Working Paper: NBER ID: w23392
Authors: Anna Aizer; Janet Currie
Abstract: Using a unique dataset linking preschool blood lead levels (BLLs), birth, school, and detention data for 120,000 children born 1990-2004 in Rhode Island, we estimate the impact of lead on behavior: school suspensions and juvenile detention. We develop two instrumental variables approaches to deal with potential confounding from omitted variables and measurement error in lead. The first leverages the fact that we have multiple noisy measures for each child. The second exploits very local, within neighborhood, variation in lead exposure that derives from road proximity and the de-leading of gasoline. Both methods indicate that OLS considerably understates the negative effects of lead, suggesting that measurement error is more important than bias from omitted variables. A one-unit increase in lead increased the probability of suspension from school by 6.4-9.3 percent and the probability of detention by 27-74 percent, though the latter applies only to boys.
Keywords: lead exposure; juvenile delinquency; school suspensions; instrumental variables
JEL Codes: I24; J15; Q53; Q58
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| Measurement error (C20) | Understatement of negative effects of lead exposure (I12) |
| Omitted variable bias (C20) | Understatement of negative effects of lead exposure (I12) |
| Lead exposure (J82) | School suspension (I21) |
| Lead exposure (J82) | Juvenile detention (K40) |