According to a study, if you were born in the 60’s/70’s you lost your IQ because you were inhaling lead fumes. You can read more at Lead from gasoline blunted the IQ of about half the U.S. population, study says
Now can we draw any conclusions from this? People people believed as they did because of their lowered IQ. Perhaps they acted goofy and wore silly clothes because they weren’t thinking clearly. People made terrible decisions in those decades. Was the lead to blame? The answer seems to be “Yes” and you don’t need to consult a magic ball.
It is clear that the more industrialized we become, the more health hazards we face. You probably read that microplastics are everywhere even in newborns in the womb. How sad is that? For my part, I am avoiding plastics as much as possible. I try to use things that I can reuse like silicon bags, glass, or metal. Plus plastic always has a funny taste, and I never liked it. I tried to use glass and metal cups growing up as much as possible. The worst-tasting plastic was that we got from fast food. That always tasted terrible.
Does this mean that you are stupid if you were born in those decades? No, but you are dumber than you would be otherwise. A few points don’t mean much to the average person, but if you are on the low side it can slip you into the special education class. It limits your opportunities in life and for what? A smoother running engine? Something we could have avoided if we hadn’t sold the US to oil companies? The rich get richer while the poor get dumber? Is that the new slogan for the US?