STIRRING a white pigment into water on a sunny day may be all that's needed to get rid of the dangerous toxins produced by blue-green algae, say researchers in Scotland.
Cyanobacteria, as blue-green algae are also known, grow in freshwater all around the world. They produce a class of toxins called microcystins, which can lead to tumours in humans and, in rare instances, can cause death by acute poisoning.
"About 50 per cent of the time, big growths of algae are toxic," says Linda Lawton, a microbiologist at Robert Gordon University in Aberdeen. No conventional water treatment is effective against microcystins, she says.
Lawton, Peter Robertson and their colleagues looked at titanium dioxidea pigment used in white paint and sun creamswhich they already knew promoted the oxidation of a variety of organic compounds in bright light. They found that mixing a suspension of the white powder in water and shining ...
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