The tiny water plant spirulina is known to yield a protein-rich nutritive supplement. Now scientists in Gujarat have found that it can also play a role in cleansing the environment. Researchers at Sardar Patel University in Vallabh Vidyanagar say that the blue-green algae, dead or alive, can soak up toxic heavy metals such as nickel, chromium and cadmium from industrial wastewater. “One gramme of spirulina can take up as much as 500 milligramme of nickel,” said lead researcher Arabinda Ray of the university’s chemistry department. In the case of other heavy metals, the efficiency was slightly lower. The scientists hope that spirulina will emerge as a strong candidate for detoxifying a large number of water bodies in the country where industries dump their effluent.

Tobacco not for all, say genes

A section of the Indian population may be genetically prone to developing oral and other cancers if they indulge in tobacco use, says a recent study. Researchers at the Indian Statistical Institute, Calcutta, have found that slower than normal activity of a combination of three studied genes in human beings enhances the risk of malignant tumour formation in tobacco users. Certain variants of the gene N-acetyl transferase 2 (or NAT2) lead to slow acetylation (introducing an acetyl group in an organic compound) of compounds such as heterocyclic and aromatic amines present in tobacco, making these compounds remain attached to the DNA. Generally, enzymes released by DNA repair genes such as XRCC1 and XDP remove these adducts so that the organ escapes malignancy. Population studies by the ISI scientists show that about 40 per cent of Indians have a NAT2 gene variant with slower acelytation capability, 20 and 15 per cent with less active XRCC1 and XPD genes respectively.