The relationship between lead exposure and homicide.
BACKGROUND
Previous studies have suggested that excessive lead exposure is related to aggressive and violent behavior.


OBJECTIVE
To evaluate the association between estimated air lead concentrations and homicide rates.


METHODS
Cross-sectional ecological study.


METHODS
All counties in the contiguous 48 states of the United States. EXPOSURE MEASURE: Estimated air lead concentrations and blood lead levels.


METHODS
The homicide rate in each county.


RESULTS
Negative binomial regression was used to examine the relationship between air lead concentrations and the incidence of homicide across counties in the United States (N = 3111). After adjusting for sociologic confounding factors and 9 measures of air pollution, the only indictor of air pollution found to be associated with homicide rates was air lead concentration. Across all counties, estimated air lead concentrations ranged from 0 to 0.17 microg/m(3). The adjusted results suggest that the difference between the highest and lowest level of estimated air lead is associated with a homicide incidence rate ratio of 4.12 (95% confidence interval, 1.02-16.61).


CONCLUSIONS
The results of this study support recent findings that there is an association between lead exposure and violent behavior.
Stretesky
P B
PB
Department of Sociology, B258 Clark Bldg, Colorado State University, Fort Collins, CO 80523, USA. pstretes@lamar.colostate.edu
Lynch
M J
MJ
D000393:Air Pollutants / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000009:adverse effects / Q000706:statistics & numerical data*; D006708:Homicide / Q000706:statistics & numerical data*; D006801:Humans; D007854:Lead / Q000009:adverse effects*; D012044:Regression Analysis; D014481:United States
D000393:Air Pollutants; D007854:Lead