Prevalence of Elevated Blood Lead Levels and Risk Factors Among Residents Younger Than 6 Years, Puerto Rico--2010.

CONTEXT: Limited data exist about blood lead levels (BLLs) and potential exposures among children living in Puerto Rico. The Puerto Rico Department of Health has no formal blood lead surveillance program. OBJECTIVES: We assessed the prevalence of elevated BLLs (≥5 micrograms of lead per deciliter of blood), evaluated household environmental lead levels, and risk factors for BLL among children younger than 6 years of age living in Puerto Rico in 2010. METHODS: We used a population-based, cross-sectional sampling strategy to enroll an island-representative sample of Puerto Rican children younger than 6 years. We estimated the island-wide weighted prevalence of elevated BLLs and conducted bivariable and multivariable linear regression analyses to ascertain risk factors for elevated BLLs. RESULTS: The analytic data set included 355 households and 439 children younger than 6 years throughout Puerto Rico. The weighted geometric mean BLL of children younger than 6 years was 1.57 µg/dL (95% confidence interval [CI], 1.27-1.88). The weighted prevalence of children younger than 6 years with BLLs of 5 µg/dL or more was 3.18% (95% CI, 0.93-5.43) and for BLLs of 10 µg/dL or more was 0.50% (95% CI, 0-1.31). Higher mean BLLs were significantly associated with data collection during the summer months, a lead-related activity or hobby of anyone in the residence, and maternal education of less than 12 years. Few environmental lead hazards were identified. CONCLUSIONS: The prevalence of elevated BLLs among Puerto Rican children younger than 6 years is comparable with the most recent (2007-2010) US national estimate (BLLs ≥5 µg/dL = 2.6% [95% CI = 1.6-4.0]). Our findings suggest that targeted screening of specific higher-risk groups of children younger than 6 years can replace island-wide or insurance-specific policies of mandatory blood lead testing in Puerto Rico.

Identifying housing that poisons: a critical step in eliminating childhood lead poisoning.

The purpose of our study was to develop a method to identify and prioritize "high-risk" buildings in Chicago that could be targeted for childhood lead poisoning prevention activities. We defined "high-risk" buildings as those where multiple children younger than 6 years with elevated blood lead levels (BLLs) had lived and where lead hazards were previously identified on environmental inspection. By linking 1997-2003 Chicago elevated blood lead surveillance, environmental inspection, and building footprint data, we found that 49,362 children younger than 6 years with elevated BLLs lived at 30,742 buildings. Of those, 67 were "high-risk" buildings and these were associated with 994 children with elevated BLLs. On average, 15 children with elevated BLLs had lived in each building (range: 10-53, median: 13). Almost two thirds (n = 43) of the high-risk buildings had two or more referrals for inspection to the same apartment or housing unit; of those, 40 percent (n = 17) failed to maintain lead-safe status after compliance. Linking blood lead surveillance, environmental inspection, and building footprint databases allowed us to identify individual high-risk buildings. This approach prioritizes lead hazard control efforts and may help health, housing, and environmental agencies in targeting limited resources to increase lead-safe housing for children.

Using geographic information systems to assess risk for elevated blood lead levels in children.

OBJECTIVES: Targeted screening for childhood lead poisoning depends on assessment of risk factors including housing age. Using a geographic information system (GIS), we aim to determine high-risk regions in Charleston County, South Carolina, to assist public health officials in developing targeted lead-screening. METHODS: Properties built before 1978 were geocoded (assigned latitude and longitude coordinates) from tax assessor data. Addresses of Charleston County children who have been screened for lead poisoning were also geocoded. Locations of all housing, lead poisoning cases, and negative screens were created as separate map layers. Prevalence ratios of lead poisoning cases were calculated, as were relative risks for each category of housing. RESULTS: Maps of Charleston County were produced showing the location of old housing, where screening took place, and where cases were found. One thousand forty-four cases were identified. Twenty percent of children living in pre-1950 homes had elevated blood lead levels (EBLL). Children living in pre-1950 housing were 3.9 times more likely to have an EBLL than children living in post-1977 housing. There was no difference in risk of living in a 1950-1977 home vs. a post-1977 home. A large number of cases were also found in an area of newer houses, but near a potential point source. Eighty-two percent of all screens were from children in post-1977 homes. CONCLUSIONS: Children living in pre-1950 housing were at higher risk for lead poisoning. GIS is useful in identifying areas of risk and unexpected clustering from potential point sources and may be useful for public health officials in developing targeted screening programs.

Blood lead levels and risk factors for lead poisoning among children in Jakarta, Indonesia.

The phase-out of leaded gasoline began in Jakarta, Indonesia on July 1, 2001. We evaluated mean blood lead levels (BLLs) and the prevalence of elevated BLLs of Jakarta school children and assessed risk factors for lead exposure in these children before the beginning of the phase-out activities. The study involved a population-based, cross-sectional blood lead survey that included capillary blood lead sampling and a brief questionnaire on risk factors for lead poisoning. A cluster survey design was used. Forty clusters, defined as primary schools in Jakarta, and 15 2nd- and 3rd-grade children in each cluster were randomly selected for participation in the study. The average age of children in this study was 8.6 years (range 6-12) and the geometric mean BLL of the children was 8.6 microg/dl (median: 8.6 microg/dl; range: 2.6-24.1 microg/dl) (n=397). Thirty-five percent of children had BLLs > or =10 microg/dl and 2.4% had BLLs > or =20 microg/dl. Approximately one-fourth of children had BLLs 10-14.9 microg/dl. In multivariate models, level of education of the child's primary caregiver, water collection method, home varnishing and occupational recycling of metals, other than lead, by a family member were predictors of log BLLs after adjustment for age and sex. BLLs of children who lived near a highway or major intersection were significantly higher than those of children who lived near a street with little or no traffic when level of education was not included in the model. Water collection method was a significant predictor of BLLs > or =10 microg/dl after adjustment for age and sex. BLLs in children in this study were moderately high and consistent with BLLs of children in other countries where leaded gasoline is used. With the phase-out of leaded gasoline, BLLs of children in Jakarta are expected to rapidly decline as they have in other countries that have phased lead out of gasoline.