SCIENCE

Notebook

New Pollution Effects Observed

Here is one more reason to dread the rat race.

Rats exposed to highway pollution for several hours in an experiment by University of Rochester researchers experienced a drop in heart rate and impairment of the nervous system. The rats, old and prone to high blood pressure, rode in a mobile laboratory for six hours on a New York interstate, inhaling vehicle emissions that motorists would be exposed to along the 320-mile route.

Tests showed that the creatures experienced up to a 10 percent decline in their heart rate and that the effect of the pollution lasted up to 14 hours.

The researchers said the findings, published in January's issue of Inhalation Toxicology, help explain why on smoggy days hospitals in urban areas typically see a spike in visits to the emergency room because of heart attacks.

The findings also are in line with a recent European study that showed that people who are exposed to air pollution while riding a bus or riding a bicycle to work are more likely to have a heart attack within an hour of their commute.

"The fact that exposure to air pollution can change the heart rate, independent of other factors, is a cause for concern," said Alison Elder, the lead researcher. "It's important to understand that these changes are taking place outside of the lung. Air pollution is either having a direct effect on the heart in rats or is altering something within the circulatory system."

-- Christopher Lee

Smelling Food Could Speed Aging

Plug your nose, live a little longer. That's the take-home message from a study showing that mere whiffs of food can shorten a fly's life.

Studies in worms, flies, mice and monkeys have shown that aging can be slowed by cutting way back on calories consumed. Loosely organized experiments in humans are ongoing.

But is it food itself that shortens life? Or might it be the mere perception of food -- the biochemical stimulation that occurs when food odors tickle olfactory nerves?