Environmental lead-210 and bismuth-210 accrue selectively in the brain proteins in Alzheimer disease and brain lipids in Parkinson disease

We studied the occurrence of the environmental radon daughters, Po-210 (alp ha particles), and Bi-210 (beta particles), in the protein and lipid fracti ons of cortical gray and subcortical white matter from the frontal and temp oral lobes of human brains of persons with Alzheimer disease (AD), persons with Parkinson disease (PD), smokers, or persons with no previous evidence of clinical neurologic disease (controls). We found a 10-fold increase in P o-210 and Pb-210 radioactivity in the protein fraction from both the cortic al gray and subcortical white matter in AD and smokers, and a similar incre ase in the lipid fraction in PD. The pathognomonic distribution of the rado n daughters to the lipids in PD and to the proteins in AD was inferred to r eflect the increase of local chlorine availability to which radon daughters bound selectively. Cigarette smoking strongly increases radon daughter ret ention in the central nervous system.