A coin-sized device created by Harvard University researchers mimics the workings of a human lung on a computer chip and may provide a way to test drugs and assess the impact of pollutants.

The see-through lung-on-a-chip contains two chambers separated by a flexible, porous membrane lined with human lung cells on one side and cells from capillary blood vessels on the other. It acts like the air sacs in human lungs, stretching and expanding to duplicate the effects of breathing.

The chip may save drug companies time and money by enabling them to gauge the effects of inhaled medications, said Donald Ingber, the founding director of Harvard's Wyss Institute for Biologically Inspired Engineering in Boston and lead designer of the device. Ingber's work was published this month in Science.

"It's a technological tour de force," said Norman Edelman, chief medical officer of the American Lung Association. "To be able to simulate all those biological functions on a chip is wonderful."

The technology will need to be compared with conventional methods of testing medications in laboratory mice to show it can accurately measure drug effects, Edelman said in a telephone interview yesterday.

- Rob Waters, Bloomberg News