Edouard Bastarache on sun 2 may 99
Hello Debra,
According to Occupational Medicine by Carl Zenz the size of bacteria
varies from 0.25 to 20 microns. The size of aerosols varies from 0.005
to 50 microns.
According to Infectious Diseases by Shulman, Phair, Peterson and Warren
Mycobacterium tuberculosis measures approximately 0.4 X 4.0 microns.
The crystalline silica, alpha quartz, is the major cause of silicosis
worldwide.
Although the silica polymorphs, cristobalite and tridymite, prove more toxic
for cells and are highly fibrogenic under experimental conditions, these two
mineralogic variants are of more limited health variance.
Quartz particles in the occupational setting range widely in size, but those
less than 1 micron are believed to be the most pathogenic.
Since large particles impact and sediment in the nares and the major
airways,
only relatively small particles enter the acini(lungs)
The size of silica particles retained in the human lung is remarkably
constant,
with median diameters ranging from 0.5 to 0.7 micron.
Later,
Edouard Bastarache
In "La Belle Province"
edouardb@sorel-tracy.qc.ca
http://www.sorel-tracy.qc.ca/~edouardb/
| |
|
