ABSTRACT
As a vital part of the body, the nervous system is shielded from toxicants in the blood by a unique protective mechanism, namely, the blood-brain barrier (BBB) and blood-nerve barrier (BNB). Nonetheless, it is susceptible to a variety of toxicants. For example, methyl mercury affects mainly the nervous system, although its concentration in the brain is comparable to that in most other tissues, and in fact it is much lower than that in the liver and kidneys.
