Nitrous oxide (N2O) is a clear, colorless gas with a slightly sweet odor that is emitted to the atmosphere by natural and human industrial sources. Industrial sources of nitrous oxide include agricultural soil management, fossil fuel combustion, and some acid production. Natural emissions of nitrous oxide, which stem from biological processes in soil and water, contribute about 60% of total global annual emissions. Nitrous oxide traps heat over 300 times more effectively than carbon dioxide, making it an important greenhouse gas. The concentration of nitrous oxide in the atmosphere has increased from about 260 to 315 pbb since the onset of the Industrial Revolution. The atmospheric residence time of nitrous oxide is about 120 years. Information source: U.S. EPA.
Global Greenhouse Gas Levels
The major greenhouse gases are globally mixed and their current levels have greatly exceeded their pre-industrial levels. The current levels of greenhouse gases are all considered unhealthy.
See evidence of just how drastically their levels have increased in the ice core record.
There are no known direct health impacts associated with atmospheric nitrous oxide. However, because nitrous oxide is a greenhouse gas, it can impact health indirectly with rising concentrations contributing to global climatic change. Information source: U.S. EPA.