Water Pollution's Rising Threat: A Historical Perspective

Water pollution has been an ongoing issue for centuries, with human activity contaminating sources of drinking water and causing diseases such as cholera and typhoid. Despite improvements in water quality in certain regions, such as the United States, due to legislation like the Clean Water Act, water pollution continues to increase globally. According to the United Nations, more than 80% of the world's wastewater is discharged back into the environment without adequate treatment, leading to unsafe water that poses health risks and claims more lives annually than war and violence. The primary sources of water pollution include industrial waste, agricultural runoff, improper waste disposal, and sewage contamination, threatening both human health and the environment.

Industrial waste

The introduction of new products, such as computers, drugs, plastics, and dyes, has also led to the creation of hazardous waste, including toxic chemicals that can have adverse effects on the environment and human health. High levels of toxic contaminants have been found in animals and humans, particularly those who are continually exposed to waste streams, such as farm and oil and gas workers.

Wastewater from manufacturing and chemical processes in industries is a significant contributor to water pollution. This is known as industrial wastewater or industrial wastewater pollution. It contains specific chemical compounds, with toxic wastes and organic pollutants being the most common forms. While most major industries have treatment facilities for industrial effluents, small-scale industries often cannot afford the necessary investments in pollution control equipment.

The illegal discharge of wastewater from industries into rivers and lakes is a global issue, with emerging countries such as China, India, and those in Africa and South America being particularly affected due to their rapidly growing industrial sectors and lack of consistent environmental policy implementation and monitoring.

In the United States, wastewater treatment facilities process about 34 billion gallons of wastewater per day, reducing pollutants such as heavy metals and toxic chemicals in industrial waste. However, aging and overwhelmed sewage treatment systems also release more than 850 billion gallons of untreated wastewater each year, contributing to water pollution.

Industrial water pollution has severe consequences for human health, wildlife, and the environment. It can make water unsuitable for drinking, recreation, agriculture, and industrial processes. It also diminishes the aesthetic quality of water bodies and can destroy aquatic life and reduce its reproductive abilities.

Some specific examples of industrial waste polluting water sources include:

• Anaconda Aluminum in Montana, which contaminated local water sources with lead and chromium.
• Gulf States Utilities in Louisiana, which discharged toxins into marshlands, polluting waters with benzene and other chemicals.
• Conklin Dumps in New York, which leaked volatile organic chemicals into the groundwater.
• In North Carolina, coal-fired power plants have resulted in elevated levels of chromium-6 and other chemicals in the water, forcing nearly 1,000 households to rely on bottled water for daily tasks.
• In Albany, Georgia, three separate areas of groundwater are polluted with cyanide and chloroform from various industries, with one contaminated area originating from a landfill on the Marine Corps' Logistics Base.

Sewage systems

The problem of sewage pollution is multifaceted and varies across different regions. In the United States, ageing infrastructure, including pipes that are nearly 200 years old, is a significant factor. Poor urban planning exacerbates the issue, as urban sprawl increases the amount of stormwater flowing into sewers and the subsequent pollution discharged. Additionally, sewage systems in the United States combine stormwater with household sewage, leading to further contamination.

Similarly, in the United Kingdom, sewage pollution has gained significant attention due to the government's initial refusal to mandate water companies to ensure untreated sewage is not discharged into rivers. While the government argued that the necessary improvements would cost taxpayers hundreds of billions of pounds, they eventually agreed to introduce changes following public backlash and campaigns. The UK's sewer system is struggling to cope with increased sewage flow due to decades of underfunding, deregulation, inadequate monitoring, and profit prioritisation.

The impact of sewage pollution extends beyond just human health hazards, as it also poses a significant threat to natural ecosystems. Sewage released into rivers contains high levels of nitrogen and phosphorus, stimulating the growth of algae and leading to algal blooms. These blooms block light necessary for plant photosynthesis, and when the plants and algae begin to decay, they are consumed by bacteria, reducing oxygen levels in the water and causing the death of fish and other organisms.

