I am not sure it’s accurate to say that chronically increased blood levels of aluminum is the only way to cause brain problems. The reviews I linked in my other comment suggest that aluminum can affect brain function by:
Being carried to the brain by immune cell endocytosis.
Disrupting immune cell cross-talk with the CNS.
Rapidly crossing the incompletely developed neonate blood brain barrier before being cleared more slowly by incompletely developed neonate kidneys. Remember that the aluminum clearance data is from healthy adult males.
I am not sure it’s accurate to say that chronically increased blood levels of aluminum is the only way to cause brain problems. The reviews I linked in my other comment suggest that aluminum can affect brain function by:
Being carried to the brain by immune cell endocytosis.
Disrupting immune cell cross-talk with the CNS.
Rapidly crossing the incompletely developed neonate blood brain barrier before being cleared more slowly by incompletely developed neonate kidneys. Remember that the aluminum clearance data is from healthy adult males.