Air pollution causing Alzheimer's and Parkinson's disease ?

There is a finding that children in Mexico City are developing Alzheimer's and Parkinson's brain pathology due to the air pollution there:

http://www.ncbi.nlm.nih.gov/pubmed/23509683

And here is an article by the same author on how dark chocolate may be able to prevent it:

http://www.ncbi.nlm.nih.gov/pubmed/23986703