Prevalence of Lead Hazards and Soil Arsenic in U.S. Housing.

The American Healthy Homes Survey, June 2005-March 2006, measured levels of lead and arsenic in homes nationwide. Based on a three-stage cluster sample of 1,131 housing units, key statistically weighted estimates of the prevalence of lead-based paint (LBP) and LBP hazards associated with paint, dust, and soil, and arsenic in dust and soil, were as follows: 37.1 million homes (35%) had some LBP; 23.2 million (22%) had one or more LBP hazards; 93% of the homes with LBP were built before 1978. The highest prevalence of LBP and LBP hazards was in the Northeast and Midwest. Over three million homes with children under six years of age had LBP hazards, including 1.1 million low-income households (< $30,000/yr.). Less than 5% of homes had detectable levels of arsenic in dust (≥ 5 µg/ft2). Arsenic in soil (for homes with yard soil) averaged 6.6 parts per million (ppm). Many homes had soil arsenic levels of 20 ppm or greater, including 16% of homes with wooden structures in the yard and 8% of homes without such structures.

Lead, allergen, and pesticide levels in licensed child care centers in the United States.

The First National Environmental Health Survey of Child Care Centers was conducted to provide information about lead, allergen, and pesticide levels in licensed U.S. child care centers. Lead levels were measured in settled dust, paint, and play area soil; indoor allergen levels were measured in settled dust; and pesticide residues were measured on indoor surfaces and in play area soil. Fourteen percent of centers had significant lead hazards, suggesting that an estimated 470,000 children under age six (approximately 10% of all children in licensed centers) attend centers with significant lead hazards. Approximately 5% of centers had levels of allergens associated with asthma and allergic conditions. Three-quarters of centers had pesticides applied (either indoors or outdoors) during the previous year. Although most centers did not appear to present risks from lead and allergens, some centers did have unsafe levels of these contaminants. These conclusions cannot be generalized to unlicensed child care arrangements.

Methodological and Statistical Considerations for the National Children's Study.

The National Children's Study (NCS) statistics and item response theory group was tasked with promoting the quality of study measures and analysis. This paper provides an overview of six measurement and statistical considerations for the NCS: (1) Conceptual and Measurement Model; (2) Reliability; (3) Validity; (4) Measurement Invariance; (5) Interpretability of Scores; and (6) Burden of administration. The guidance was based primarily on recommendations of the International Society of Quality of Life Research.

Comparable measures of cognitive function in human infants and laboratory animals to identify environmental health risks to children.

The importance of including neurodevelopmental end points in environmental studies is clear. A validated measure of cognitive function in human infants that also has a homologous or parallel test in laboratory animal studies will provide a valuable approach for large-scale studies. Such a comparable test will allow researchers to observe the effect of environmental neurotoxicants in animals and relate those findings to humans. In this article, we present the results of a review of post-1990, peer-reviewed literature and current research examining measures of cognitive function that can be applied to both human infants (0-12 months old) and laboratory animals. We begin with a discussion of the definition of cognitive function and important considerations in cross-species research. We then describe identified comparable measures, providing a description of the test in human infants and animal subjects. Available information on test reliability, validity, and population norms, as well as test limitations and constraints, is also presented.

Pesticide measurements from the first national environmental health survey of child care centers using a multi-residue GC/MS analysis method.

The U.S. Department of Housing and Urban Development, in collaboration with the U.S. Consumer Product Safety Commission and the U.S. Environmental Protection Agency, characterized the environments of young children (<6 years) by measuring lead, allergens, and pesticides in a randomly selected nationally representative sample of licensed institutional child care centers. Multi-stage sampling with clustering was used to select 168 child care centers in 30 primary sampling units in the United States. Centers were recruited into the study by telephone interviewers. Samples for pesticides, lead, and allergens were collected at multiple locations in each center by field technicians. Field sampling was conducted from July through October 2001. Wipe samples from indoor surfaces (floors, tabletops, desks) and soil samples were collected at the centers and analyzed using a multi-residue GC/MS analysis method. Based on the questionnaire responses, pyrethroids were the most commonly used pesticides among centers applying pesticides. Among the 63% of centers reporting pesticide applications, the number of pesticides used in each center ranged from 1 to 10 and the frequency of use ranged from 1 to 107 times annually. Numerous organophosphate and pyrethroid pesticides were detected in the indoor floor wipe samples. Chlorpyrifos (0.004-28 ng/cm2), diazinon (0.002-18 ng/cm2), cis-permethrin (0.004-3 ng/cm2), and