Originally Posted by mrsD

There are biological toxins too:

Poorly cooked chicken can harbor Campylobacter bacteria, which attack the nerves (in addition to causing GI vomiting and diarrhea).

Also there is a fish poisoning:
http://en.wikipedia.org/wiki/Ciguatera

Also GBS from vaccine reactions.

These are the acute types, which may resolve and some of them are treated with IVIG.

The chronic ones, where the trigger is unknown present more difficulty since one may have continuous exposure.

What it amounts to is toxins are building up everywhere around us now. There is a very scary article out about Mexico City, and the nano particles concentrating there that are causing brain damage in CHILDREN (recently in Science News)!
http://www.nanowerk.com/news/newsid=12328.php

It is thought that pollution that we cannot see is affecting the brain, heart, and blood vessels of everyone exposed to it. It is not a stretch to include the nervous system too.