Banning lead in gas worked. The proof is in our hair> Researchers analyzed samples of Utahns' hair going back a century to document a 100-fold decrease in lead concentrations.https://attheu.utah.edu/health-medicine/banning-lead-in-gas-worked-the-proof-is-in-our-hair/paper: https://www.pnas.org/doi/10.1073/pnas.2525498123#science #health #regulation