Effect of hourly concentration of particulate matter ...

Research studies on wood smoke and other air pollution.

Effect of hourly concentration of particulate matter ...

Postby Wilberforce » Thu Mar 10, 2011 7:07 pm

Effect of hourly concentration of particulate matter on peak expiratory flow in hospitalized children: A panel study
Shin Yamazaki, Masayuki Shima, Michiko Ando, Hiroshi Nitta, Hiroko Watanabe and Toshiyuki Nishimuta
Abstract (provisional)

Little information is available on the possible association between hourly short-term air pollution and peak expiratory flow (PEF) in asthmatic children.

PEF was measured twice daily, from October through December, 2000, in 17 children aged 8 to 15 years hospitalized with severe asthma. A total of 1198 PEF measurements were made at 7 a.m. and 1175 at 7 p.m. Measurements were conducted immediately prior to medication under the guidance of trained nurses. PEF changes were estimated in 10-ug/m3 increments of particulate matter with a 50% cut-off aerodynamic diameter of [less than or equal to]2.5 um (PM2.5), with adjustment for sex, age, height, and temperature. Lagged-hour exposures of up to 24 hours were examined.

Increased 24-hour mean concentration of PM2.5 was associated with a decrease in both morning and evening PEF (-3.0 l/minute; 95%CI: -4.6, -1.4 and -4.4 l/minute; 95%CI: -7.1, -1.7, respectively). In addition, hourly concentrations of PM2.5 and PEF showed a significant association between some lags of PM2.5 and PEF. Effect size was almost -3 l/minute in both morning and evening PEF for an hourly PM2.5 concentration of 10 mug/m3 in several lags. Even after adjustment for other air pollutants, some of the significant associations with PEF remained.

Among hospitalized children with severe asthma, increased hourly concentration of PM2.5 was associated with a decrease in PEF.
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• 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!
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