More U.S. children will be considered to have high levels of lead in their blood under the CDC's Oct. 28 blood lead reference value update.
The blood lead reference value is meant to identify children ages 1 to 5 with higher levels of lead in their blood compared to most children. Under the latest update, children with 3.5 micrograms or more of lead per deciliter of blood are considered to have elevated levels. The CDC introduced the reference value in 2012. At the time, the standard was 5 micrograms.
"The new lower blood level reference value of 3.5 [micrograms of lead per deciliter] means that more children could be identified as having lead exposure, allowing parents, doctors, public health officials and communities to act earlier to reduce the child's future exposure to lead," the agency said.
About 50.5 percent of U.S. children have detectable levels in their blood (1 microgram per deciliter), according to a recent study involving more than 1.1 million children. The same study found 1.9 percent (21,172 children) had elevated levels, which are known to affect cognitive development. The study was conducted before the CDC's recent update, meaning 5 micrograms or more of lead per deciliter of blood was considered elevated.
"No safe blood lead level in children has been identified, and even low levels of lead in blood have been shown to affect learning and academic achievement, and some effects may even be permanent," the CDC's update said.