Carl Hayes

Effects of single- and multiday ozone exposures on respiratory function in active normal children

Ventilatory function was measured twice daily on 46 healthy children aged 8-14 years on at least 7 days for each child during a 4-week period at a northwestern New Jersey residential summer camp in 1988. The highest 1-hr O3 concentration was 150 ppb, while the highest 12-hr H+ concentration (as H2SO4) was 18.6 micrograms/m3. The highest temperature-humidity index was 81 degrees F. The regressions of FVC, FEV1, FEF25-75, and PEFR on O3 in the hour preceding the afternoon function measurements yielded slopes essentially the same as those measured on other children at the same camp in 1984. Regressions of the changes in function between the late morning and late afternoon function measurements on average O3 concentration between them produced significant, but somewhat smaller effects, while regressions of morning function on O3 during the previous day indicated small but still significant effects. There were no significant correlations with other measured environmental variables including H+. Based on the results of this study and similar previous studies, we conclude that O3 exposures in ambient air produce greater lung function deficits in active young people in natural settings then does pure O3 in controlled chamber exposure studies because of: (1) longer exposures; (2) potentiation by other factors in the ambient exposures; (3) the persistence of effects from prior days exposures; and (4) the persistence of a transient response associated with the daily peak of exposure. It follows that projections of likely effects in the real world from controlled chamber exposure studies should either have a large margin of safety, or the judgment of the extent of effects likely to occur among populations should be based directly on the effects observed in field studies.

Chronic respiratory disease. In military inductees and parents of schoolchildren.

Several surveys, relating air pollution exposure to the prevalence of chronic respiratory disease, have recently been conducted by the Community Health and Environmental Surveillance program of the Environmental Protection Agency. The effects of sulfur oxides were studied in the Salt Lake Basin, Rocky Mountain smelter communities, New York City, and Chicago. In all four areas, chronic bronchitis prevalence was higher in polluted neighborhoods than in clean ones. In large urban areas, the effect of air pollution was comparable to the effect of moderate cigarette smoking. In all four areas, the effects of air pollution and of cigarette smoking were roughly additive. In Chattanooga, Tenn, no significant correlation was found between chronic bronchitis prevalence and exposure to moderate urban levels of nitrogen oxides.

Trends in the geographic inequality of cardiovascular disease mortality in the United States, 1962-1982

Substantial geographic variation of cardiovascular disease (CVD) mortality within the U.S. has been recognized for decades. Analyses reported here address the question of whether relative geographic inequality has increased or decreased during the period of rapidly declining CVD mortality 1962-1982. Trends in geographic inequality, as measured by the weighted coefficient of variation of State Economic Area rates, are analyzed for whites and blacks by sex for 10-year age groups 35-44 to 85 and over. The average annual percent change in the coefficient of variation for each demographic group is presented for all cause mortality, all CVD, stroke and ischemic heart disease. In general, geographic inequalities declined in total mortality for all except the youngest age group. This is consistent with reports of a strong convergence of age-adjusted cancer mortality in U.S. counties. By contrast, increasing geographic inequality dominates in the CVD categories, especially for whites in heart disease and stroke. At younger ages, increases in the coefficient of variation for all race-sex groups exceeded 1% per year in stroke and 2% per year in heart disease. These results suggest that factors influencing the percent decline of CVD mortality are not reaching communities of the U.S. equally. Since increases in relative inequality are strongest in the younger age groups, the pattern of inequality may be accentuated as these cohorts move into ages of higher mortality.

Epidemiological study of respiratory responses to indoor/outdoor air quality

Abstract Exposures to outdoor-type pollutants have been linked to indoor sources and exposures to indoor-specific pollutants also occur. The recognition of indoor air quality as a major component of total human exposure to air pollutants has raised serious questions about the adequacy of exposure assessment in previous air pollution health effects studies. Not only do outdoor pollutants penetrate indoors in the workplace or school and in the home, but these locations may also contain sources of air pollutants (i.e., nitrogen dioxide, suspended particulate matter, and formaldehyde). Thus, a study has been designed to evaluate respiratory responses to pollutant exposures from indoor and outdoor sources. Evaluation of interactions of measured pollutants and their effects on health is designed to be a major component of this study.

The design considerations for ozone and acid aerosol exposure and health investigations: The fairview lake summer camp — Photochemical smog case study

Abstract The health effects associated with ozone and acidic particulate sulfate exposures to active children have been and are being addressed in field epidemiological studies at summar camps in rural areas of the Northeastern U.S. The rationale and study design for studies, which have been conducted in Pennsylvania and New Jersey, are developed and reviewed. As background, results are summarized for human clinical and epidemiological studies and animal studies. These provided the basis for selection of health outcomes measured results from chemical characterization and transport studies are reviewed to define the criteria used for selection of a site which is effected by high ozone and acid species during photochemical smog episodes. The integration of the study design is discussed in detail by reviewing it application to the 1984 — Fairview Lake Camp Study (July 8 to August 4). The features of the camp study are reviewed, including the study population, pulmonary function procedures and analyses, air pollution monitoring instrumentation, and the site characteristics. The pollution exposure data are presented, for ozone and acidic sulfates and examined for the range and distribution concentration. Further information is provided on the intensity and duration of episodes encountered over the course of the study. Episodes occurred which had ozone and acid sulfates, ozone alone, and acid sulfates alone.

U.S. Environmental Protection Agency's Ozone Epidemiology Research Program: a strategy for assessing the effects of ambient ozone exposure upon morbidity in exposed populations.

The Clean Air Act Amendments of 1990 mandate a future reduction of ambient ozone levels in many areas of the country, the cost of which will be great. In order to assess the current public health burden of ambient ozone exposure and to provide information for assessment of potential health benefits of improved air quality, the Health Effects Research Laboratory of the U.S. EPA has undertaken an Ozone Epidemiology Research Program. The research strategy which will guide this scientific program is described in this paper. Criteria for selection of important research questions as well as issues which cut across all questions and study designs are discussed. In particular, this program emphasizes the study of effects which reflect morbidity in the population. The three questions identified as being of most immediate importance involve the relationship of short-term ambient ozone exposure to acute respiratory illness, the relationship of recurrent exposure to chronic respiratory disease, and the relationship of recurrent exposure to development of acute respiratory illness. Specific research approaches and initial projects to address these three questions are described.

Confidentiality and freedom of information for epidemiological data in governmental research

Abstract The issues of confidentiality and freedom of information are discussed for studies involving health surveillance around point sources of pollution. The problems discussed are related to protecting data after a study has been initiated. Research studies describing the impact of confidentiality on response rates are discussed. The U.S. Environmental Protection Agencys current and proposed procedures for handling and releasing these data are presented. These can be used by other agencies in defining their security procedures