Diesel Exhaust Particles in the Work Environment and their Analysis

Abstract

Diesel engines are widely used in industries, for example transportation, mining, and construction, because they efficiently produce high power. In diesel exhaust particles (DEP), the number of ultrafine particles, less than around 100 nm, is dominant in contrast to mass size distribution. Carcinogenic PAHs may be adsorbed on DEP at high concentrations. As occupational exposure usually occurs near emission sources, workers are likely to be exposed to high concentration DEP. The exhaust emissions of diesel engines have become lower by modification of the engines and fuels, and introduction of filters and catalysts, thus it has become more difficult to monitor mass and chemical components in DEP. New technology and instruments are being introduced to characterize DEP especially chemically. Recently, quick analytical methods without extraction, and continuous or semi-continuous methods have been introduced. This article will review 1) Elemental Carbon (EC) monitors, 2) analytical methods of individual PAH without solvent extraction, and 3) continuous PAH monitor, because EC and PAH are typical constituents for DEP.

Exposure to diesel exhaust fumes in the context of exposure to ultrafine particles

“…Ultrafine particles are emitted directly from the engine or may arise from condensation of the exhaust gas. In the environment they combine very fast into larger groups and aggregate, and thus their lifetime as independent particles is short [3,4]. Typical diesel particles are usually agglomerates consisting of approx.…”

Impact of short-term preconceptional exposure to particulate air pollution on treatment outcome in couples undergoing in vitro fertilization and embryo transfer (IVF/ET)

“…The total mass of DEP is composed of 40% inorganic carbonaceous substance (elemental carbon, EC), 30% organic carbonaceous substances derived from unburned fuel and oil, and 30% sulfate, water, ash and others. Size distribution of DEP ranges from coarse particles (with aerodynamic diameter 2.5-10 µm) to ultrafine particles (with aerodynamic diameter <0.1 µm), which are dominant in the number-size distribution in contrast to the larger particles that dominate the mass-size distribution [8].…”

Assessment of Workplace Diesel Exhaust Exposure and Health Effects

“…The PM size generally represents different sources and display different physical and chemical properties, but the properties associated with toxicity are incompletely understood. The four main characteristics of DPM include a high proportion of elemental carbon; a large surface area associated with carbonaceous particles in the 0.2μm size range; polycyclic organic compounds adsorbed to particles; and 50-90% of the number of particles are ultrafine (<1um), with a mode of 20nm [12]. Particles are of particular concern as smaller particles have large surface area to which toxic components can be adsorbed.…”