The research

The data behind what's at stake for your grandchildren

This is not opinion. These numbers come from NHANES, the largest ongoing health survey in the United States, plus peer-reviewed studies with combined sample sizes over 500,000 people.

0
million IQ points erased from the US population by leaded gasoline (McFarland 2022, PNAS)
0
times more likely to be diagnosed with ADHD at the highest blood lead levels (Braun 2006, n=8,413)
5x
the CDC safe reference level: what the average US child had in their blood in 1970 from leaded gasoline
Lead in US children's blood, 1925-2020
Geometric mean µg/dL for US children 1-5 (NHANES CDC) and tetraethyl lead added to US gasoline (EPA). Press play to watch 95 years of data draw in.
1925
Lead exposure and ADHD diagnosis odds
Braun et al. 2006, NHANES. Adjusted for income, parental education, home environment. The effect is dose-dependent.
Low blood lead (<2 µg/dL)1.0x baseline
Moderate (2-5 µg/dL)2.3x
High blood lead (top quintile >5 µg/dL)4.1x
Source: Braun JM et al., Environ Health Perspect 2006. Mendelian randomization confirmation: Nigg JT et al., Psychol Sci 2016.