The January 11 issue of Archives of Internal Medicine has reported a new study in which US researchers have noted that even an infinitesimal amount of lead in the body of children can have a damaging effect on the functioning of their kidneys.

The researchers said that US teenagers have small amounts of lead in their blood, largely due to exposure to things like lead paint in toys or walls, soil, glazed pottery, and even drinking water in some urban areas with old houses.

As such, the Centre for Disease Control and Prevention (CDC) had reduced ‘safe’ lead levels for children to 10 mg per tenth of a liter of blood or deciliter in 1991, from the earlier level of 30 micrograms (mg).

For the study, the researchers observed 769 healthy children and teens - aged between 12 and 20 years – who participated in the Third National Health and Nutrition Examination Survey conducted from 1988 to 1994. Upon the random assignment of the participants into four groups, the researchers found that the group reporting the highest lead levels proved to have slowing kidney function.

Commenting on the findings, lead researcher Dr. Jeffrey Fadrowski, of Johns Hopkins University in Baltimore, said the study shows that “very low levels of lead may impact kidney function in healthy children, which underscores the need to minimize sources of lead exposure.”