Programs to reduce lead levels in the soil in specific urban locations, and replace lead-painted windows in older homes, should be enacted.
Studies show early childhood exposure to lead at any level leads to decreased IQ and increased violent tendencies as an adult. This likely explains most of the increase in crime rates from the 1970s through the 1980s, when children exposed to high levels of lead in the 1950s and 60s became adults.
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Research also indicates that a $20bn/year investment over 20 years to replace lead-painted pre-1960s windows, and reduce lead concentrations in soil where deposits from leaded gasoline were highest, could yield a net positive $200bn/year return.