Water Pollution
Water pollution can be defined as the contamination of water bodies. Water pollution is caused
when water bodies such as rivers, lakes, oceans, groundwater and aquifers get contaminated with
industrial and agricultural effluents.
When water gets polluted, it adversely affects all lifeforms that directly or indirectly depend on
this source. The effects of water contamination can be felt for years to come.
Various Causes of Water Pollution
1. Industrial waste
Industries produce a huge amount of waste which contains toxic chemicals and pollutants which
can cause air pollution and damage to us and our environment. They contain pollutants such as
lead, mercury, sulfur, asbestos, nitrates, and many other harmful chemicals. Many industries do
not have a proper waste management system and drain the waste in the fresh water which goes
into rivers, canals and later into the sea. The toxic chemicals have the capability to change the
color of water, increase the number of minerals, also known as eutrophication, change the
temperature of water and pose a serious hazard to water organisms.
2. Sewage and wastewater
The sewage and wastewater that is produced by each household is chemically treated and released
into the sea with fresh water. The sewage water carries harmful bacteria and chemicals that can
cause serious health problems. Pathogens are known as a common water pollutant; The sewers of
cities house several pathogens and thereby diseases.
3. Mining activities
Mining is the process of crushing the rock and extracting coal and other minerals from
underground. These elements when extracted in the raw form contains harmful chemicals and can
increase the number of toxic elements when mixed up with water which may result in health
problems. Mining activities emit a large amount of metal waste and sulphides from the rocks which
is harmful to the water.
4. Marine dumping
The garbage produced by each household in the form of paper, aluminum, rubber, glass, plastic,
food is collected and deposited into the sea in some countries. These items take from 2 weeks to
200 years to decompose. When such items enter the sea, they not only cause water pollution but
also harm animals in the sea.
5. Accidental oil leakage
Oil spill poses a huge concern as a large amount of oil enters into the sea and does not dissolve
with water; thereby opens problem for local marine wildlife such as fish, birds and sea otters. For
e.g.: a ship carrying a large quantity of oil may spill oil if met with an accident and can cause
varying damage to species in the ocean depending on the quantity of oil spill, size of the ocean,
the toxicity of pollutant.
6. The burning of fossil fuels
Fossil fuels like coal and oil when burnt produce a substantial amount of ash in the atmosphere.
The particles which contain toxic chemicals when mixed with water vapor result in acid rain. Also,
carbon dioxide is released from the burning of fossil fuels which result in global warming.
7. Chemical fertilizers and pesticides
Chemical fertilizers and pesticides are used by farmers to protect crops from insects and bacteria.
They are useful for the plant’s growth. However, when these chemicals are mixed up with water
produce harmful for plants and animals. Also, when it rains, the chemicals mix up with rainwater
and flow down into rivers and canals which pose serious damages for aquatic animals.
8. Animal waste
The waste produced by animals is washed away into the rivers when it rains. It gets mixed up with
other harmful chemicals and causes various water-borne diseases like cholera, diarrhea, jaundice,
dysentery and typhoid.
EFFECTS OF WATER POLLUTION
Pollution of water affects both humans and aquatic life. Most water sources close to cities and
urban centres are polluted by garbage and dumping of chemicals, legally or illegally. Below are
some of the common as well as adverse effects of polluting water bodies.
Effects on Human Beings:
Life is a cycle, and humanity’s irresponsible behaviour often comes back to haunt it. Adding
contaminants to water bodies has affected the human family in several ways. According to a 2017
WHO report, 2.1 billion people do not have access to safe water. In 2019, it stated that 785 million
people lack access to essential drinking water. One of the main effects of this is diseases. World
Health Organisation notes that there are about 120,000 cholera-related deaths annually. Also, the
Fukushima tragedy, for example, increased the prevalence of thyroid cancer in exposed infants by
70%.
2. Death of Aquatic Life
Animals and plants that depend on water for life are the most affected by polluted water. Statistics
from the Centre for Biological Diversity on the effects of the Deep Horizon spill provides a useful
glimpse of the impact of pollution on aquatic life.
