Research Reports

Ozone is a highly reactive gas that is a pervasive air pollutant at ground level. It is a major component of urban smog, forming when emissions from mobile and industrial sources interact with sunlight. The study of the effects of long-term ozone exposure on lung complex carbohydrates, described in this report, was one of eight laboratory studies supported by the NTP/HEI collaborative agreement. In addition to studying lung and nasal structure and function, investigators studied other constituents of lung connective tissue. Dr.

Ozone is a major outdoor air pollutant and short term inhalation can produce temporary chest discomfort, and transient changes in breathing patterns and lung function. Because a large number of people are exposed to levels of ozone sufficient to cause effects on breathing, it is important to understand the short- and long-term consequences of these exposures for human health. Dr.

Dr. Fennell at the Chemical Industry Institute of Toxicology sought to develop new methods for improving the detection of formaldehyde-DNA adducts in exposed cells and tissues. The investigator treated formaldehyde-DNA adducts with sodium bisulfite, a compound that reacts with these adducts and traps them as stable compounds, and then tested different analytical techniques for separating and detecting the adducts. He exposed pure DNA, cell nuclei, and cells in culture to formaldehyde and treated them with sodium bisulfite under a variety of experimental conditions.

Exposure to polycyclic aromatic hydrocarbons (PAHs) and their nitro-substituted derivatives (nitro-PAHs), products of incomplete combustion, is widespread. This is of concern because individual PAHs and PAH-containing mixtures cause tumors in animals and they are suspected to contribute to human cancer. To asses their carcinogenic potential in humans, biomarkers of PAH exposure that measure the internal dose or the effective dose need to be developed. Dr.