Exhaust gas
According to the type of engine, it is discharged into the atmosphere through an exhaust pipe, flue gas stack, or propelling nozzle.
It is a major component of motor vehicle emissions (and from stationary internal combustion engines), which can also include crankcase blow-by and evaporation of unused gasoline.
Motor vehicle emissions are a common source of air pollution and are a major ingredient in the creation of smog in some large cities.
Exhaust gas temperature (EGT) is important to the functioning of the catalytic converter of an internal combustion engine.
[6] Exhaust gas from an internal combustion engine whose fuel includes nitromethane will contain nitric acid vapour, which is corrosive, and when inhaled causes a muscular reaction making it impossible to breathe.
Mono-nitrogen oxides NO and NO2 (NOx) (whether produced this way or naturally by lightning) react with ammonia, moisture, and other compounds to form nitric acid vapor and related particles.
Small particles can penetrate deeply into sensitive lung tissue and damage it, causing premature death in extreme cases.
When oxides of nitrogen (NOx) and volatile organic compounds (VOCs) react in the presence of sunlight, ground level ozone is formed, a primary ingredient in smog.
In 2011, 52% of carbon monoxide emissions were created by mobile vehicles in the U.S.[24] Chronic (long-term) exposure to benzene (C6H6) damages bone marrow.
[25][26] The health effects of inhaling airborne particulate matter have been widely studied in humans and animals and include asthma, lung cancer, cardiovascular issues, premature death.
In 2022, British testing specialist Emissions Analytics estimated that the 300 million or so gasoline vehicles in the US over the subsequent decade would emit around 1.6 septillion harmful particles.
Motor vehicle CO2 emissions are part of the anthropogenic contribution to the growth of CO2 concentrations in the atmosphere which according to the vast majority of the scientific community is causing climate change.
Air pollution from fossil fuel use by industry, power generation, and transportation is estimated to kill over 5 million people each year.
[40] A 2013 study by the Massachusetts Institute of Technology (MIT) indicates that 53,000 early deaths occur per year in the United States alone because of vehicle emissions.
[citation needed] Concentrations of pollutants emitted from combustion engines may be particularly high around signalized intersections because of idling and accelerations.
