Particulate matter beyond mass: recent health evidence on the role of fractions, chemical constituents and sources of emission

Abstract

Particulate matter (PM) is regulated in various parts of the world based on specific size cut offs, often expressed as 10 or 2.5 µm mass median aerodynamic diameter. This pollutant is deemed one of the most dangerous to health and moreover, problems persist with high ambient concentrations. Continuing pressure to re-evaluate ambient air quality standards stems from research that not only has identified effects at low levels of PM but which also has revealed that reductions in certain components, sources and size fractions may best protect public health. Considerable amount of published information have emerged from toxicological research in recent years. Accumulating evidence has identified additional air quality metrics (e.g. black carbon, secondary organic and inorganic aerosols) that may be valuable in evaluating the health risks of, for example, primary combustion particles from traffic emissions, which are not fully taken into account with PM2.5 mass. Most of the evidence accumulated so far is for an adverse effect on health of carbonaceous material from traffic. Traffic-generated dust, including road, brake and tire wear, also contribute to the adverse effects on health. Exposure durations from a few minutes up to a year have been linked with adverse effects. The new evidence collected supports the scientific conclusions of the World Health Organization Air Quality Guidelines and also provides scientific arguments for taking decisive actions to improve air quality and reduce the global burden of disease associated with air pollution.

Structural signatures of water-soluble organic aerosols in contrasting environments in South America and Western Europe

“…Furthermore, the wet deposition fluxes of atmospheric watersoluble organic matter (WSOM) indicate that it may be an important temporal source of OC to surface waters and, thus, playing an important role in the global carbon cycle (Jurado et al, 2008). From the public health perspective, there are evidences on the association between aerosol OC and adverse health effects (Cassee et al, 2013), with the secondary OC component (more water-soluble) being suggested as a valuable air quality metric. Despite its significance, the multitude of molecular forms, sources, and atmospheric reactivity makes a complete characterization of aerosol WSOC extremely difficult.…”

“…Nevertheless, determining its structural composition is needed to explore its dynamics as well as its sources and formation mechanisms. Furthermore, targeting the chemical composition of aerosol WSOC is also essential for climatic and epidemiological studies, whose results are critical to support and evaluate informed policies on atmospheric pollution reduction at regional and global levels (Cassee et al, 2013;Saffari et al, 2014;Atkinson et al, 2015).…”

Seasonal Trends of Atmospheric PAHs in Five Asian Megacities and Source Detection Using Suitable Biomarkers

“…PAHs cause great concern because of their mutagenic, carcinogenic, and teratogenic properties, and are designated as priority pollutants in the EU (IARC, 1983;Boeuf et al., 2016). They tend to be associated with particulate matter (PM), soils, and sediments (EEA, 2012;Cassee et al, 2013;Cheruiyot et al, 2015). The mass of PM is a widely accepted parameter in air quality protocols (Cassee et al, 2013).…”

“…They tend to be associated with particulate matter (PM), soils, and sediments (EEA, 2012;Cassee et al, 2013;Cheruiyot et al, 2015). The mass of PM is a widely accepted parameter in air quality protocols (Cassee et al, 2013). Suspended PM can be evaluated by its size.…”

Measured performance of filtration and ventilation systems for fine and ultrafine particles and ozone in an unoccupied modern California house

“…Black carbon (BC) is an indicator of diesel particulate matter (DPM), which has been associated with adverse health outcomes independently of PM 2.5 mass (Cassee et al, 2013;Ristovski et al, 2012). Many studies have reported associations between ultrafine particles (UFP, smaller than 100 nm diameter) and health impacts (Beko et al, 2015;Wolf et al, 2015).…”