The association of particulate air metal concentrations with heart rate variability.
Numerous studies show an association between particulate air pollution and adverse health effects. Particulate matter is a complex mixture of elemental carbon, ammonium, sulfates, nitrates, organic components, and metals. The mechanisms of action of particulate matter less than or equal to 2.5 micro m in mean aerodynamic diameter (PM(2.5)), as well as the constituents responsible for the observed cardiopulmonary health effects, have not been identified. In this study we focused on the association between the metallic component of PM(2.5) and cardiac autonomic function based on standard heart rate variability (HRV) measures in an epidemiologic study of boilermakers. Thirty-nine male boilermakers were monitored throughout a work shift. Each subject wore an ambulatory electrocardiogram (Holter) monitor and a personal monitor to measure PM(2.5). We used mixed-effects models to regress heart rate and SDNN index (standard deviation of the normal-to-normal) on PM(2.5) and six metals (vanadium, nickel, chromium, lead, copper, and manganese). There were statistically significant mean increases in the SDNN index of 11.30 msec and 3.98 msec for every 1 micro g/m(3) increase in the lead and vanadium concentrations, respectively, after adjusting for mean heart rate, age, and smoking status. Small changes in mean heart rate were seen with all exposure metrics. The results of this study suggest an association between exposure to airborne metals and significant alterations in cardiac autonomic function. These results extend our understanding of the adverse health effects of the metals component of ambient PM(2.5).
Occupational Health Program, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
Shannon R
SR
Magari
Joel
J
Schwartz
Paige L
PL
Williams
Russ
R
Hauser
Thomas J
TJ
Smith
David C
DC
Christiani
D000328:Adult; D016902:Air Pollution, Indoor / Q000009:adverse effects*; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D019570:Inhalation Exposure; D008297:Male; D008670:Metals / Q000009:adverse effects*; D008875:Middle Aged; D016273:Occupational Exposure; D010316:Particle Size
D008670:Metals