FYI, I'm a chiropractor and I strongly believe that everyone should receive all of their vaccinations.
The notion that babies immune systems will be overtaxed is absurd. 1st the virus and microorganism particles are attenuated or just pieces of the whole...not living. 2nd the second a baby is born it is exposed to about a trillion or so times more organisms than the shots it is about to receive. Study after study has found no link to autism or any harmful side effect, especially when compared to the risk of gettting the illness the shots are for!
If your kid gets a disease because you didn't vaccinate him/her you should be put in jail, especially if they wind up infecting others.
As for the additives...there isn't enough a.)at once b.) over a period of time to do damage. One friggin' crappy packed meal, water bottle, or outside harmful toxin (like smog or polluted water/fish) will probably triple the neurotoxicity of whatever is in the shot.
There are cases of harmful reactions, but given enough people, you'll find someone allergic to water.
Bottom line. Don't be an asshole, vaccinate your kids