National Geographic defines pollution as the introduction of harmful materials into the environment.
Pollution is caused by a lot of things such as car and truck exhaust, fumes, factories, dust, pollen, mold spores, ect...
Pollution isn't only in the air, but also in the water and in the ground.
Pollution is one of the biggest problems nowadays,...

A carbon footprint is a measure which expresses how much greenhouse gas an activity, a product or a service produce.The gases which we have to include when we calculate the carbon footprint have been defined by the international protocol of Kyoto (enacted on 16th February 2005). They are:

Acoustic pollution is often underestimated, but it's a really big problem. In fact, scientists notice that there are more people who suffer from upset sleep, myocardial, stroke, hypertension and cardiovascular illness in chaotic and noisy cities than in quiet places. Obviously acoustic pollution causes irreversible hearing problems.

Light pollution is the alteration of the natural amount of light present in the night environment caused by the introduction of artificial light.

Ground pollution is the alteration of chemical-physical and biological equilibrium of the soil, but also the tendency towards erosion and landslide.

Water pollution is the contamination of lakes, seas, rivers, aquifers etc. by inputs of substances that alter their quality and condition.