Named Water Pollutants

Different pollutants affect water in different ways. A useful classification is chemical pollutants + biological pollutants + physical pollutants. Important examples include sewage, excess nutrients, toxic metal compounds, pesticides, pathogens, sediments and industrial chemicals. Pollutant source → water-quality change → biological or chemical effect.

Water can look clear and still be polluted. It may contain germs or harmful dissolved chemicals that cannot be seen. Important pollutant groups include sewage, nutrients, metals, pathogens, sediment and industrial chemicals.

Pollutants should be identified by source, concentration and effect. Nutrients are necessary for life, for example, but excessive nutrient concentrations can become environmentally harmful.

Pollution impact depends on more than total concentration. Chemical speciation, persistence, mobility, bioavailability and interaction with sediments or organisms strongly affect environmental behaviour. Clear water may still carry dissolved toxins or pathogens.

Sewage adds organic matter and pathogens · Nutrients pollute when excessive · Some metals are toxic · Pathogens cause disease · Sediment increases turbidity · Clear water is not automatically safe · Concentration and chemical form matter