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Related Experiment Video

Updated: Jul 27, 2026

Implementation of Portable Emissions Measurement Systems (PEMS) for the Real-driving Emissions (RDE) Regulation in Europe

Implementation of Portable Emissions Measurement Systems (PEMS) for the Real-driving Emissions (RDE) Regulation in Europe

Published on: December 4, 2016

What is new in diesel.

William B Bunn¹, P A Valberg, T J Slavin

¹International Truck and Engine Corporation, 4201 Winfield Rd, Warrenville, IL 60555, USA. William.Bunn@nav-international.com

International Archives of Occupational and Environmental Health

|October 25, 2002

Summary

Recent diesel exhaust (DE) technologies reduce harmful emissions. Current evidence suggests DE is not a concern at ambient exposure levels, and past risk assessments require re-evaluation due to flawed data.

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Nitrogen Compound Characterization in Fuels by Multidimensional Gas Chromatography

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Published on: May 15, 2020

Area of Science:

Environmental Health
Toxicology
Occupational Health

Background:

Diesel exhaust (DE) technologies have evolved, altering emission compositions and reducing key components of health concern.
Modern diesel and compressed natural gas engine emissions are increasingly similar, necessitating regulatory analysis adjustments.
Previous studies on DE toxicity and human exposure have yielded data insufficient for robust risk assessment.

Purpose of the Study:

To review recent changes in diesel exhaust emissions and toxicity studies over the past five years.
To critically evaluate the validity of existing data used for diesel exhaust risk assessment.
To identify knowledge gaps and the need for further research in diesel exhaust exposure and health effects.

Main Methods:

Comprehensive review of scientific literature published within the last five years.
Analysis of animal inhalation studies across various species (hamsters, guinea pigs, mice, rats).
Re-evaluation of occupational epidemiology studies concerning diesel exhaust exposure in different workforces.

Main Results:

New DE technologies have significantly reduced emissions of harmful components.
Animal studies indicate DE is not a lung carcinogen at ambient exposure levels; tumors in rats occurred only under lung overload conditions, similar to inert dusts.
Re-analyses of occupational studies reveal serious flaws, including lack of dose-response relationships and confounding factors, weakening previous risk characterizations.

Conclusions:

Existing animal data suggest DE is not a significant health concern at typical ambient exposure levels.
Epidemiological data supporting DE carcinogenicity are compromised by methodological shortcomings and lack of clear dose-response.
Further research with improved exposure measurements is essential for accurate diesel exhaust risk assessment.