Cleaning up

Micro-organisms are miniature wizards in the art of removing toxic chemicals from oceans, rivers, and the soil. But they sometimes need a little help, and the technology of providing it is known as bioremediation. The efficacy of this approach to the cesspits of our industrial heritage has been shown at sites such as Greenbank, a grossly contaminated, derelict gasworks near Blackburn. A few years ago, bioremediators cleansed Greenbank of cyanides, phenolics, polyaromatic hydrocarbons, and other nasties simply by nourishing the microbes already present there.

But bioremediation is not being adopted as widely as some would wish. One reason is that regulatory …