Prior posts have noted a number of studies over recent years that have demonstrated the adverse impact of lead at levels below that traditionally considered as indicating "lead poisoning", 10 mcg/dL.
Lead poisoning continues to be a serious health problem for young children, especially those living in cities, so a government advisory committee is recommending that the definition of lead poisoning be changed to include a lower levels of exposure.
The current level set by CDC states that 10 micrograms of lead per dL of blood should be considered lead poisoning. [See http://www.cdc.gov/lead/.] At these levels, children may show symptoms such as abdominal pain, low appetite, difficulty sleeping, and constipation, as well as behavior or attention problems, hearing difficulties, and slower growth. Most of the adverse effects of lead on the brain and nervous system build over time, so these symptoms are difficult to pinpoint immediately after exposure.
An advisory committee to the CDC has reviewed the most recent data linking lead levels and developmental and physical problems in young children, and is now recommending that the definition of poisoning be changed to start at blood levels of 5 mcg/dL. This would mean that nearly a million children in the U.S. would be deemed to suffer from lead poisoning, approximately four-times the number deemed impacted under the current definition. The panel's advice follows that of a similar panel convened by FDA several days earlier, and that of the National Toxicology Program (part of HHS) which released a report in October. Both also recommended that lead poisoning be changed to include children with blood levels of 5 mcirogm/dL.
The CDC advisory commitee report can be found at http://www.cdc.gov/nceh/lead/ACCLPP/Final_Document_010412.pdf.