Jyothi Nagaraja

Exposure of U.S. children to residential dust lead, 1999-2004: II. The contribution of lead-contaminated dust to children's blood lead levels.

Background The U.S. Centers for Disease Control and Prevention collected health, housing, and environmental data in a single integrated national survey for the first time in the United States in 1999–2004. Objectives We aimed to determine how floor dust lead (PbD) loadings and other housing factors influence childhood blood lead (PbB) levels and lead poisoning. Methods We analyzed data from the 1999–2004 National Health and Nutrition Examination Survey (NHANES), including 2,155 children 12–60 months of age with PbB and PbD measurements. We used linear and logistic regression models to predict log-transformed PbB and the odds that PbB was ≥ 5 and ≥ 10 μg/dL at a range of floor PbD. Results The population-weighted geometric mean (GM) PbB was 2.0 μg/dL (geometric standard error = 1.0). Age of child, race/ethnicity, serum cotinine concentration, poverty-to-income ratio, country of birth, year of building construction, floor PbD by floor surface and condition, windowsill PbD, presence of deteriorated paint, home-apartment type, smoking in the home, and recent renovation were significant predictors in either the linear model [the proportion of variability in the dependent variable accounted for by the model (R2) = 40%] or logistic model for 10 μg/dL (R2 = 5%). At floor PbD = 12 μg/ft2, the models predict that 4.6% of children living in homes constructed before 1978 have PbB ≥ 10 μg/dL, 27% have PbB ≥ 5 μg/dL, and the GM PbB is 3.9 μg/dL. Conclusions Lowering the floor PbD standard below the current standard of 40 μg/ft2 would protect more children from elevated PbB.

Exposure of U.S. Children to Residential Dust Lead, 1999–2004: I. Housing and Demographic Factors

Background Lead-contaminated house dust is a major source of lead exposure for children in the United States. In 1999–2004, the National Health and Nutrition Examination Survey (NHANES) collected dust lead (PbD) loading samples from the homes of children 12–60 months of age. Objectives In this study we aimed to compare national PbD levels with existing health-based standards and to identify housing and demographic factors associated with floor and windowsill PbD. Methods We used NHANES PbD data (n = 2,065 from floors and n = 1,618 from windowsills) and covariates to construct linear and logistic regression models. Results The population-weighted geometric mean floor and windowsill PbD were 0.5 μg/ft2 [geometric standard error (GSE) = 1.0] and 7.6 μg/ft2 (GSE = 1.0), respectively. Only 0.16% of the floors and 4.0% of the sills had PbD at or above current federal standards of 40 and 250 μg/ft2, respectively. Income, race/ethnicity, floor surface/condition, windowsill PbD, year of construction, recent renovation, smoking, and survey year were significant predictors of floor PbD [the proportion of variability in the dependent variable accounted for by the model (R2) = 35%]. A similar set of predictors plus the presence of large areas of exterior deteriorated paint in pre-1950 homes and the presence of interior deteriorated paint explained 20% of the variability in sill PbD. A companion article [Dixon et al. Environ Health Perspect 117:468–474 (2009)] describes the relationship between children’s blood lead and PbD. Conclusion Most houses with children have PbD levels that comply with federal standards but may put children at risk. Factors associated with PbD in our population-based models are primarily the same as factors identified in smaller at-risk cohorts. PbD on floors and windowsills should be kept as low as possible to protect children.

Community Policies and Programs to Prevent Obesity and Child Adiposity

INTRODUCTIONnEvidence regarding impact of community policies and programs (CPPs) to prevent child obesity is limited, and which combinations of strategies and components are most important is not understood. The Healthy Communities Study was an observational study to assess relationships of characteristics and intensity of CPPs with adiposity, diet, and physical activity in children, taking advantage of variation across the U.S. in community actions to prevent child obesity. The study examined the association of CPPs to prevent child obesity with measured BMI and waist circumference, hypothesizing that communities with more-comprehensive CPPs would have children with lower adiposity.nnnMETHODSnThe study included 130 communities selected by probability-based sampling or because of known CPPs targeting child obesity. Data were collected at home visits on 5,138 children during 2013-2015. CPPs were scored for multiple attributes to create a CPP intensity score. A CPP target behavior score reflected the number of distinct target behaviors addressed. Scores were standardized with the smallest observed score across communities being 0 and the largest 1. Multilevel regression analysis in 2016 adjusted for community, household, and individual characteristics.nnnRESULTSnHigher CPP target behavior score was significantly associated with lower BMI and waist circumference in a dose-response relationship, with magnitude for the past 3 years of CPPs of 0.843 (p=0.013) for BMI and 1.783 cm (p=0.020) for waist circumference.nnnCONCLUSIONSnThis study provides plausible evidence that comprehensive CPPs targeting a greater number of distinct physical activity and nutrition behaviors were associated with lower child adiposity.

Associations of community programs and policies with children's dietary intakes: the Healthy Communities Study: Community programs/policies and child nutrition

The impact of community‐based obesity prevention efforts on child nutrition has not been adequately studied.

Association between community characteristics and implementation of community programmes and policies addressing childhood obesity: the Healthy Communities Study: Community characteristics and programmes

Little is known about whether characteristics of communities are associated with differential implementation of community programmes and policies to promote physical activity and healthy eating. This study examines associations between community characteristics (e.g. region and race/ethnicity) and the intensity of community programmes and policies implemented to prevent childhood obesity. It explores whether community characteristics moderate the intensity of community efforts to prevent childhood obesity.

The longitudinal relationship between community programmes and policies to prevent childhood obesity and BMI in children: the Healthy Communities Study: How community programs & policies affect child BMI

Although a national epidemic of childhood obesity is apparent, how community‐based programmes and policies (CPPs) affect this outcome is not well understood.

Community characteristics modify the relationship between obesity prevention efforts and dietary intake in children: the Healthy Communities Study: Community characteristics influence CPPs and diet

The influence of community characteristics on the effectiveness of childhood obesity prevention efforts is not well understood.

Objectives of community policies and programs associated with more healthful dietary intakes among children: findings from the Healthy Communities Study: Community program objectives and children's diet

Rational planning of community policies and programs (CPPs) to prevent obesity requires an understanding of CPP objectives associated with dietary behaviours.

Associations between community programmes and policies and children's physical activity: the Healthy Communities Study: Community programmes and child physical activity

Community initiatives to promote physical activity in children are common, but evidence supporting their effectiveness is limited.