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[Blood lead levels and poor school performance among children in Mexico City]
Carlos R Leal-Escalante1, Mary Carmen Baltazar-Reyes, Montserrat Lino-González
1Secretaría de Salud del Estado de Sonora, México.
Objective:
To describe the relationship between blood lead levels (BLL) and poor school performance.
Material And Methods:
A cross-sectional study was carried out in 1996 among 792 schoolchildren aged 7-14 years, who attended the outpatient units of five pediatric hospitals of Mexico City. BLL was measured together with lead exposure and academic performance.
Results:
Reported BLL and geometric means (GM) were 8.6 microg/dL and 7.7 microg/dL, respectively. The main source of exposure was the use of glazed pottery (difference of use =-1.182; p = 0.000). Among schoolchildren who failed any school year, GM of the BLL was 8.1 microg/dL, compared with children who did not fail (GM = 7.6 microg/dL; p = 0.240). The risk of failing a school year between the 1st and 3rd grade with a BLL greater than 10 microg/dL was 1.73 (p = 0.012, IC 95% 1.13-2.66) and from 1st to 4th grade was 1.62 (p = 0.021, IC 95% 1.07-2.46).
Conclusions:
Blood lead levels, among other conditions, may contribute to the failure in school performance observed in the children participating in this study.
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