The heart doesn't pound with fear or race with excitement because a person wants it to. These things happen involuntarily, triggered by commands from the autonomic nervous system. A new study reports that breathing high concentrations of fine dust elicits subtle changes in autonomic control of heart rhythms.
The finding suggests why certain dust-generating jobs may increase a worker's risk of cardiovascular disease, including heart attacks.
David C. Christiani and his colleagues at the Harvard School of Public Health in Boston recruited 40 healthy men to wear devices that continuously recorded their heartbeats on several days. All were boilermakers–some apprentice welders and others seasoned journeyman–assigned to the repair of massive electric-utility boilers.