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                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: TUESDAY, January 26, 1993                   TAG: 9301260018
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A10   EDITION: METRO 
SOURCE: The New York Times
DATELINE:                                 LENGTH: Short

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NOW, BIOSPHERIANS CAN BREATHE EASIER

Eager to avoid a medical emergency, leaders of Biosphere 2 in Arizona have begun pumping tons of pure oxygen into the miniature glass-enclosed world inhabited by eight humans.

Oxygen levels have risen from 14.5 percent to 17.5 percent and at the operation's end will stand at about 19 percent, still shy of the 21 percent found at sea level.

Before the oxygen was added, the four men and four women in the 3.15 acres of glass domes in the foothills north of Tucson were breathing rarefied air similar to that found at an altitude of about 13,400 feet. The thin air left the crew members fatigued and achy; they sometimes gasped for breath.

Project leaders say the Biospherians, as they call themselves, are already breathing easier as they enjoy a richer atmosphere. When the 19 percent goal is reached, the air's oxygen content will equal that found at about 6,400 feet.

When the $150 million Biosphere project began in September 1991, it was billed as a utopian planet in a bottle, where everything would be recycled, as its eight inhabitants lived for two years in the first large self-contained habitat for humans.

But slowly, mysteriously, breathable oxygen disappeared. Some scientists believed it was binding with the soil. The riddle is still being studied.

Project leaders say the scientific goals of the project are untainted, since the exact quantity of added oxygen is known and can be factored into environmental studies and equations. But some critics say the whole point of the recycling venture is now discredited.

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