Steven M. Bortnick

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CONTEXT Residential exposures are recognized risk factors for asthma, but the relative contribution of specific indoor allergens and their overall contribution to asthma among older children and adolescents in the United States are unknown. OBJECTIVE To estimate the relative contributions, population-attributable risks, and costs of residential risk(More)
Considerable attention has been given to the relationship between levels of fine particulate matter (particulate matter < or = 2.5 microm in aerodynamic diameter; PM(2.5) in the atmosphere and health effects in human populations. Since the U.S. Environmental Protection Agency began widespread monitoring of PM(2.5) levels in 1999, the epidemiologic community(More)
A Bayesian hierarchical regime switching model describing the spatial–temporal behavior of ozone (O3) within a domain covering Lake Michigan during spring–summer 1999 is developed. The model incorporates linkages between ozone and meteorology. It is specifically formulated to identify meteorological regimes conducive of high ozone levels and allow ozone(More)
A video imaging system and the associated quantification methods have been developed for measurement of the transfer of a fluorescent tracer from surfaces to hands. The highly fluorescent compound riboflavin (vitamin B2), which is also water soluble and non-toxic, was chosen as the tracer compound to simulate the transfer from surfaces to hands of pesticide(More)
A model for children's blood lead concentrations as a function of environmental lead exposures was developed by combining two nationally representative sources of data that characterize the marginal distributions of blood lead and environmental lead with a third regional dataset that contains joint measures of blood lead and environmental lead. The(More)
As stated in 40 CFR 58, Appendix G (2000), statistical linear regression models can be applied to relate PM2.5 continuous monitoring (CM) measurements with federal reference method (FRM) measurements, collocated or otherwise, for the purpose of reporting the air quality index (AQI). The CM measurements can then be transformed via the model to remove any(More)
The problem of providing lower confidence bounds for the mean improvements of p ≥ 2 test treatments over a control treatment is considered. The expected average and expected maximum allowances are two criteria for comparing different systems of confidence intervals or bounds. In this paper, lower bounds are derived for the expected average allowance and the(More)
The U.S. Environmental Protection Agency (EPA) is in the process of designing a national network to monitor hazardous air pollutants (HAPs), also known as air toxics. The purposes of the expanded monitoring are to (1) characterize ambient concentrations in representative areas; (2) provide data to support and evaluate dispersion and receptor models; and (3)(More)
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