What are the pollutants in vehicle exhaust emissions?
3 Answers
Vehicle exhaust emission standards are based on the China IV standard. The following are the harmful substances in vehicle exhaust and their hazards: Harmful substances in vehicle exhaust: Vehicle exhaust contains hundreds of different compounds, including pollutants such as solid suspended particles, carbon monoxide, carbon dioxide, hydrocarbons, nitrogen oxides, lead, and sulfur oxides. Hazards of vehicle exhaust: While directly harming human health, exhaust emissions also have profound impacts on the environment. Sulfur dioxide in exhaust has a strong irritating odor and, when reaching certain concentrations, can lead to "acid rain," causing soil and water acidification and affecting the growth of crops and forests.
I've found that vehicle exhaust pollutants are truly harmful to the environment. The main culprits include carbon monoxide, which can cause oxygen deprivation and poisoning at high concentrations; nitrogen oxides that form acid rain, damaging trees and lakes; hydrocarbons creating photochemical smog, turning cities into hazy landscapes; particulate matter like fine dust that penetrates lungs, triggering respiratory diseases; and carbon dioxide - while less toxic than others, massive emissions accelerate global warming, leading to more frequent heatwaves and heavy rains. In daily driving, these pollutants accumulate in urban air, creating smoggy days that force people to wear masks outdoors. Personally, I try to reduce short-distance driving by walking or cycling more, and ensure regular engine maintenance for efficient combustion, which can significantly cut emission sources.
I've seen plenty of exhaust issues during car repairs. Pollutants like hydrocarbons come from unburned gasoline fumes; carbon monoxide results from improper fuel-air mixture; nitrogen oxides form through high-temperature engine reactions; and particulate matter consists of floating soot from diesel exhaust. These emissions not only cause black smoke but also pollute roadside air, making neighbors complain about coughing. I recommend checking spark plug and air filter replacement frequency, using qualified fuel to control combustion temperature, and avoiding speeding or sudden acceleration to significantly reduce emissions. Older vehicles perform worse – upgrading to a newer model with a catalytic converter makes a big difference.
