heavy metals

Environmental contamination with heavy metals is often the result of various types of industrial processes. Because heavy metals can be dangerous to humans and other wildlife, contaminated sites need to be cleaned up. This isn't easy. Chemical extraction methods can introduce different types of pollutants into the environment.

Bioremediation -- using biological organisms to clean polluted areas -- is a hot area of research. Some plants can naturally sop up heavy metals without any ill effects, but plants don't always grow large enough to soak up all the pollution. Besides, plants can't be used to clean up contaminated water.

So, scientists have increasingly chosen to use the techniques of biotechnology to create genetically engineered microbes capable of gobbling up...