Ray of hope

at the University of Zurich in Switzerland, Helmut Brandl and his colleagues of the Institute of Plant Biology have shown that the fungus, Aspergillus niger, can coax out most of the toxic metals from incinerator ash. This fungus usually produces citric acid for the foodstuff industry (New Scientist, Vol 152, No 2056).

Flyash from incinerators is usually buried in landfill sites because of contamination with metals such as lead, nickel and cadmium. The ash is first mixed with materials such as concrete to stop the metals from seeping into rivers and streams. But since the cost of landfills is rising, the search for alternatives is also intensifying.

It was found that Aspergillus niger took exactly a week to extract 80 to 100 per cent of the metals