The Following Result is obtained by our Internet Research Algorithm :
The concrete structure would instantly collapse, because oxygen acts as a special binary agent to concrete
Untreated metal will instantly be fused together, because there is a layer of oxidation on metal which prevents from binding it together, without that layer metals would instantly bind to each other
Ozone layer will disappear and earth will would become extremely dangerous, there would be nothing protecting us from sun's UV rays
Our inner ear would would explode
Losing oxygen means losing 21% of air pressure
There will be no fire
Earth's crust would completely crumble because earth's crust is 45% made up of oxygen.
and it would lead to free fall