Lead contamination of Russian cities: Assessment of risk to children's health

Annual industrial lead releases into the air of Russian cities varies from 1.1 to 1.6 thousand tons. In spite of the substantial decrease of lead emissions in recent years, high levels of lead in the environment (PbE) are still measured. They create increased lead levels in human organisms and can cause various undesirable health consequences. Children are especially sensitive to lead contamination. Blood lead level (PbB) is often used as an indicator of the influence of lead on a child's health, and the acceptable level is 10 ug of Pb per 100ml of blood. The probability of exceeding this level of PbB defines the health risk. This paper presents general results of a health risk assessment of lead exposure in children living in Russian cities. The Integrated Exposure Uptake Biokinetic Model of the US EPA was used to predict total lead intake with pathway differentiation. The health risk of elevated PbB is based on monitoring data of PbE. Predicted model curves relating PbB to PbE can be used by decision-makers in forming environmental policy. Calculated PbB of children living in the cities with relatively low and moderate levels of PbE is close to the standard (10 ug/dl). In highly contaminated cities this standard can be exceeded by 100%. Estimated corresponding risk values are 50% and 85%. Analysis of the different contributing pathways for total lead exposure shows that the principal contributors are: first, food products; then soil/dust; with the lowest contributions from air and drinking water. An assessment of health consequences shows the following approximate distribution of hazard: two million children in Russian cities can have problems in behavior and learning; 400 thousand will need treatment; and the health of 10 thousand children is in danger while 400 children will need immediate hospitalization. These results lay a foundation for planning future studies (owing to the weakness of existing data), building short- and long-term environmental policy, and defining the most effective means to health risk reduction.