Brain Cancers and the Co-Carcinogenesis hypothesis

Francis Peyton Rous' Co-carcinogenesis hypothesis: that a virus and a carcinogen together cause cancer.

CMV (HHV5) and glioblastoma multiforme infection of glial cells
http://www.med.wisc.edu/news-events/new-evidence-links-virus-to-brain-cancer/32922
http://www.ncbi.nlm.nih.gov/pubmed/25699229

Craniopharyngioma and the herpes virus simplex (HHV2) infection of pituitary gland
http://www.ncbi.nlm.nih.gov/pubmed/18976107
http://www.ncbi.nlm.nih.gov/pubmed/8906037

Head and neck cancers and Epstein-barr virus (HHV 4) infection of squamous cells
http://www.infectagentscancer.com/content/pdf/1750-9378-8-7.pdf

The estrogen receptor of nerves cycles to the mitochondria but the estrogen receptors of adrenal cells like squamous cells cycle to the nucleus. Thus in nerves herpes breaks the mitochondria power house while in adrenal cells it destroys the nuclear cookbook.

Alzheimer's is herpes simplex (HHV1) infecting of the mitochondria of nerves thus destroying the nerves.
http://journal.frontiersin.org/article/10.3389/fnagi.2014.00202/full

Note that the virus alone does not cause cancer and that it needs a carcinogen. Co-carcinogenesis says both are needed.

 Imagine a virus as initially causing the DNA to replicate forever for it's own benefit.  Now imagine benzene which binds polymerases haulting copies.  Viruses have their own polymerases. Now imagine the carcinogen binds the viral polymerases better than the hosts.  So you have the cookbook of DNA open and no viral polymerase to compete with.

So what carcinogen gets into our brain?