Abstract: The present invention relates to the use of plants for the production of metal nanoparticles. In particular, precious metals such as gold, silver and platinum can be produced using plants such as alfalfa.

Abstract: Methods are described for the decontamination of soil containing heavy metals. In particular, these methods rely on phytoremediation using the plants of the species Larrea tridentata, the creosote bush. The methods are particularly directed at the decontamination of soil containing lead, copper, nickel and cadmium. The methods described herein are the first examples of phytoremediation using perennial plants which concentrate a high proportion of the scavenged metals in nonessential tissues, allowing the plants to be used continuously, rather than requiring repeated cycles of planting and harvesting entire plants in order to fully decontaminate the same area of land.