Changes in matter are all harmful to humans and other living things.

Earthquakes and volcanic eruptions cause natural changes in matter.

Freezing of food helps prolong the shelf life of other products.

Decaying of organic matter helps return nutrients back to the soil.

Eating spoiled food will not cause any harm to the person consuming it.

Diseases such as hepatitis and cholera are caused by air pollution.

Climate change may lead to other environmental  issues such as drought and flood.

Water pollution causes destruction of coral reefs.

Modernization can both be useful and harmful to humans.

The main cause of pollution is human activities.