Research Reports

Dr. Ira Tager and colleagues at the University of California at Berkeley (UCB), and Dr. Patrick Kinney and colleagues at the School of Public Health, Columbia University objectives were to develop new methods for estimating an individual's past exposure to ozone.

Dr. Ultman and his colleagues at Pennsylvania State University redesigned their first-generation analyzer that measures the dose of inhaled ozone to reduce electronic noise (interference) and improve the signal's stability. To do so, they adjusted each parameter that influenced the analyzer's performance: the flow of the air sample into the instrument, the pressure in the chamber where the air sample and the reactant gas mixed, the relative amounts of the reactant gas and air sample, and electronic variables (frequency and voltage).

Dr. John Balmes and colleagues of the University of California, San Francisco, and Dr. Mark Frampton and associates of the University of Rochester characterized ozone-induced responses in two different study populations: normal and asthmatic men and women in the Balmes study (Part I), and male and female nonsmokers and smokers in the Frampton study (Part II). The investigators addressed three issues: (1) Is an individual's reactivity to inhaled methacholine related to changes in lung function after exposure to ozone? (2) What is the relation between ozone-induced airway inflammation and changes in lung function? and (3) Do the changes in lung function and markers of inflammation in response to ozone exposure differ between normal people and people with asthma?

Nitrogen dioxide is a ubiquitous air pollutant resulting from the combustion of fossil fuels. Indoor levels of nitrogen dioxide are often higher than outdoor concentrations, especially in homes where there are unvented heating and cooking appliances that utilize natural gas, kerosene, coal, or wood. Drs. John Spengler, Jonathan Samet, and their colleagues determined the impact of housing characteristics and the type and use of cooking ranges on nitrogen dioxide levels in infants' bedrooms in Albuquerque.

Dr. Susan Bagley and colleagues at Michigan Technological University conducted a laboratory study to characterize the physical and chemical composition, and the mutagenicity of emissions from a heavy-duty 1988 diesel engine equipped with a ceramic particle trap. This engine was operated with low-sulfur fuel at a constant speed under two different load conditions. They also studied the effects of an oxidation catalytic converter on emissions from a heavy-duty 1991 diesel engine using a low-sulfur fuel.

Dr. Weiss and his colleagues at the University of Rochester School of Medicine and Dentistry examined the effects of prenatal and early postnatal inhalation of methanol on selected measures of neurobehavior in rats. The investigators conducted a controlled series of experiments in which they exposed pregnant rats and their newborn offspring to 4,500 parts per million (ppm) methanol by inhalation, and then submitted them to tests of behavioral function.

Dr. Randerath's study was part of a large cancer bioassay conducted by Dr. Joe Mauderly and colleagues of the Inhalation Toxicology Research Institute (ITRI). The investigators exposed F344/N rats by inhalation to clean (filtered) air or to one of two concentrations of either diesel exhaust or carbon (2.5 or 6.5 mg of particles/m³ of test atmosphere). Both Dr. Randerath and Dr. Mauderly measured DNA adducts in lung tissue samples from rats exposed at ITRI for different periods of time to the test atmospheres. Dr.