Water Pollution: Understanding The Causes And Impacts

Water pollution is a critical issue that poses a significant risk to both human health and the environment. It occurs when toxic substances, such as chemicals, waste, plastic, and oil, contaminate water bodies like lakes, rivers, and oceans. This contamination can result from various sources, including industrial waste, agricultural runoff, sewage discharge, and accidental spills. The impact of water pollution extends beyond the degradation of water quality; it also disrupts aquatic ecosystems, infiltrates groundwater sources, and ultimately reaches our households as contaminated water. With the majority of the world's wastewater returning to the environment untreated, water pollution has become a pressing concern that demands our collective attention and action.

Oil spills and leaks

Oil on the surface of water blocks sunlight and reduces dissolved oxygen levels, harming aquatic life. It can ruin the insulating properties of feathers and fur, causing hypothermia in birds and marine mammals. Ingesting oil is toxic to animals and can damage their habitats, slowing the recovery of animal populations. Oil spills also impact plant life, such as saltwater marshes and mangroves.

Oil spills on land can penetrate underground and reach groundwater, affecting water sources that humans and other species rely on for survival. Runoff from asphalt and other sources can carry oil into waterways, and spills in industrial or domestic settings can enter water sources through storm drains.

The containment and cleanup of oil spills are challenging and costly, often running into millions or billions of dollars. While technology and coordinated response management have improved, there is still no thoroughly satisfactory method for cleaning up major spills. Efforts focus on containing and removing as much oil as possible to allow for economic activity resumption and natural recovery processes to take over.

To address oil spills, various regulations have been implemented, such as the Oil Pollution Act of 1990 in the US, which holds responsible parties accountable for cleanup and restoration. The International Spill Control Organization (ISCO), a nonprofit NGO, also aids in cleanup and promotes cooperation and preparedness worldwide.

Industrial waste

The effects of water pollution from industrial waste are devastating to people, animals, fish, and birds. Polluted water is unsuitable for drinking, recreation, agriculture, and industry. It diminishes the aesthetic quality of lakes and rivers, destroys aquatic life, and reduces reproductive ability. It can also cause waterborne diseases such as diarrhoea, giardiasis, typhoid, cholera, hepatitis, jaundice, and cancer.

In the United States, industrial practices have contaminated the drinking water of more than 244 million people, according to a News21 analysis of EPA data. Mining and smelting operations are responsible for contaminating water with heavy metals in almost every state. In addition, hundreds of companies have been contaminating drinking water for decades with arsenic, lead, mercury, and chromium, according to EPA data.

To address the environmental and health issues created by industrial wastewater, it is necessary to treat it with physical, chemical, and biological means so that it can be recycled for water conservation. The escalating population has resulted in a higher demand for water, which has led to rapid industrialization and increased waste. As a result, the proper treatment of wastewater before releasing it into water bodies has become essential to maximize the quality and quantity of potable water.

Sewage

The release of untreated sewage into water bodies has severe consequences for both human health and the environment. According to the Centers for Disease Control (CDC), between 1985 and 2000, there were 251 separate disease outbreaks and nearly half a million cases of waterborne illness from polluted drinking water in the United States. Waterborne pathogens, including bacteria and viruses from human and animal waste, are a major cause of these illnesses. Diseases spread by contaminated water include cholera, giardia, typhoid, and Legionnaires' disease.

In addition to the health risks, sewage pollution can also have detrimental effects on aquatic ecosystems. For example, sewage can cause algal blooms, which can lead to the deaths of many species. It can also attract fish due to the increased water temperature caused by wastewater outflows, leading them into an "ecological trap" where contaminants are at their highest. This can result in the decline or elimination of certain species, as seen in the case of mayflies in the River Way in 2014.

While the responsibility for treating sewage lies with utility companies, individuals can also play a role in improving water quality. This includes properly maintaining septic systems and supporting initiatives to reduce sewage pollution, such as federal and state right-to-know policies that inform citizens about sewage contamination in their waterways.

Agricultural practices

Agriculture is a major cause of water pollution, and the impact of agricultural practices on water quality is a significant concern. It is considered the largest contributor of non-point-source pollution to surface water and groundwater worldwide.

Fertilizers and manure contribute to increased levels of nitrogen and phosphorus in water bodies, leading to eutrophication and the development of hypoxic conditions that are harmful to aquatic life. This process, known as eutrophication, is caused by the destructive overgrowth of algae, which can also affect the recreational use of local streams, downstream reservoirs, and estuaries. Fertilizer runoff is a significant source of pollution, particularly in rivers and streams, and can lead to the creation of "dead zones" where marine life is devastated, as seen in the Gulf of Mexico.

Additionally, agricultural practices can result in sedimentation, which occurs when soil erosion releases excess sediment into water bodies. This can overwhelm aquatic ecosystems, smother breeding areas, and degrade coastal and marine ecosystems, including coral reefs.

The use of antibiotics in agriculture is another emerging issue. Veterinary medicines, including antibiotics, vaccines, and growth promoters, can move from farms through water to ecosystems and drinking water sources, potentially impacting human health.

Poorly planned and executed agricultural practices, such as those seen in the Aral Sea basin, can lead to social, economic, and ecological disasters. The intensification of farming practices, including the increased use of fertilizers, has resulted in higher nitrogen levels in groundwater in many parts of the world. This has direct and indirect impacts on human health, with excessive nitrate levels in drinking water being a particular concern.

However, it is important to recognize that agriculture is not just a contributor to water pollution but also a victim of it. The use of wastewater and polluted surface and groundwater can contaminate crops, transmit diseases to consumers and farmworkers, and impact the quality of agricultural products.

Radioactive waste

Radioactive contamination can occur due to the release of radioactive gases, liquids, or particles. For example, if a radionuclide used in nuclear medicine is spilled, the material could be spread by people as they walk around. Radioactive contamination may also be an inevitable result of certain processes, such as nuclear fuel reprocessing. In cases where radioactive material cannot be contained, it may be diluted to safe concentrations.

There have been several instances of radioactive contamination causing water pollution. Since 1952, low levels of radioactive waste have been discharged into the Irish Sea, the English Channel, and the Arctic Ocean. In 2011, an earthquake and tsunami in Japan caused major damage to the Fukushima Daiichi nuclear power plant, resulting in the release of thousands of tons of radioactive water into the Pacific Ocean. Radioactive caesium and plutonium were found in seals and porpoises in the Irish Sea, indicating that radiation can enter the food chain through plankton and kelp and then contaminate fish.

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