Ammonia

Ammonia (NH3) is a chemical compound, a toxic gas comprised of the element nitrogen and three molecules of hydrogen.

In the year 2365, the Federation starship USS Enterprise (NCC-1701-D) performed sensor scans of planet Theta 116 VIII and found weather activity in the atmosphere described as ammonia tornadoes. 

The atmosphere of Marijne VII leaked into the hull of the damaged USS Raman in 2370. Upon finding the Raman trapped in the atmosphere, the Enterprise-D used an interface probe controlled by Geordi La Forge to detect ammonia and methane in a ship's corridor.