Industrial pollutants are substances that are released into the environment as a result of industrial activities. The two most common industrial pollutants are ASH and SMOG. ASH is a by-product of burning fossil fuels, such as coal, and is composed of tiny particles that can be inhaled and cause respiratory problems. SMOG is a combination of smoke and fog that is created when pollutants from factories and vehicles mix with air. It can cause eye irritation, headaches, and other health problems.