1
Introduction to Water Pollution

Hira Munir1*, Areeba Kashaf1, Mahnoor Masood1, Rabia Sajid1, Hira Amjad1, Tahreem Shehzadi1 and Jawayria Najeeb2

1Department of Biochemistry, Government College Women University Faisalabad, Faisalabad, Pakistan

2Department of Chemistry, University of Gujrat, Gujrat, Pakistan

Abstract

Contamination in natural resources is principally pollution; water pollution is one of them. Natural water is pure and useable but nowadays it is polluted due to human activities. When different contaminants enter water bodies like rivers, lakes and oceans, they make the water unsafe for human consumption and also disturb the aquatic ecosystem. Water pollution from a point source or non-point sources has drastic effects on marine life and human health. Due to urbanization, industrialization increased. Industries, without treating that chemical-containing water, release effluents into water bodies. Later on, chemicals like arsenic, phosphorous and other pesticides will cause severe toxicity for aquatic life and also cause kidney and liver disorders in humans. Color, pH, turbidity, hardness, BOD, and TDS exist as constraints to water quality. Water pollution can be reduced by management or by applying strategies like water maintenance, reducing plastic pollution, controlling air pollution and educating people about environmental preservation. Before releasing any industrial waste, it is essential to treat that contaminated water. By using biotechnological approaches, we can prevent water pollution on a higher level.

Keywords: Water, contamination, pollution, agriculture, biotechnology, plastic wastes, microorganisms, sewage, industry

1.1 Pollution

Pollution can be defined as a flow of physical constituents that harm the human ability or capacity to adore life. Pollution includes running down any resource faster than it can revive itself, physical garbage, air and water pollution, exhaustion of the soil, problems of dichloro-diphenyl-trichloroethane (DDT), noise and radiation levels [1]. The by-product of production is contamination, which is steadily dissolving and damaging the environment. The adverse effects of pollution are ignored by the market outcome and therefore result in greater levels of output and pollution as well [2]. Pollution is a diverse term; it is a form of unwanted energy that is detrimental to well-being [3].

1.2 What is Water Pollution?

In the 21st century, one of the major difficulties that humanity is facing is associated with water quality issues. In all parts of the world, organic toxic waste of water has become the foremost community distress. The unhygienic and poor quality of water is responsible for about 3.1% of deaths worldwide [4]. Due to climate change, there is an escalation of the water cycle; high temperature of water and melting of glaciers are causing water problems to be more serious. Agricultural, domestic and industrial sectors consume more than 1/3rd of water on Earth and these actions are the basis of water impurity. Recreation, urbanization, population growth and exposure to pathogens through food chains are additional threats [5]. Among the natural resources water is the most vigorous component as it is essential for the survival of life, production of food, and economic growth. Seawater is 98% water; high salt concentration makes it unusable while freshwater is only 2% percent and 1.6% is covered by glaciers and ice sheets. Another 0.36% exists as groundwater and water boreholes and 0.036% could be reachable to ponds and channels [6]. Environment and progress are highly affected by the quality (depending upon region and season) and accessibility of water. Worldwide many cities are facing severe water shortages. Water contamination is a stern risk to both the Earth and its inhabitants [7].

The word "pollute" means to make something infected or unclean. In the case of water, pollution infers observable floating debris is present [8]. A water pollutant is the accumulation of any material to water that alters its usual characteristics to such a degree that it can be used or whatever thing which brings about a decline in the diversity of aquatic life and ultimately disturbs the balance of life [9]. About 80% of the population is showing higher levels of hazards related to water [10]. Living beings require pure, safe water to grow. Water is the universal solvent and hence a major cause of infections worldwide. Waterborne diseases are 80% as stated by WHO. In most countries, potable water does not reach WHO standards [11].

Outflow from water tanks and discharge of domestic and industrial waste, marine discarding, radioactive waste and atmospheric deposition cause water pollution. There is an addition of trash metals in ponds and rivers that are harmful to living beings. The toxins cause immune destruction, regenerative collapse and critical toxicity. This includes communicable infections such as bacterial dysentery, typhoid, gastrointestinal diseases, skin and renal problems [12]. Plants and animal nutrition directly affect human health. Water pollutants are slaughtering marine life, which reduces foodstuff meant for humans. Insecticide absorption is growing in the food chain and is damaging to people [13].

Domestic sewage (Figure 1.1) causes 75-80% of water pollution. There are fewer flora and fauna in the polluted river that has unbearable smells [14]. Numerous marine ecologies (lakes, salted water and marine water) are at risk of indirect outcomes for mortality. Ineffectively handled or unprocessed water is released in large quantities into surface, earth and coastline water [15].

Figure 1.1 Domestic sewage.

1.3 Prevalence of Water Pollution

According to WHO reports, approximately one thousand million people drink water from a source polluted with faeces worldwide, which causes infectious diseases such as cerebral palsy, fever, dehydration, intestinal infection, and hepatitis. Hence, twelve lac individuals are dying from water-borne infections yearly. In underdeveloped and developing countries, almost 50% of the inhabitants have water-related issues. Table 1.1 presents the frequency (%) of water toxic waste in different countries. Contaminants, for example micro-plastics, anti-bacterial medicines, PFAS and many other related products in water, are health hazardous to organisms. Water is essential for drinking and sanitation, farming, businesses and industry [15].

Out of 122 nations, Pakistan ranks at number 80 concerning water quality. Coliforms, toxic metals and pesticides cause water contamination throughout the country. Water quality parameters set by WHO are often violated [12].

Arsenic-containing potable water is affecting sixty million Pakistanis, the largest mass poisoning in history. In the dried pipes used for water supply, an E. coli bacterium can grow into masses within a week. Intake of such polluted water may cause bone and false teeth damage, diarrhea, fever, liver damage, other waterborne infections and death of numerous people [16].

1.4 Categories of Water Pollution

There are two categories of water pollution:

• Point sources
• Non-point sources

Table 1.1 Frequency (%) of polluted water in different countries.

1.4.1 Point Sources

Point sources are the category of water pollution directly from an identifiable source. This includes the following:

• Wastewater effluent
• Stormwater discharge

All of this affects the area near these point sources. The characteristics of point sources of chemical inputs to receiving water are:

• Water effluent from municipal and industrial areas.
• Waste disposal site runoff and leachate.
• Animal feedlot runoff and infiltration.
• Mines, oil fields and unsewered industrial sites runoff.
• Storm sewer outfalls in cities with a population greater than 100,000.
• Sanitary and combine storm outfalls.
• Construction site runoffs [17].

Point source pollution is always from a known source such as the industry of sewage pipelines. These sources are associated with manufacturing processes and their discharge from water treatment plants and animal feeding operations [18]. Industries dump toxic chemicals into the waterways as shown in Figure 1.2, sometimes intentionally or sometimes accidentally. These pollutants reduce oxygen from the water body which will kill aquatic life. They may settle in the tissues of fishes which we will eat. All this pollution affects forest trees and agricultural fields when this water reaches them. Point source pollution is artificial pollution; it is basically from domestic, industrial and farm stocking residue sources [19].

Figure 1.2 Toxic industrial waste.

1.4.2 Non-Point Sources

It is the category of water pollution which gathers from different origins from different non-identifiable...