A small pilot study carried out by Prof Veen Kalra at the All India Institute of Medical Sciences (AIIMS) has revealed that a shocking 70 per cent of Delhi's school going children have unacceptably high levels of lead in their blood. Though the study involved only 200 children, it has for the first time confirmed what was suspected for a long time-chronic lead poisoning is quite widespread in India's metros. This could be quite a serious public health issue as a recent meta-analysis by Needleman et al has strongly suggested that intelligence quotient (IQ) levels can be shown to be inversely proportional to blood lead levels if other confounding variables are discounted. (Editorial.)