except the sentence I quoted from the report says it's talking about previous exposure in childhood. The original point I was responding to say half the population; children are less than a quarter of the population.
"...yesterday's children, who are victims of what we term legacy lead exposures. We estimate that over 170 million Americans alive today were exposed to high-lead levels in early childhood, several million of whom were exposed to five-plus times the current reference level"
"...yesterday's children, who are victims of what we term legacy lead exposures. We estimate that over 170 million Americans alive today were exposed to high-lead levels in early childhood, several million of whom were exposed to five-plus times the current reference level"