The Moon: closer to asbestos than to green cheese

Nasa's Lunar Airborne Dust Toxicity Advisory Group (LADTAG), which includes medical doctors as well as scientists from UT, have been working to characterise the dust's properties.

"I've been working on lunar samples for 35 years and I have looked at fractions down to a few microns (millionths of a metre), but never anything less," said Professor Larry Taylor, director of the Planetary Geosciences Institute at Tennessee.

"The medical doctors are interested in things that are less than about three microns.

"So we did some particle size determinations and discovered that a very large portion of lunar soil is potentially dangerous, approximately 1-3% of the total soil by weight."

And this is really wild:

The team at the University of Tennessee . . . determined that most of the fine particles in lunar dust are composed of glass formed through the impact of micrometeorites on the surface of the Moon. But the glass also contains metallic iron grains, much like that in a carpenter's nail and measuring just 10-20 nanometres in size.

These grains, called "nano-phase iron", are so small that, if inhaled, some would pass directly from the lungs into the blood circulation.

Once in the blood, the iron could "de-energise" the haemoglobin molecule which carries oxygen to the body's tissues. If enough gets dissolved in the blood, it could produce effects similar to carbon monoxide poisoning. . .

In addition, when some fine dust particles are examined under the microscope, they can be seen to be filled with holes - like Swiss cheese.

These vesicles give them a much larger surface area to react with the lung tissue, says Dr Yang Liu, a postdoctoral research associate at the University of Tennessee.

Read the full article here, including much else about the strange properties of lunar dust.

Posted by David on March 18, 2007 1:23 PM