Canker sores may not be a serious condition, but they do require care and occasional medication. Find out what you can do to prevent and treat them at home.

The surrounding influences which are now included in the meaning of 'the environment' are the air that we breathe, the water we drink or swim in, our homes, numbers of people, traffic, noise, streets, stores, parks, countryside, seashore, wildlife, factories, farming and mining.