Ammonia in the environment: From ancient times to the present
Publication Type:Journal Article
Source:Environmental Pollution, Volume 156, p.583-604 (2008)
Keywords:Air chemistry, Alchemy, Deposition, Emissions, EPNB, NH3 sal ammoniac, Nushadir
Recent research on atmospheric ammonia has made good progress in quantifying sources/sinks and
environmental impacts. This paper reviews the achievements and places them in their historical context.
It considers the role of ammonia in the development of agricultural science and air chemistry, showing
how these arose out of foundations in 18th century chemistry and medieval alchemy, and then identifies
the original environmental sources from which the ancients obtained ammonia. Ammonia is revealed as
a compound of key human interest through the centuries, with a central role played by sal ammoniac in
alchemy and the emergence of modern science. The review highlights how recent environmental
research has emphasized volatilization sources of ammonia. Conversely, the historical records emphasize
the role of high-temperature sources, including dung burning, coal burning, naturally burning coal seams
and volcanoes. Present estimates of ammonia emissions from these sources are based on few
measurements, which should be a future priority.