Phytoremediation There is a lot of research on phytoremediation out there. Plants are used to pull all sorts of contaminants out of soils and water. Thlaspi caerulescens concentrates other metals as well - even uranium. (http://www.ars.usda.gov/is/AR/archive/jun00/soil0600.htm) I think there is a lot of potential for the use of plants to clean up our environment. Here is another interesting link about phytoremediation with links to current articles on the topic.