Toxicity of submicron particulate matter

Research studies on wood smoke and other air pollution.

Toxicity of submicron particulate matter

Postby Wilberforce » Fri Feb 22, 2013 7:49 pm

Toxicity of source-oriented ambient submicron particulate matter


BACKGROUND: Extensive literature suggests compelling evidence for a strong relationship between exposure to ambient particulate matter (PM) and cardiopulmonary health impacts. Regional, seasonal and temporal fluctuations in PM concentration and chemical composition can be attributed to a wide variety of distinct point and mobile sources. However, it is unclear how these variations may impact on respiratory and systemic responses. The current National Ambient Air Quality Standard (NAAQS) for PM is based on an average mass concentration, but not on chemical composition. PM mass does not specify sources that contribute to distinct PM characteristics or possible health effects. Sampling of PM from the atmosphere using a source-oriented approach that accounts for atmospheric transformations of pollutants could provide for enhanced understanding of particle source-specific health effects.

OBJECTIVES: To measure pulmonary and systemic markers of inflammation and cytotoxicity elicited by size-specific source-oriented PM collected in Fresno, CA. during the summer and winter seasons.

METHODS: Mice were exposed by oro-pharyngeal aspiration to equivalent doses of ultrafine (UF) and submicron fine (SMF) source-oriented PM. Indicators of pulmonary and systemic inflammation and cytotoxicity were measured 24 hours post-aspiration.

RESULTS: Measures of pulmonary inflammation/cytotoxicity, and hematology differed between source-oriented samples compared to corresponding controls as well as between particle size fractions. Source-oriented PM elicited inflammatory responses appeared to be more significant in the lung compared to the blood. In general, UF PM was more pro-inflammatory compared to SMF PM. Although a number of source-oriented samples produced some degree of biological response in the lungs compared to control, the most biologically responsive samples for the winter season were CV10 (a mix of sources present at night) UF, CV2 (highly processed regional background) SMF and CV3 (EC and OC) SMF, while for the summer season CV2 and CV5 (vehicles) UF and CV 6 (metals) SMF were most biologically reactive. In contrast, hematologic measures were more variable and did not correlate to changes in pulmonary endpoints

CONCLUSIONS AND SIGNIFICANCE: The ability to directly measure the relative toxicity of source-oriented PM increases our understanding of the association between PM sources and adverse health effects. The ultimate goal will be to provide more specific understanding of the composition and sources of PM and their effects to provide greater protection to human health.
• The Surgeon General has determined that there is no safe level of exposure to ambient smoke!

• If you smell even a subtle odor of smoke, you are being exposed to poisonous and carcinogenic chemical compounds!

• Even a brief exposure to smoke raises blood pressure, (no matter what your state of health) and can cause blood clotting, stroke, or heart attack in vulnerable people. Even children experience elevated blood pressure when exposed to smoke!

• Since smoke drastically weakens the lungs' immune system, avoiding smoke is one of the best ways to prevent colds, flu, bronchitis, or risk of an even more serious respiratory illness, such as pneumonia or tuberculosis! Does your child have the flu? Chances are they have been exposed to ambient smoke!
User avatar
Posts: 6093
Joined: Wed Jul 25, 2007 11:36 pm
Location: USA

Return to Particle Pollution Research

Who is online

Users browsing this forum: No registered users and 2 guests