William C. Nelson

The Effect of Sulfur Dioxide and Suspended Sulfates on Acute Respiratory Disease

Studies carried out in four distinct geographic areas of the United States involving 20,472 children and adults clearly linked excessive, acute respiratory disease with communities heavily polluted with sulfur dioxide and suspended sulfates. Pollution exposure of three years or longer was an important component in increased risk for acute respiratory disease. Laryngo- tracheobronchitis was the major condition productive of excess, acute, lower-respiratory disease in children in heavily polluted communities in the Salt Lake Basin and Rocky Mountain communities. The effect of pollution on excess, acute respiratory disease was found to be independent of socioeconomic status and cigarette smoking.

Particulate and Nicotine Sampling in Public Facilities and Offices

The purpose of this study was to characterize and measure indoor air quality in public facilities and office buildings. The pollutants of interest were particulate matter smaller than 2.5 microns in diameter, PM-2.5, and environmental tobacco smoke (ETS). Integrated PM-2.5 samples were taken on Teflon membrane filters using Harvard Aerosol Impactors as a pre-size selector. Filters were analyzed by gravimetric analysis. Nicotine, which was used as a marker for ETS, was collected on sodium-bisulfate-impregnanted, glass-fiber filters and was analyzed by gas chromatography. Twenty-one structures were monitored in Metropolitan Boston. Measured particle concentrations ranged from 6.0 micrograms/m3 to about 550 micrograms/m3. Nicotine concentrations were as high as 26 micrograms/m3 in a designated smoking room. Real-time measurements were also taken using two types of nephelometers; a Handheld Aerosol Monitor (HAM) and a Miniature Real-Time Aerosol Monitor (MINIRAM). Short-term field measurements with these instruments correlated better with the integrated PM-2.5 concentrations in smoking locations than with concentrations in non-smoking areas.

Temporal Variation of Carboxyhemoglobin Concentrations

Carboxyhemoglobin concentrations ([COHb]) were measured in 15 subjects by analysis of alveolar air samples collected at two-hour intervals during waking hours on seven consecutive days. Overall mean values were 3.80% COHb for five cigarette smokers and 1.64% COHb for ten nonsmokers. Analysis of the results indicates that long-term average [COHb] can be estimated with fair reliability from two or more instantaneous samples for each subject. This technique may be useful in estimating chronic carbon monoxide (CO) exposures for epidemiologic studies.

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