Water Pollution

Hey, Guys;

We all know there is large water scarcity in our state. Water pollution is defined as "the change in physical, chemical, and as well as biological characteristics of water which may cause harmful effects on human beings and aquatic life".The pollutants include sewage, industrial chemicals and effluents, oil and other wastes. Besides, chemicals from the air dissolved in the rainwater, and fertilizers, pesticides, and herbicides leached from the land also pollute water.

Types, effects, and sources (causes) of water pollution

Water pollution is any chemical, biological and physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses

• Infectious Agents

Example: Bacteria, viruses, protozoa, and parasitic worms.

Human sources (causes): Human and animals waste.

Effects: Variety of diseases.

• Oxygen-Demanding Waste (Dissolved oxygen)

Example: Organic wastes such as animal manure and plant debris that can be decomposed by aerobic (oxygen-requiring) bacteria.

This degradation consumes dissolved oxygen in the water. Dissolved oxygen (DO) is the amount of oxygen dissolved in a given quantity of water at a particular pressure and temperature.

The saturated point of DO varies from 8-15 mg/lit

Human sources (cause): Sewage, animal feedlots, paper mils, and food processing facilities.

Effects: Large populations of bacteria decomposing these waste can degrade water quality by depleting the water of dissolved oxygen. This causes fish and other forms of oxygen-consuming aquatic life to die.

• Inorganic Chemicals

Example: Wter soluble inorganic chemicals.acids,compounds of toxic metals such as lead (Pb)a, arsenic (As) and selenium (Se) andsalts such as NaCl in ocean water and fluorides (F) found in some soils.

Human sources (causes): Surface runoff, industrial effluents, and household cleaners.

Effects:

1. Can make fresh water unusable for drinking or irrigation.

2. Causes skin cancers and neck damage.

3. Damage the nervous system, liver and also kidneys.

4. Harm fish and other aquatic life.

5. Lower crop yields.

6. Accelerates corrosion of metals exposed to such water.

• Organic Chemicals

Examples: Oil, gasoline, plastics, pesticides, cleaning solvents, detergents.

Human sources (causes): Industrial effluents, household cleaners, surface runoff from farms.

Effects:

1. Can threaten human health by causing nervous system damage and some cancers.

2. Harm fish and wildlife.

3. Plant Nutrients

Example: Water-soluble compounds containing nitrate (NO3), phosphate (po4) and ammonium (NH4+) ions.

Effects:

1. Can cause excessive growth of algae and other aquatic plants which die, decay, deplete dissolved oxygen in the water and kill the fish and other aquatic lives.

2. Drinking water with excessive levels of nitrates lower the oxygen-carrying capacity of the blood and can kill urban children and infants.