Comparative Toxicity of Size-Fractionated Airborne Particulate Matter Obtained from Different Cities in the United States

Abstract

Hundreds of epidemiological studies have shown that exposure to ambient particulate matter (PM) is associated with dose-dependent increases in morbidity and mortality. While early reports focused on PM less than 10 microm (PM10), numerous studies have since shown that the effects can occur with PM stratified into ultrafine (UF), fine (FI), and coarse (CO) size modes despite the fact that these materials differ significantly in both evolution and chemistry. Furthermore the chemical makeup of these different size fractions can vary tremendously depending on location, meteorology, and source profile. For this reason, high-volume three-stage particle impactors with the capacity to collect UF, FI, and CO particles were deployed to four different locations in the United States (Seattle, WA; Salt Lake City, UT; Sterling Forest and South Bronx, NY), and weekly samples were collected for 1 mo in each place. The particles were extracted, assayed for a standardized battery of chemical components, and instilled into mouse lungs (female BALB/c) at doses of 25 and 100 microg. Eighteen hours later animals were euthanized and parameters of injury and inflammation were monitored in the bronchoalveolar lavage fluid and plasma. Of the four locations, the South Bronx coarse fraction was the most potent sample in both pulmonary and systemic biomarkers, with a strong increase in lung inflammatory cells as well as elevated levels of creatine kinase in the plasma. These effects did not correlate with lipopolysaccharide (LPS) or total zinc or sulfate content, but were associated with total iron. Receptor source modeling on the PM2.5 samples showed that the South Bronx sample was heavily influenced by emissions from coal fired power plants (31%) and mobile sources (22%). Further studies will assess how source profiles correlate with the observed effects for all locations and size fractions.

A rapid assessment of the impact of hazard reduction burning around Sydney, May 2016

“…In a different study, these effects were attributed to the insoluble components of the mixture and are not caused by an endotoxin (Wegesser & Last, 2008). The intratracheal exposures in rats and mice, as well as in vitro studies, suggest that similar effects can be observed for coarse and fine PM in the bioassays of lung cells (Gerlofs-Nijland et al, 2007;Halatek et al, 2011;Gilmour et al, 2007;Jalava et al, 2008;Happo et al, 2010) and that coarse PM can be even more hazardous than fine PM. Again, given that the deposition efficiency and pattern of coarse and fine PM differ largely, the health outcomes in a population can differ at equal mass exposures.…”

Interleukin 13– and Interleukin 17A–Induced Pulmonary Hypertension Phenotype Due to Inhalation of Antigen and Fine Particles from Air Pollution

“…This PM 2.5 was provided by Dr. Terry Gordon's laboratory at the NYU Medical Center, resuspended, and ultrasonicated before use. 35 This fraction was chosen because the size of <2.5 μm in diameter allows the particles to travel via the airways into the alveoli. The dose chosen was at half the concentration of the dose reported to induce significant airway inflammation using PM 2.5 sampled in New York City, 35 Beijing, 36 and Baltimore.…”

“…35 This fraction was chosen because the size of <2.5 μm in diameter allows the particles to travel via the airways into the alveoli. The dose chosen was at half the concentration of the dose reported to induce significant airway inflammation using PM 2.5 sampled in New York City, 35 Beijing, 36 and Baltimore. Antigen immunization and exposure to antigen and PM Animals were primed and challenged with antigen as described elsewhere 17,18 and schematically presented in Figure 2A.…”

Comments on Gilmour et al., “Comparative Toxicity of Size-Fractionated Airborne Particulate Matter”

“…The CMB methodology is referred to an unpublished paper for more details (Duvall et al, 2007). Unfortunately, this manuscript as currently available from its authors (Fall of 2007) is no more explanatory of this CMB application than Gilmour et al…”