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Which pollutants are commonly found in wastewater?
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wastewater treatment
All the sewers in your neighborhood end up here.
Wastewater contains a diverse array of contaminants, which are typically categorized into physical, chemical, and biological groups. The specific composition depends heavily on the source of the wastewater.1
Common Pollutants
- Biological Pollutants: Domestic sewage is a primary source of pathogens, including bacteria, viruses, and protozoa, which pose significant risks to public health.21
- Organic Matter: Wastewater often contains putrescible organic substances that deplete dissolved oxygen in receiving waters as they decompose, endangering aquatic life. It may also include synthetic organic chemicals and active pharmaceutical ingredients.21
- Plant Nutrients: Nitrates and phosphates are common, often originating from municipal sewage and agricultural runoff. These nutrients can trigger eutrophication, leading to harmful algal blooms and oxygen-deficient conditions.234
- Toxic and Inorganic Substances: This category includes heavy metals (such as lead and mercury), pesticides, radioactive substances, oil, and sediments.561
Effective wastewater treatment is essential to protect public health and the environment by removing these pollutants before water is discharged into natural bodies of water.2