Device may catch lying smokers

A simple device for detecting carbon monoxide in the blood may help doctors get an honest answer out of patients who smoke, U.S. researchers have found.

The device, called a pulse cooximeter, is typically used to test for carbon monoxide levels in firefighters, but it can also detect carbon monoxide levels in people who smoke.

“There is no good way to screen people for smoking,” said Dr. Sridhar Reddy, a lung specialist in St. Clair, Mich., who presented the study last week at a scientific meeting of the American College of Chest Physicians in Chicago, along with his 16-year-old son, Ashray.

Reddy had encouraged Ashray to take on the study as a school science project.

The pulse cooximeter reads percentages of poisoned blood through a light that is shined through the fingernail.