If you ever wonder why people in the USA (especially the older ones) are freaking crazy, here you go.
https://www.pnas.org/doi/10.1073/pnas.2118631119
Crazy ass lead poisoning
https://www.pnas.org/doi/10.1073/pnas.2118631119
Crazy ass lead poisoning
We estimate population-level effects on IQ loss and find that lead is responsible for the loss of 824,097,690 IQ points as of 2015.
BLLs greater than 5 µg/dL were nearly universal (>90%) among those born 1951 to 1980, while BLLs were considerably lower than 5 µg/dL among those born since 2001. The average lead-linked loss in cognitive ability was 2.6 IQ points per person as of 2015. This amounted to a total loss of 824,097,690 IQ points, disproportionately endured by those born between 1951 and 1980.
While these exposures were deemed harmless at the time, animal studies and epidemiological evidence accrued in the intervening years reveal that such exposures likely disrupted healthy development across multiple organ systems (particularly the brain, bone, and cardiovascular systems), resulting in subtle deficits to important outcomes, such as cognitive ability, fine motor skills, and emotional regulation (6), that may influence the trajectory of a person’s life (e.g., their educational attainment, health, wealth, and happiness). These deficits largely persist across time and, in some cases, worsen (7, 8) and are now hypothesized to put individuals at risk for difficult-to-treat chronic and age-related diseases, including cardiovascular disease and dementia (9–11).