Fantastic article about the history of lead poisoning, and how hard it was for one researcher to get a hearing for the truth that lead in the atmosphere had gone way up with the use of leaded gasoline in cars, and this had serious health effects. Industry was left to do most of the research on lead, and they succeeded in co-opting government agencies who didn't realize that there was so much lead contamination everywhere, results were almost always flawed.
For children, lead may have lowered IQ by 5 points. The greatest harm probably came from eating and breathing lead from old paint. African-Americans were disproportionately affected in the U.S. IQ is not necessarily an important indicator of success in life.
What about life expectancy at birth in the U.S.? Did it go down noticeably during the lead-in-gasoline years, and then go up? Doesn't seem so.
You can actually notice the flu epidemic of 1919, which killed more people than the world war that had just ended. After that, men made much slower progress than women. One would think they were all breathing the same air. Men were more likely to pump gas, work on cars? I think smoking made more difference than anything else.
Men briefly hit 60 years in 1921, and there were three years there when men tied with women. Men didn't hit 60 or above again until 1932, and they weren't consistently in the 60s for some years after that. Women didn't go below 60 from 1930 on, having reached the 60s several times by then. Men didn't reach 70 until 1979, and didn't go below 70 after that. Women reached that milestone in 1949.
Progress has been steady in the post-lead years, but I would think no more so than in the many lead years. Surely there are many factors extending life expectancy. When the big magic bullets were arriving--antibiotics, vaccines--likelihood of reaching age 20 went up as children survived. Since then the likelihood of reaching 60, then 70, then 80 is up.
Of course homage is paid to Rachel Carson. Lead poisoning and mercury poisoning result from natural substances, but also from "industrial" processes in that we use materials in a way that greatly increases our exposure. Have any man-made chemicals actually caused cancer?
Benzidine, I guess.