How can you know there has been water pollution in the river or at sea, other than by looking at the color of the water? Consider the following explanation. Water pollutants can be distinguished in three types, physical contaminants, chemical and biological, such as bacteria, viruses, household waste, chemicals that dissolve in water (acids, toxic metals and other compounds), inorganic fertilizer, radioactive materials and organic chemicals (oil, gasoline, plastic).
To determine whether the river or sea is polluted or not, we can find out through the following indicators:
- The change of color, smell and taste of water. In normal condition, water will not be colored, so that it looked clear and crisp, but it did not apply an absolute, it is often toxic substances contained in industrial waste materials that do not cause discoloration of water. Odor problem in water environment can be used absolutely as one sign of contamination. If the water has a sense, it is means there is an addition material on the water and change the hydrogen ion concentration and pH of the water.
- The change of water temperature. When hot water directly discharged into the environment will disrupt the lives of aquatic animals and other microorganisms.
- The increased radioactivity in the water. Radioactive materials from a variety of activities can cause various kinds of biological damage if not handled properly, either direct effects or delayed effects.
- Incidence of sediment, colloidal, dissolved materials. Solid waste material, before going down to the bottom of the river will float in water with colloidal, thus blocking the entry of sunlight into the water layer. Though sunlight is needed by microorganisms to perform photosynthesis.
- The change of pH or hydrogen ion concentration. Normal water that eligible for a life has a pH ranging between 6.5 to 7.5.
- The presence of microorganisms. Microorganisms play an important role in the degradation process of waste material from domestic or industrial waste.
