Elevated blood lead levels and sources of exposure in the population of Kinshasa, the capital of the Democratic Republic of Congo

Abstract

The objective of this study was to determine blood lead levels (BLLs) and the possible sources of exposure in the population of Kinshasa, the capital of the Democratic Republic of Congo. A cross-sectional survey was carried out from January to May 2008 in a representative sample of the Kinshasan population. BLL was measured in 275 individuals (53.4% women) aged 1-70 years in the urban area of Kinshasa and from 60 additional subjects in the rural area. Pb was also determined in environmental specimens (air and soil, indoor and outdoor). BLL in the study population ranged from 2.9 to 49.3 μg/dl (median, 9.9 μg/dl). The median BLL among children aged <6 years was 11.5 μg/dl (range: 3.0-37.8 μg/dl). Of these children, 71% had elevated BLL (≥10 μg/dl) and 22% had BLL ≥20 μg/dl. The proportion of elevated BLL (≥10 μg/dl) was higher for children aged <3 years than for children aged 3 to 5 years (97% vs 56%). A higher prevalence of elevated BLL was observed in urban compared with rural children (71% vs 20%). Significantly higher BLLs were also found in children whose mother consumed fired clay during pregnancy. Residential informal activities in the recycling of car batteries also contributed to elevated BLL in children. The elevated background of Pb exposure in the Kinshasan population indicates a public health issue that requires corrective actions. Pb-contaminated dust and air in children's home is an issue of public health concern. The use of leaded gasoline and the activities of car battery recycling in certain residences appear to constitute the main sources of exposure in the city of Kinshasa. The traditional use of fired clay for the treatment of gastritis by pregnant women is another significant contributor for elevated BLL in children.