Petrol is getting cleaner. For mere 31 paise more a litre, Delhi is being supplied with petrol having 1 per cent benzene, thereby reducing the risk of Delhiities contracting leukemia or other lung diseases that are caused by this potential carcinogen. Mumbai will get low benzene petrol from January 1, 2001. Calcutta will follow two years later. However, low-benzene petrol alone is not good enough. The level of aromatics is yet to be lowered and some environmentalists point out that the benzene release from these aromatics may still keep the level of benzene in the atmosphere at dangerous levels. The Centre for Science and Environment (CSE) says that the level of aromatics is at 48 to 52 per cent compared with the world's best at 25 per cent. At 25 per cent, the level of benzene release into the atmosphere can be reduced by a further 42 per cent, CSE points out.