Biological effects of diesel exhaust inhalation. III cardiovascular function

Abstract

Objective

Inhalation of diesel exhaust (DE) has been shown to be an occupational hazard in the transportation, mining, and gas and oil industries. DE also contributes to air pollution, and therefore, is a health hazard to the general public. Because of its effects on human health, changes have been made to diesel engines to reduce both the amounts of particulate matter and volatile fumes they generate. The goal of the current study was to examine the effects of inhalation of diesel exhaust.

Materials and Methods

The study presented here specifically examines the effects of exposure to 0.2 and 1.0 mg/m³ DE or filtered air (6h/d for 4 d) on measures of peripheral and cardio-vascular function, and biomarkers of heart and kidney dysfunction in male rats. A Tier 2 engine used in oil and gas fracking operations was used to generate the diesel exhaust.

Results

Exposure to 0.2 mg/m³ DE resulted in an increase in blood pressure 1d following the last exposure, and increases in dobutamine-induced cardiac output and stroke volume 1 and 27d after exposure. Changes in peripheral vascular responses to norepinephrine and acetylcholine were minimal as were changes in transcript expression in the heart and kidney. Exposure to 1.0 mg/m³ DE did not result in major changes in blood pressure, measures of cardiac function, peripheral vascular function or transcript expression.

Discussion and Conclusions

Based on the results of this study, we suggest that exposure to DE generated by a Tier 2 compliant diesel engine generates acute effects on biomarkers indicative of cardiovascular dysfunction. Recovery occurs quickly with most measures of vascular/cardiovascular function returning to baseline levels by 7d following exposure.

Keywords:

• Blood pressure
• cardiac function
• vascular function
• particulate
• diesel exhaust

Disclosure statement

The authors declare that they have no conflicts of interest in relation to this publication.

Disclaimer

The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention. Mention of brand name does not constitute product endorsement.

Data availability statement

Once published, data presented in tis manuscript will be available through the National Institute for Occupational Safety and Health.

Additional information

Funding

This work was funded by a National Occupational Research Agenda Award from the National Institute for Occupational Safety and Health awarded to Jeffrey Fedan 6927ZLDC.