Miles, you're making a lot of unsupported assumptions (more on that below) and you're asking the wrong question here. I've spent the last 35 years studying and cleaning up hazardous waste sites and documenting their impacts on human health. Some of which have lead contamination. I've worked on sites with documented impacts to children. The reason the standard is lower for children and women of child bearing age is the effect of lead on developing brains. It has nothing to do with "intake" except that children will incidentally ingest more lead from playing in contaminated soil and eating things that adults don't.
ildren
IT HAS NOTHING TO DO WITH INTAKE EXCEPT FOR THE FACT THAT ANY INTAKE HAS BEEN FOUND TO BE HARMFUL.
When you can explain the biochemical differences and how the lead acts differently on one to the other Perhaps I would give you five minutes. As it is, the is no difference. The difference is that the effect is more readily apparent in children, not that the effect s different in adults. Adults suffer the same symptoms,
