Prevalence of Blood Lead Level (BLL) Among School Children in Evansville, Indiana, and Its Impact on School Performance

• Activity Number: 554
• Type: Contributed
• Date/Time: Wednesday, August 12, 2015 : 10:30 AM to 12:20 PM
• Sponsor: Section on Statistics in Epidemiology
• Author(s): Shailendra N. Banerjee* and Mary Jean Brown and Randal Young
• Companies: National Center for Environmental Health and National Center for Environmental Health and Agency for Toxic Substances and Disease Registry
• Keywords: Lead Exposure ; Blood Lead Level ; Surveillance ; School Level Performance

Abstract

Lead exposure in childhood causes many adverse health effects including learning disabilities. Studies indicate that even a moderate or low level of lead exposure among children contribute to low performance in school test results. The Lead Poisoning Prevention Program in Indiana conducted blood lead testing surveillance among children under 7 years old during 1992 to 2006, on a voluntary basis. We obtained blood lead surveillance data for children 5 years or less during 2001 to 2004, in Evansville, Indiana. School level performance data for children in 3rd grade during 2009-2012 in English and Math were also obtained. The lead surveillance data for children born during (2001-2004) was linked with the school performance data for (2009-2012), when these children were expected to be in grade 3. It was possible to connect the individual children with the corresponding schools by geocoding the students' home addresses. We were able to account for busing using bus company records. We then used mapping software (GIS) to overlay home addresses with school attendance zones. This created a multi-level data with blood lead level (BLL), age, sex, median income of families (from Census) at the individual level and performance score at school level. We performed a multivariate analysis with this data and found children's blood lead level significantly affected their school performance tests. Specifically, it was found that schools with average BLL of children in 3rd grade, greater than or equal to 5.2 ug/dL were 3.5 times more likely to have less than 75% passing rate than those with less than 5.2 ug/dL, adjusting for children's sex and income. Our study will be further expanded and other confounders like race will be considered.