Causes and Effects of Water Pollution

Causes and Effects of Water Pollution

Water pollution has become a major environmental concern for a number of reasons, with some issues being more serious and urgent than others. As human population grows, industrial and agricultural activities continue to expand, creating more sewage wastes and disposals. In order to address the problems caused by water pollution around the world, it is important to analyze the causes of water pollutants in both developed and developing countries.

1. Sources of Water Pollution in both Developed and Developing Countries

Clean and accessible water is important to human health and development. Yet over 884 million people of the global population does not access to sufficient and safe water supplies. In many developing countries, over 263 million people (mostly women) spend over 30 minutes per trip collecting water from distant, often polluted sources.^[1] These pollutants often gain access to the water supply through agriculture, industries, human sewage and rainwater runoff.

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• Agricultural Pollutants

Agriculture, which accounts for a total 70% of the global freshwater abstractions, plays a major role in in water pollution (Figure1).^[2] Agricultural water is used for irrigation to grow fresh produce and livestock. In many developed and emerging economic regions, agricultural pollutants are majorly due to the intensive use of pesticides, chemical fertilizers (such as nitrates and phosphates), fungicides, herbicides, or insecticides, as well as livestock excrement running off the water supply. For example, China, the world’s largest population, consumed itself about a third of the global fertilizers used for faster growth of fruit and vegetable production.^[3] In the United States, there is nearly 330 million acres of land used for agriculture^[4] that produce a large number of products and livestock for over a population of 325 million people.^[5] With the immediate pressure to meet an increasing food demand, many farmers in both developed and developing countries are expanding their cropping land activities to satisfy the growing population, along with many changes in their dietary patterns. Once being used excessively, these chemicals fertilizers are carried out by heavy rain into streams, groundwaters and lakes, threatening human health and destroying the ecosystem.

• Industrial Pollutants

Over the last few decades, many developing countries have loosened their environmental regulations in order to lure foreign investment into their territory. However, when moving their production overseas, these foreign companies have also offshored their heavy pollution to the host countries. Manufacturing facilities produce a lot of waste containing toxic pollutants. They then use 3% of the global freshwater to drain their wastes in the fresh water, which then flows into canals, rivers, and eventually in the oceans (Figure1). This point source pollution often includes non-biodegradable industrial wastes including lead, mercury, and industrial oils, that end up forming a thick sludge in the water, which are harmful to both maritime life and human health.

The Yamuna River of India, for example, which provides the city of New Delhi most of its drinking water, is considered dead zone due to the low oxygen level to support the fish existence.^[6] This polluted water also reaches and polluted groundwaters in India causing tremendous adverse effect on the health of the people. In Russia, a town in the name of Dzershinsk is considered as “the most chemically polluted town” in the world, due to many secret manufacturing sites that were once used to host several highly-polluting products during the great war^[7]. Even after most of these factories were shut down, few of them continue to hire over a quarter of local residents. Heavy metals, phenol, arsenic, dioxins, and other toxins can still be found in both groundwaters near the capital (Moscow) and in the White Sea, putting the life of over 700 species in jeopardy. ^[8]