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Chapter 8
Water Pollution
8.1 SOURCES AND IMPACTS OF WATER POLLUTION
Urban agglomerations, transport, and industrial and agricultural activities
pollute sea, underground and freshwater with their air and solid waste,
but primarily their liquid waste. Urban wastewater is carried by sewers
and constitutes the bulk of a city’s liquid waste. It contains an abundance
of microorganisms, organic compounds, certain inorganic salts, mainly
salts of ammonium, nitrogen and phosphorus as well as small quantities
of other compounds. Marine transport may pollute ecosystems with petroleum products. As a rule, liquid waste from large or small industrial units
contain pollutants similar to those in urban wastewater, but sometimes
it also contains toxic organic compounds, various metals such as lead
and mercury, or radioactive elements. Some industrial wastes damage the
aquatic environment because of their high temperature. Agricultural runoff
pollutes the aquatic environment mainly with inorganic salts from fertilizers, as well as toxic substances from pesticides. Urban activities also pollute
rainwater, which when it runs off city streets is loaded with a wide variety
of pollutants such as lead and cadmium, generally in small concentrations.
All types of liquid wastes end up in receiving water, which may be on the
surface or underground.
The adverse effects of water pollution may be divided into the following
categories and involve a wide variety of pollutants. The action of each pollutant may refer to one and/or all the categories of impact:
• Ecological impacts, when pollutants cause disruptions to aquatic ecosystems
• Aesthetic impacts, when pollution causes a disagreeable appearance,
smell, colour or murkiness in a body of water (sea, lake, river), degrading the landscape and preventing its use for recreational purposes
• Hygienic impacts, when water (surface or underground) becomes a carrier
of pathogenesis or toxicity for the people and animals who either use
the water for drinking or swimming or use aquatic organisms for food
DOI: 10.1201/b14609-8
Chapter 8
Water Pollution
8.1 SOURCES AND IMPACTS OF WATER POLLUTION
Urban agglomerations, transport, and industrial and agricultural activities
pollute sea, underground and freshwater with their air and solid waste,
but primarily their liquid waste. Urban wastewater is carried by sewers
and constitutes the bulk of a city’s liquid waste. It contains an abundance
of microorganisms, organic compounds, certain inorganic salts, mainly
salts of ammonium, nitrogen and phosphorus as well as small quantities
of other compounds. Marine transport may pollute ecosystems with petroleum products. As a rule, liquid waste from large or small industrial units
contain pollutants similar to those in urban wastewater, but sometimes
it also contains toxic organic compounds, various metals such as lead
and mercury, or radioactive elements. Some industrial wastes damage the
aquatic environment because of their high temperature. Agricultural runoff
pollutes the aquatic environment mainly with inorganic salts from fertilizers, as well as toxic substances from pesticides. Urban activities also pollute
rainwater, which when it runs off city streets is loaded with a wide variety
of pollutants such as lead and cadmium, generally in small concentrations.
All types of liquid wastes end up in receiving water, which may be on the
surface or underground.
The adverse effects of water pollution may be divided into the following
categories and involve a wide variety of pollutants. The action of each pollutant may refer to one and/or all the categories of impact:
• Ecological impacts, when pollutants cause disruptions to aquatic ecosystems
• Aesthetic impacts, when pollution causes a disagreeable appearance,
smell, colour or murkiness in a body of water (sea, lake, river), degrading the landscape and preventing its use for recreational purposes
• Hygienic impacts, when water (surface or underground) becomes a carrier
of pathogenesis or toxicity for the people and animals who either use
the water for drinking or swimming or use aquatic organisms for food
DOI: 10.1201/b14609-8