f881c3e3_Air_Alternatives__A_Fact_Sheet__Its_Sources
[Pollutant] Carbon Monoxide [Health Effects] Replaces oxygen in the bloodstream; aggravates heart disease; impairs alertness. [Its Sources] 
Combustion processes, such as in gas mowers, cars & industry. Any burning of organic material.
Cleaner Air: Mowing Emissions and Clean Air Alternatives. A Fact Sheet
Its Sources