectares—more than 16% of the total land area—are affected by some level of soil degradation Cleaning up contaminated soil is a costly enterprise—the overall cost to remediate affected sites in the EU is estimated to be between €59 and €109 billion (EC, 2002). Furthermore, current methods of soil remediation do not really solve the problem. In Germany, for instance, only 30% of soils from contaminated sites are cleaned up in soil remediation facilities (SRU, 2004); the remaining soil must be stored in waste disposal facilities. This does not solve the problem, it merely transfers it to future generations. Obviously, there is an urgent need for alternative, cheap and efficient methods to clean up heavily contaminated industrial areas. This could be achieved by a relatively new technology …