Major Pollutants from Automobiles

Jump in the car, start your engine, and you’re off. But do you give any thought to what’s coming out of the tailpipe as you go about your drive? Here’s what your beloved car is producing:

Carbon dioxide is the dominant greenhouse gas that causes global warming. The effects of global warming are uncertain, but they potentially include disruption of global weather patterns and ecosystems, flooding, severe storm, and droughts.

Carbon monoxide, when inhaled, combines with hemoglobin in our blood, impairing the flow of oxygen to our brain and other parts of the body. Carbon monoxide is colorless, odorless, and poisonous even to healthy people (at high levels in the air). It can seriously affect people with heart disease, and can affect the central nervous system. Motor vehicles remain the number one source of carbon monoxide pollution in many countries.

Sulphur oxides contribute to respiratory illness, particularly in children and the elderly, and aggravate existing heart and lung diseases. It contributes to the formation of acid rain, which damages trees, crops, and buildings; and makes soils, lakes, and streams acidic.

Oxides of nitrogen (NOx) are noxious pollutants. They are lung irritants, which react with compounds in the air to cause acid rain and ozone (the main reason for smog). NOx is one of the main ingredients involved in the formation of ground-level ozone (which can trigger serious respiratory problems).
> What’s the difference between oxides of nitrogen and nitrous oxide?

Particulate matter, consisting of tiny particles of smoke, soot and dust—primarily from engines, car parts, tires, and diesel exhaust—are an established cause of lung problems, from shortness of breath to worsening of respiratory and cardiovascular disease, damage to lung tissues, and cancer. The EPA estimates that particulate pollution kills more than 60,000 people per year. In addition, particulates are associated with increased hospital admissions and emergency room visits for people with heart and lung disease, as well as work and school absences. Particulates can travel deep into the lungs, or in smaller form, directly into the bloodstream.

Hydrocarbons, in their many forms, are directly hazardous, contributing to what are collectively called "air toxics." These compounds directly irritate the lung and other tissues, can cause cancer, contribute to birth defects, and cause other illnesses.

Lead damages organs, affects the brains, nerves, heart, and blood. Although overall blood lead levels have decreased since 1976, urban areas with high levels of traffic or industrial facilities that burn fuel may still have high lead levels in air. In 1999, ten areas of the country did not meet the national health-based air quality standards for lead.

Rolling Up Your Window Won’t Help

Exposure to some car pollutants may be much higher inside your car than outside. Commuters driving in rush hour get the highest exposure, often from pollutants emitted by vehicles ahead of them. You are basically driving in and through—and contributing to—a lethal cocktail of air pollution.