Yeah, and so may have the alignment of Venus and Mars. That weasel-word "may" simply smashes any cogent argument to dust since the word is consistent with anything and is, hence, an untestable hypothesis.
The impact of chronic lead poisoning on the brain and nervous system is well-documented.
Actually for several years now, lead has been seen as a likely cause in the spike in violent crime in the 70s and 80s and why it’s gone down since the mid 90s.