The Pros And Cons Of Pollutio Pollution

2.1 WATER

Water is one of the most common substances on the Earth. It is the main constituent of oceans, streams and lakes as it covered over almost 70% of the surface of the Earth. It can exist naturally in three physical states which is in form of gas, liquid and solid. The chemical formula for water is H2O as it contains oxygen and hydrogen atoms which are linked by covalent bond (Shakashiri, 2011). Clean water is essential in life as it is the source for drinking, food preparation, to water plants and sanitation. Without water, humans, animals and plants will become dehydrated and could lead to death.

Nowadays, living creatures are struggling to get fresh and clean water as there is only 2.5 percent of total water in this world is fresh (NG, 2015). Then, according to Davis (2010), large amount of freshwater is trapped in glaciers and snowfields and almost only 1 percent is accessible. He added, only 0.007 percent of this Earth's water is available to fuel and feed 7.5 billion people and it is insufficient. Thus, this world need more clean water to make sure all living things can get enough of nutrients and could avoid disease such as diarrhoea (Howard, 2003) which is caused by unsafe water.

2.2 WATER POLLUTION

Nowadays, there are many pollution issues that are reported especially related to water pollution. According to Dozier (2005), pollution is refer to something that is added into the environment thus make it unclean and unsafe for living things to consume. He also mentioned that water pollution is occurred when the aquatic organisms cannot keep up with their cleaning roles as the water becomes excessive with too much of impurities and dirty things. Based on Mann, Dhingra & Singh (2014) research, they agreed that water pollution occurred when pollutants are being released direct or indirectly into the bodies of water without taking any proper treatments in order to discard the harmful