The Durk Pearson & Sandy Shaw®
Life Extension NewsTM
Volume 8 No.
1 • January 2005
Risk of Heart Attack and Exposure to Traffic
A new paper reports that exposure to traffic increases the risk of a heart attack within one hour afterward by 2.92 times compared to nonexposed individuals. The authors found that “The time the subjects spent in cars, on public transportation, or on motorcycles or bicycles was consistently linked with an increase in the risk of myocardial infarction.” The study was based on 691 subjects from the Cooperative Health Research in the Region of Augsburg Myocardial Infarction Registry in Augsburg (southern Germany) for the period from February 1999 to July 2001. Data on subjects’ activities during the period preceding the heart attack were obtained with the use of patient diaries. The authors also note that “… the estimated risks were larger for morning and afternoon hours than for night hours, when the density of the traffic is low. … Particulate matter is considered to be of primary concern.”
Antioxidants may be protective against the inflammatory effects of roadway particulate pollution. One paper reports that lung inflammation is a key response to increased levels of particulate air pollution. They tested the ability of N-acetylcysteine (50 mg/kg ip) to protect against lung inflammation in a rat model of short-term exposure to concentrated ambient particles (CAP). They found that rats breathing the CAPs suffered severe oxidative stress associated with increased numbers of polymorphonuclear leukocytes (an inflammatory response) in bronchoalveolar lavage and slight lung edema. CAPs-exposed animals showed slight bronchiolar inflammation and thickened blood vessels in the bronchioles, which effects were prevented by N-acetylcysteine (NAC). NAC prevented accumulation of oxidants but only partially prevented accumulation of oxidized proteins (carbonyls).
The authors concluded that “The observed preventive effect of NAC suggests that treatment with low doses of this antioxidant could be used to ameliorate the toxic effects of particulate air pollution.”
Watch out for indoor particulate pollution too.
- Peters et al. Exposure to traffic and the onset of myocardial infarction. New Engl J Med 351:1721-30 (2004).
- Rhoden et al. N-Acetylcysteine prevents lung inflammation after short-term inhalation exposure to concentrated ambient particles. Toxicol Sci 79:296-303 (2004).