In theory, the process from the time the water is treated by the factory to the user must meet strict safety standards and must not contain any toxic substances that pose a health risk. However, in reality, abnormalities in clean water sources can still occur due to problems with the water treatment process, as in the recent Hanoi clean water pollution incident. The most important issue at the moment is how to recognize safe drinking water and how to handle contaminated water sources.

Water pollution is a problem that many agencies are concerned about. Water pollution greatly affects people's lives and health. So how does water pollution occur?