Flint, Michigan recently called a state of emergency because the use of water from the Flint river as a public water source had caused a dangerous spike in blood lead levels.° It’s anticipated that this public policy disaster will cause cognitive impairment and possible behavioral problems in the kids affected; lawsuits are underway. But how does the amount of lead in children’s blood in Flint compare to what Generation X was exposed as a result of tailpipe emissions?
The answer is a bit shocking. The Flint emergency has been declared because for a brief period of time (a few months) over 7 percent of Flint’s children had levels in excess of 5µg/dL. That’s three times the current national rate.
Children under the age of five tend to have higher blood lead levels than other groups, as their bodies absorb much more of it.° The damage can last a lifetime, which is why in 2012, based on a review of recent research, the CDC set 5µg/dL as the level at which children should be entered into case management to prevent further exposure. About 2.5% of children nationally had this level of exposure from 2007 to 2010, although this level has decreased a bit since then.°
How do these Flint emergency levels (7% of children above the 5µg/dL level) compare to historical levels? Well, in 1970 the average preschooler had blood lead levels of 23µg/dL, four to five times above the danger level:
Moreover, these were not levels that children were exposed to for a month or two: this would have been exposure to lead at levels 4 to 5 times the recommended maximum over the child’s entire childhood.
Comparison with average rates (vs. dangerous level rates) is perhaps even more striking. The average blood lead level in a 1970 preschooler was about 10 times the average blood lead level today.