Estimating the global burden of disease of mild mental retardation and cardiovascular diseases from environmental lead exposure

The disease burden from exposure to lead resulting in mild mental retardation (due to IQ point decreases) and cardiovascular outcomes (due to increases in blood pressure) was estimated at a global level. Blood lead levels were compiled from the literature for 14 geographical regions defined by the World Health Organization according to location and adult and child mortality rates. Adjustments were applied to these levels, where appropriate, to account for recent changes relating to the implementation of lead-reduction programs and the lower levels seen in rural populations. It is estimated that mild mental retardation and cardiovascular outcomes resulting from exposure to lead amount to almost 1% of the global burden of disease, with the highest burden in developing regions. This estimate can be used to assess the magnitude of the benefits that could be accrued by increasing the global coverage of lead-reduction programs.