Follow-up of Elevated Blood Lead Levels and Sources in Children at One and Six Years of Age in Benin: A Cohort Study

Abstract

Background/Aim: Lead has detrimental health effects on children including reduced cognitive and behavioural development. A high prevalence (58%) of elevated Blood Lead Levels (BLLs) (>50 µg/L) was observed in 685 one-year-old infants in semi-rural Benin in 2011-13. These children were reassessed in 2016-18 to assess sources of exposure and reductions in BLLs. Methods: BLLs were analyzed by inductively coupled plasma mass spectrometry (n=425). Sources were assessed through a questionnaire. BLLs and prevalence of elevated BLLs at six years of age are described and compared to BLLs measured in 2011-13. Multivariate linear and quantile regressions were conducted to determine associations between potential sources of lead and BLLs. Results: The prevalence of elevated BLLs (>50 µg/L) was 59.5% [GM 56.4 µg/L, 95% CI: 54.1 - 58.7] at six years of age compared to 54.8% [GM 56.5 µg/L, 95% CI: 53.4-59.6] at one year of age. The prevalence of children with BLLs >100 µg/L decreased from 14.4% at one year of age to 8.2% at six years of age (p<0.001). Consumption of peanuts was associated with an increment in BLLs both in the lowest (25th) and highest (90th) percentiles of BLLs. Consumption of bushmeat killed by lead bullets was associated with increments in the higher percentile (75th) of the distribution of the BLLs. Presence of activity with the potential use of lead in the house or neighbourhood was also associated with increased BLLs. These potential sources of lead were common: 10% reported eating peanuts more than once per month, almost 19% reported current meat consumption, and 14% reported the presence of activity with the potential use of lead. Conclusion: We confirm the persistently high prevalence of elevated BLLs in this rural, non-mining site, in south Benin. These results highlight the need for prevention strategies to decrease lead exposure in this population of children.