In conclusion, no significant differences in the metal concentrations between the autistic individuals and the control group could be observed. This result is rather surprising, as mercury and lead were in several publications found to be elevated in autistic individuals.
The reason, why I could not report significance might be a result of the low sample size or the investigation of metal levels in cord-blood and therefore corresponding rather to prenatal effects.

However, I found a tendency towards elevated levels of aluminum in autistic individuals. This tendency could further be validated by a Chi-Square test.
In scientific literature, aluminum was already occasionally reported to be elevated in autistic individuals. Another point of discussion might be the controversial role of vaccination in the development of autism. Many vaccines contain aluminum as adjuvant.
In this study, however, vaccination was not found to be the source for the elevated aluminum levels.