Research Reports

Dr James Ultman and colleagues at Pennsylvania State University recruited 32 men and 28 women to examine differences in ozone uptake in the lung. The subjects (all non smokers) first took a series of single breaths of air–ozone mixtures, which allowed the investigators to examine how ozone was distributed in the airways and where the major fraction of ozone was taken up. In a follow-up test, the subjects pedaled a bicycle ergometer to produce conditions of moderate exercise for one hour while breathing clean air, followed by a third test while breathing ozone at 0.25 ppm).

Dr. Beverly Cohen and her colleagues at New York University School of Medicine tested the performance of iron nanofilms to collect and measure sulfuric acid particles of different sizes under a variety of temperature and humidity conditions. The iron nanofilm detector is a thin iron-coated silicon chip. Particles would react with the iron, creating an elevated site or bump on the film surface, which can be visualized using an atomic force microscope.

In Part III of the National Morbidity, Mortality, and Air Pollution Study (NMMAPS), Dr. Daniels and colleagues at Johns Hopkins University and Harvard University evaluated the shape of the relation between PM₁₀ concentrations measured at fixed monitoring sites and daily mortality among residents from all causes (excluding accidental causes), from all cardiovascular and respiratory causes combined, and from causes other than cardiovascular-respiratory disease.

Dr. Laskin and her colleagues at the Environmental and Occupational Health Sciences Institute at Rutgers University tested the hypothesis that oxidants in ambient air, such as hydrogen peroxide, may be transported by fine particulate matter into the lungs and thus contribute to lung tissue injury. The investigators used ammonium sulfate particles because of their prevalence in the ambient air of the eastern United States and their reportedly low toxicity in animals and humans.

Stephen Holgate and his colleagues at the University of Southampton proposed that inflammatory changes in lung fluids and blood from humans exposed to PM were related to the chemical composition of the particles. He obtained samples from two human studies in which participants were exposed to diesel exhaust and concentrated ambient particles (CAPs). At a Swedish laboratory 25 healthy and 12 asthmatic participants were exposed to diesel exhaust or filtered air on separate days. At a US laboratory, 12 healthy participants were exposed to filtered air and 30 different healthy participants were exposed to a range of CAPs concentrations. All participants underwent bronchoscopy to obtain lung tissues and fluids to analyze inflammatory markers, including numbers of specific white blood cells, expression of activation markers, and levels of cytokines in addition to analysis of lung function, lung fluids, and blood.

Dr. Albertini and colleges organized a group of researchers from the United States, Czech Republic, The Netherlands, and the United Kingdom to determine whether biomarkers in the blood and urine of workers exposed to butadiene in occupational settings correlated with their personal exposure. Samples were collected from male workers employed either in a plant that used butadiene and styrene to produce rubber polymer in Prague. They also collected blood and urine from male administrative workers at the plant who had no direct occupational exposure to butadiene and served as control subjects.

Drs Turteltaub and Mani at Lawrence Livermore National Laboratory investigated benzene metabolism in rodents over a large dose range that encompassed concentrations close to those of human ambient exposure. Understanding benzene metabolism at low exposure levels is critical to benzene assessment to determine the shape of the dose-response curve at low concentrations.The investigators administered radioactive benzene to mice and rats and subsequently analyzed bone marrow, liver, urine, and plasma from these animals.