Cell phone use dangerous, on foot or while driving

Two new studies show that talking on the phone while traveling, whether you're driving or on foot, is increasing both pedestrian deaths and those of drivers and passengers, and recommend crackdowns on cell use by both pedestrians and drivers.

The new studies, lead-authored by Rutgers University, Newark, Economics Professor Peter Loeb, relate the impact of cell phones on accident fatalities to the number of cell phones in use, showing that the current increase in deaths attributed to cell phone use follows a period when cell phones actually helped to reduce pedestrian and traffic fatalities. However, this reduction in fatalities disappeared once the numbers of phones in use reached a "critical mass" of 100 million, the study found.

These studies looked at cell phone use and motor vehicle accidents from 1975 to 2002, and factored in a number of variables, including vehicle speed, alcohol consumption, seat belt use, and miles driven. The studies found the cell phone-fatality correlation to be true even when weighing in factors such as speed, alcohol consumption, and seat belt use.

Before this critical mass was reached, cell phones actually had a life-saving effect because both pedestrians and drivers could call for help quickly in the event of an accident.