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)

Nitrogen Dioxide and Respiratory Infection: Pilot Investigations

Research Report 28

Jonathan M Samet

John Spengler

1989

Topics:

Nitrogen Oxides

This report describes two pilot investigations for a longitudinal study of infants designed to determine if NO₂ exposure from cooking stoves increases the incidence or severity of respiratory infections during the first 18 months of life. In the first study, Drs. Samet and Spengler selected 147 households with electric or gas stoves and infants for home indoor monitoring of NO₂ concentrations; the infants\' mothers completed a daily calendar-diary on respiratory symptoms and provided illness information every 2 weeks.

Early Markers of Lung Injury

Research Report 29

John N Evans

David R Hemenway

Jason Kelley

1989

Topics:

Nitrogen Oxides

This report describes a study by Dr. Evans and colleagues to develop an early marker of lung injury that changes in response to exposure to NO₂, which is an important component of mobile source emissions. Rats were exposed to NO₂ in concentrations ranging from 0.5 to 30 ppm for 6 hours per day for periods ranging from 2 days to 4 weeks. Urine and bronchoalveloar lavage samples were collected and analyzed for the presence of the lung injury markers hydroxylysin, angiotensin-converting enzyme, and desmosine.

Cardiovascular Effects of Chronic Carbon Monoxide and High-Altitude Exposure

Research Report 27

James J McGrath

1989

Topics:

Carbon Monoxide

This report describes a study by Dr. McGrath to investigate the effect of chronic exposure of rats to CO at high altitude. Male rats were exposed for 6 weeks to CO ranging from 0 to 500 ppm at simulated altitudes ranging from 3,300 to 18,000 feet. The following weekly measurements were taken throughout the exposure period: weight, hematocrit, hemoglobin, and carboxyhemoglobin concentrations. Arterial pH, partial pressure of CO in the blood (PCO₂) and PO₂ were measured, as were blood pressure and ECG.

Investigation of a Potential Cotumorigenic Effect of the Dioxides of Nitrogen and Sulfur, and of Diesel-Engine Exhaust, on the Respiratory Tract of Syrian Golden Hamsters

Research Report 26

Uwe Heinrich

Ulrich Mohr

Rainer Fuhst

Carsten Brockmeyer

1989

Topics:

Diesel Exhaust

Nitrogen Oxides

This report describes a study by Dr. Heinrich and colleagues to investigate the effects of exposure to NO₂ and SO₂ or diesel engine exhaust on tumor formation in hamsters. Hamsters were exposed for 6, 10.5, 15, or 18 months to whole diesel exhaust, diesel exhaust without particles, or a mixture of NO₂ and SO₂. Additional groups of animals exposed to each test atmosphere were also injected with 3 or 6 mg of diethylnitrosamine/kg body weight to evaluate any enhancing effect of diethylnitrosamine on exposure-related changes.

Altered Susceptibility to Viral Respiratory Infection During Short-Term Exposure to Nitrogen Dioxide

Research Report 24

Richard M Rose

Paula Pinkston

William A Skornik

1989

Topics:

Nitrogen Oxides

This report examined the effect of nitrogen dioxide exposure on the sensitivity of the lower respiratory tract to viral infection and reinfection. Dr. Rose and colleagues exposed mice to concentrations of nitrogen dioxide ranging from 1-10 ppm or to air prior to and after inoculation with varying doses of murine cytomegalovirus. A subset of mice was reinfected 30 days later. Infection status, macrophage phagocytic uptake, lymphocyte function, and virus-specific antibody levels were measured, and the results were compared by exposure condition.

Detection of Paracrine Factors in Oxidant Lung Injury

Research Report 22

Keith A Tanswell

1989

Topics:

Ozone & Oxidants

This report addressed the hypothesis that hypertrophy of the lung after oxidant injury with ozone or oxygen is due to local generation of lung-specific growth factors. Dr. Tanswell exposed rats to either 85% oxygen, 1 ppm ozone, or air for up to two weeks while samples of plasma, lung washings, and lung tissue were periodically collected. These samples were tested for their effect on the DNA synthesis of purified populations of three major lung cell types (pneumocyte, fibroblast, and endothelial cell) in culture.

Responses of Susceptible Subpopulations to Nitrogen Dioxide

Research Report 23

Paul E Morrow

Mark J Utell

1989

Topics:

Nitrogen Oxides

This report investigated changes in pulmonary function, as well as the occurrence of symptoms, in potentially susceptible human subpopulations exposed to nitrogen dioxide. Drs. Morrow and Utell exposed healthy individuals and individuals with asthma, chronic obstructive pulmonary disease, and acute respiratory infection to air or 0.3 ppm nitrogen dioxide. The exposure period (four hours per day for five consecutive days) included defined periods of moderate exercise and pulmonary function measurements including spirometry, airway conductance, airway reactivity, and symptoms.

Maximal Aerobic Capacity at Several Ambient Concentrations of Carbon Monoxide at Several Altitudes

Research Report 21

Steven M Horvath

James W Agnew

Jeames A Wagner

John F Bedi

1988

Topics:

Carbon Monoxide

This report examined the interactive effects induced by exposure to altitude and carbon monoxide. Dr. Horvath and colleagues exposed 23 healthy young human volunteers living at sea level to concentrations of 0, 50, 100, or 150 ppm carbon monoxide in a hyperbaric chamber simulating altitudes of 55, 1,524, 2,134, or 3, 048 meters above sea level. Maximal aerobic capacity tests were performed under each exposure condition while respiratory and cardiac variables and blood levels of carboxyhemoglobin, hemoglobin, and lactate were monitored.

Modulation of Pulmonary Defense Mechanisms Against Viral and Bacterial Infections by Acute Exposures to Nitrogen Dioxide

Research Report 20

George J Jakab

1988

Topics:

Nitrogen Oxides

This report investigated the influence of acute exposure to nitrogen dioxide on susceptibility to and severity of viral and bacterial infection in mice. Dr. Jakab exposed normal and immunosuppressed mice to concentrations of nitrogen dioxide ranging from 1 to 30 ppm before or after bacterial or viral challenge and measured host resistance to infection by physiologic parameters.

Factors Affecting Possible Carcinogenicity of Inhaled Nitropyrene Aerosols

Research Report 19

Ronald K Wolff

Edward Barr

James A Bond

Arthur F Eidson

William C Griffith

Fletcher F Hahn

Jack R Harkema

Rogene F Henderson

Charles E Mitchell

Simon J Rothenberg

George M Shopp

James D Sun

1988

Topics:

Diesel Exhaust

This report assessed in rats the carcinogenicity of inhaled 1-nitropyrene, a compound frequently adsorbed to diesel particulate matter, and whether this effect is modified when 1-nitropyrene is associated with particles or irritant gases. Dr. Wolff and colleagues exposed rats to atmospheres containing 14C radiolabeled 1-nitropyrene alone or in combination with gallium oxide, sulfur dioxide, or both. After exposure, tissue samples were analyzed for radiolabel content to determine the tissue distribution of 1-nitropyrene and its metabolites.