Emissions of N2O in Canada in 1990 were estimated at 92 kilotonnes. Fossil fuel combustion accounted for about 52% of the total, followed by industrial processes (36%), and fertilizer use (12%).
Nitrous oxide is not controlled in the USA as the clean air act in the USA was written in 1970 to control smog, not global warming.The agreement at the [Kyoto Climate Convention] in December 1997 to reduce emissions believed to cause global warming has not been ratified by the US senate and no implementing rules have been written.