Knowledge Bit:Breath Real Deep!

Depending on the environment that you live in,
you have just inhaled the following:

oxygen 21 %

Nitrogen 78 %

Carbon Dioxide less than 1 %

Traces of other gases and contaminants which may
include exhaust fumes, smoke from factories and smog.
These contain cancer causing benzene, ammonia and
formaldehyde. Also part of the mix is tiny bits of
insect parts, space dust, fungal spores, dust mites,
human skin cells, fabric particles, paint particles
and a lot more.