Any candidate environmental factor also should be examined for differences in the level of exposure among the different study areas used in our analyses... The possibility of exposure to several environmental factors acting synergistically on susceptible populations also cannot be ruled out... Toxicological examination of any candidate environmental factor also would need to be conducted. Candidate factors would need to be disruptive to early human neural development, routes of exposure would need to be consistent with bioavailability to fetuses and infants, and the timing of increases in the production, use, or disposal of a factor resulting in human exposure would have to be consistent with our calculated changepoints and exposure gradients (McDonald, M., Paul, J., 2010).
Now they will say that 650 mcg of aluminum adjuvant is much higher then lets say Merck's PedvaxHIB Vaccines which contains 225 mcg of aluminum adjuvant, these vaccines are often given simultaneously with other aluminum containing vaccines. We know that the separate injection sites are not distinguished by the body. This is reiterated by this peer-review.
Shann, Frank, "The Nonspecific Effects of Vaccines and the Expanded Program on Immunization", The Journal Of Infectious Diseases, Vol 204, Issue 2, March 2011
"There is now clear evidence that the simplistic conventional model of immunization is invalid. We can no longer assume that a vaccine acts independently of other vaccines, or that it influences only infectious caused by the target disease."