Research Reports

HEI’s mission is to provide credible science to support environmental regulations and other policy decisions. The results of each HEI-funded project undergo peer-review by outside scientists and the Health Review Committee. The HEI Research Reports contain the Investigator’s Report and the Review Committee’s evaluation of the study, summarized in a Commentary or short Critique.

ISSN 1041-5505 (print) ISSN 2688-6855 (online)

The Effects of Exercise on Dose and Dose Distribution of Inhaled Automotive Pollutants

Research Report 45

Michael T Kleinman

William J Mautz

1991

Topics:

The human health effects that result from breathing air pollutants depend on the amount of pollutant inhaled from the air (exposure dose) and the amount of inhaled material that stays in the respiratory tract (retained dose). Because the retained dose of a pollutant may damage the respiratory tract and cause disease, it is a key factor for determining appropriate government regulations for air pollutants. Drs.

Leukocyte-Mediated Epithelial Injury in Ozone-Exposed Rat Lung

Research Report 44

Kenneth Donaldson

Geraldine M Brown

David M Brown

Joan Slight

William M Maclaren

John MG Davis

1991

Topics:

Ozone & Oxidants

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. When inhaled, ozone can cause cough, shortness of breath, and transient changes in breathing patterns; however the health significance of these effects is unknown. Drs. Kenneth Donaldson and coworkers at the Institute of Occupational Medicine examined whether exposure to ozone activates white blood cells to release substances that can damage lung tissue.

Effects of Methanol Vapor on Human Neurobehavioral Measures

Research Report 42

Mary R Cook

Fred J Bergman

Harvey D Cohen

Mary M Gerkovich

Charles Graham

Roger K Harris

Linda G Siemann

1991

Topics:

Air Pollution

Air Toxics

Emerging Technologies

Fuels & Fuel Additives

In this pilot study, Dr. Mary Cook and colleagues at the Midwest Research Institute explored how exposure to methanol vapor might affect the human nervous system. Methanol could be used as an alternative fuel, but it may lead to increased levels of methanol and formaldehyde in the atmosphere. The investigators exposed 12 young male volunteers to either filtered air or methanol vapor and assessed their response using 20 commonly used tests of sensory, behavioral, and reasoning performance before, during, and after each exposure.

Mechanisms of Nitrogen Dioxide Toxicity in Humans

Research Report 43

Mark J Utell

Mark W Frampton

Norbert J Roberts Jr

Jacob N Finkelstein

Christopher Cox

Paul E Morrow

1991

Topics:

Nitrogen Oxides

Nitrogen dioxide is an ubiquitous air pollutant that can react with and damages lung cells when inhaled at high levels. Although outdoor and indoor levels of nitrogen dioxide are usually below the annual standard of 0.053 ppm, peaks can occur that reach up to 10 times this standard. Dr. Mark Utell and coworkers at the University of Rochester examined the human health impacts of higher (peak) levels of nitrogen dioxide that exceed the annual standard. The investigators exposed healthy, nonasthmatic, human volunteers to either nitrogen dioxide or filtered air for three hours.

Effects of 4 Percent and 6 Percent Carboxyhemoglobin on Arrhythmia Production in Patients with Coronary Artery Disease

Research Report 41

David S Sheps

Margaret C Herbst

Alan L Hinderliter

Kirkwood F Adams

Lars G Ekelund

John J O'Neil

George M Goldstein

Philip A Bromberg

Martha Ballanger

Sonia M Davis

Gary Koch

1991

Topics:

Carbon Monoxide

Dr. Sheps and colleagues assessed the effect of exposure to carbon monoxide (CO) on ventricular arrhythmias in 41 nonsmoking human volunteers with coronary artery disease. On 3 consecutive days, volunteers were exposed in random order to air, 100 ppm CO (target 4% carboxyhemoglobin), and 200 ppm CO (target 6% carboxyhemoglobin), followed by a bicycle exercise test. Radionuclide cardiac ventriculography and ambulatory electrocardiogram were performed at rest and during exercise.

Retention Modeling of Diesel Exhaust Particles in Rats and Humans

Research Report 40

CP Yu

KJ Yoon

1991

Topics:

Diesel Exhaust

Biological Methods

This report describes a study by Drs. Yu and Yoon to mathematically predict the lung burden in rats and humans of diesel exhaust particles (DEP) from automobile emissions. Building on a previously constructed model describing DEP deposition, the present work focused on clearance and retention of DEPs deposited in the lung. The transport rates of each component of DEPs were derived using experimental data and mathematical approximations. The complete model was first developed for rats and then extrapolated to humans of different age groups.

Noninvasive Determination of Respiratory Ozone Absorption: Development of a Fast-Responding Ozone Analyzer

Research Report 39

James S Ultman

Abdellaziz Ben-Jebria

1991

Topics:

Ozone & Oxidants

Biological Methods

This report describes a study by Drs. Ultman and Ben-Jebria to develop a chemiluminescent ozone analyzer and constructed an ozone bolus generator with the goal of using bolus concentration-response methods to noninvasively measure the longitudinal distribution of ozone absorption in human lungs. The analyzer was based on the chemiluminescent reaction between 2-methyl-2-butene and ozone. Validation of the system was performed in excised pig and sheep tracheas, and the resulting absorption coefficient was computed.

Synergistic Effects of Air Pollutants: Ozone Plus a Respirable Aerosol

Research Report 38

Jerold A Last

1991

Topics:

Multipollutant Mixtures

Ozone & Oxidants

This report describes a study by Dr. Last to investigate possible synergistic effects of multiple air pollutants on pulmonary measures in rats. Rats were exposed for 1-9 days to mixtures of O₃ or NO₂ and aerosols of sulfuric acid, ammonium sulfate, or sodium chloride, and to each pollutant individually. Responses were evaluated by various biochemical and morphometric analyses of lung tissue and lavage fluid. An additional preliminary experiment treated exposed rats in vivo with various free-radical scavengers to elucidate possible protective properties.

Carbon Monoxide and Lethal Arrhythmias

Research Report 36

Jay P Farber

Peter J Schwartz

Emilio Vanoli

Marco Stramba-Badiale

Gaetano M De Ferrari

1990

Topics:

Carbon Monoxide

This report describes a study by Dr. Farber and colleagues to investigate the effect of carbon monoxide (CO) exposure on cardiac parameters in dogs. They tested dogs that developed ventricular fibrillation during a test of exercise and acute myocardial ischemia (i.e. that were susceptible) and dogs that survived the test without fatal arrhythmias (i.e that were resistant). Susceptible and resistant dogs were exposed to a concentration of CO sufficient to raise carboxyhemoglobin levels to 5 – 15%.

Oxidant Effects on Rat and Human Lung Proteinase Inhibitors

Research Report 37

David A Johnson

R Steve Winters

Kwan R Lee

Craig E Smith

1990

Topics:

Diesel Exhaust

Nitrogen Oxides

This report describes a study by Dr. Johnson and colleagues to test the hypothesis that inhaled oxidants can cause lung damage by inactivating the proteinase inhibitors that normally protect the lung from proteolysis. In the first set of experiments, the functional activity of rat alpha-1-proteinase inhibitor (á1-PI) was measured in rat lung lavage fluid from rats exposed acutely or chronically to varying concentrations of NO₂, diesel exhaust, O₃, and O₃ in conjunction with CO₂.