The issue of sewage pollution demands urgent attention and collaboration between various sectors. While new sewage management solutions are emerging, such as waste-free toilets and resource recovery, more innovation and investment are needed to address this global crisis.

Oil pollution

Furthermore, land-based sources, such as factories, farms, and cities, are responsible for nearly half of the estimated 1 million tons of oil that enters marine environments annually. Natural seepage from the ocean floor, through fractures called seeps, also contributes to oil pollution. Oil pollution has increased in certain regions, such as the Vishakhapatnam coast in India, where oil transport has intensified over the past decade, raising the risk of potential spills.

The impact of oil spills can be long-lasting and detrimental. Even after an oil spill has been seemingly cleaned up, oil can continue to seep from the spill site, causing ongoing degradation of vegetation and ecosystems. Studies have shown that the chronic occurrence of minor spills can have greater detrimental effects than the more visible large-scale spillages. Oil spills can also have immediate and direct health impacts on those involved in fishing and cleanup efforts, including headaches, nausea, breathing difficulties, and eye and throat irritation.

While there have been improvements in technology and coordinated responses to oil spills, there is still no thoroughly satisfactory method for cleaning up major spills. Current response strategies focus on containing and removing the oil to allow for the resumption of economic activity and the natural recovery of the marine environment. However, the use of high-pressure, hot-water hoses for cleanup can sometimes cause more damage than the oil itself, and the long-term effects of oil spills on cancer and other chronic diseases remain understudied.

Radioactive waste

The impact of radioactive contamination on marine life and humans is still unclear. While signs indicate that nuclear isotopes are moving up the local food chain, the mass dumping of nuclear material by the Soviets in the Arctic has not definitively shown to have caused widespread harm to marine life. This may be due to containment vessels around some of the dumped reactors preventing the escape of radiation. However, incidents such as the die-off of seals in the Barents Sea and White Sea from blood cancer and the deaths of millions of starfish, shellfish, seals, and porpoises in the White Sea have been attributed by Russian scientists to pollution or nuclear contamination.

Agricultural pollution

Agriculture is a leading cause of water pollution. Over the last 100 years, agricultural expansion and intensification have led to changes in water quality and the health of stream ecosystems. The global market in pesticides is worth more than USD 35 billion per year, and some countries, such as Argentina, Malaysia, South Africa, and Pakistan, have experienced double-digit growth in the intensity of pesticide use.

Agricultural runoff is a significant contributor to water pollution. This includes fertilizer and manure runoff, which can stimulate algal blooms in lakes and rivers, leading to hypoxic (low oxygen) conditions that are harmful to aquatic life. Algal blooms can also affect the recreational use of local streams, downstream reservoirs, and estuaries, and block sunlight, disrupting the ecosystem below the water surface. In addition, excessive sedimentation from erosion can overwhelm aquatic ecosystems, smother breeding areas, and degrade coastal and marine ecosystems, including coral reefs.

Pesticide runoff poses risks to aquatic life, fish-eating wildlife, and drinking water supplies. It can also be harmful to human health, with farmworkers and rural residents particularly susceptible to exposure. Pesticides have also been linked to the decline in insect populations, such as the monarch butterfly and native bees.

Livestock production accounts for 70% of all agricultural land and 30% of the planet's land surface. Livestock and poultry manure can pollute waterways, with chicken manure being especially prone to causing phosphorus runoff. Manure management accounts for a significant proportion of agricultural greenhouse gas emissions and contributes to air pollution through the emission of ammonia and other pollutants.

Aquaculture has grown more than 20-fold since the 1980s, particularly in Asia, and fish excreta and uneaten feeds from fed aquaculture can diminish water quality. The increased use of antibiotics, fungicides, and anti-fouling agents in aquaculture may contribute to polluting downstream ecosystems.

To address agricultural water pollution, various practices and policies can be implemented. These include nutrient management practices, such as targeted fertilizer and manure application, drip irrigation, and storing livestock manure in protected areas to minimize runoff risks. Conservation practices, such as contour strip cropping, can also help reduce erosion and runoff. Additionally, a combination of regulations, economic incentives, and information can be used to encourage more sustainable practices and diets.

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