But why is this?
This is because toxic compounds can adsorb – that is, stick – to the surface of the suspended
colloid. The more colloids there are, the more toxic the water can become. These toxic
materials in bacteria can cause cholera, salmonelosis, hepatitis A, dysentery and E-Coli
infection. These illnesses affect and kill millions of people in the world and are especially
dangerous to children whose weak immune system can’t provide adequate defence.
Fortunately we can do something about this. One of the very practical ways to clean this
turbid water is called flocculation.