Water Pollution: Global Impact And Statistics

Water pollution is a pressing global issue, with human activity being the primary cause. It occurs when hazardous chemicals and toxins contaminate water sources, degrading water quality and endangering human health and ecosystems. According to the World Health Organization (WHO), unsafe drinking water causes approximately 505,000 diarrhoeal deaths annually and is a major transmitter of diseases such as cholera, dysentery, typhoid, and polio. In 2022, 1.7 billion people relied on faecally contaminated drinking water sources, and over 2 billion people lived in water-stressed countries. Water pollution is caused by various factors, including industrial waste, agricultural runoff, plastic waste, and oil spills, with developing countries bearing a significant brunt of the impact.

Global access to safe drinking water

Water is a "'universal solvent", meaning it can dissolve more substances than any other liquid on Earth. This makes water highly vulnerable to pollution. Water pollution occurs when harmful substances, often chemicals or microorganisms, contaminate a body of water, degrading water quality and rendering it toxic to humans or the environment.

Unsafe water kills more people each year than war and all other forms of violence combined. Diarrhoea, which is largely preventable, is estimated to cause approximately 505,000 deaths each year, and the deaths of 395,000 children under 5 years of age could be avoided annually if risk factors were addressed. In addition, over 251 million people required preventative treatment for schistosomiasis in 2021, a disease caused by parasitic worms contracted through exposure to infested water.

In 2022, 6 billion people used safely managed drinking water services, leaving 2.2 billion people without. Of these 2.2 billion, 1.5 billion had basic services, 292 million had limited services, 296 million used unimproved sources, and 115 million collected untreated surface water from lakes, ponds, rivers, and streams. In 35 countries, less than half of the population used safely managed drinking water services in 2022. The burden of water collection disproportionately falls on women and girls, who are primarily responsible for domestic chores in many countries.

Access to safe drinking water is determined by the type and location of water sources, as well as the quality and availability of those sources. Safe and readily available water is important for public health, whether it is used for drinking, domestic use, food production, or recreational purposes. It can also boost countries' economic growth and contribute to poverty reduction.

Water pollution sources

Water pollution occurs when harmful substances contaminate a body of water, degrading water quality and rendering it toxic to humans or the environment. This widespread problem jeopardizes our health, with unsafe water killing more people each year than war and all other forms of violence combined.

There are two main types of water pollution sources: point source and non-point source (or diffuse) pollution. Point source pollution refers to contamination originating from a single source, such as wastewater discharged by a manufacturer, oil refinery, or wastewater treatment facility, as well as leaking septic systems, chemical and oil spills, and illegal dumping. Non-point source pollution, on the other hand, comes from widespread sources like nutrients, pesticides, and pollutants released by industry into the air, which eventually make their way back to land and water bodies.

One of the significant contributors to water pollution is the agricultural sector. Farming and livestock production consume about 70% of the earth's surface water supplies, and they are also a leading cause of water degradation. Agricultural activities contribute to the contamination of rivers, streams, wetlands, lakes, estuaries, and groundwater. Every time it rains, fertilizers, pesticides, and animal waste from farms wash nutrients and pathogens, including bacteria and viruses, into our waterways. Nutrient pollution, caused by excess nitrogen and phosphorus, is the top threat to water quality worldwide and can lead to harmful algal blooms.

Industrial activities also play a role in water pollution. Factories, power plants, and other manufacturing facilities release toxic chemicals, metals, solvents, and sludge into water bodies, either directly or through air pollution. In addition, the improper disposal of radioactive waste from nuclear energy facilities can have hazardous consequences for the environment. Oil pollution is another significant issue, with land-based sources like factories, farms, and cities contributing to the majority of oil in our seas.

Water pollution also arises from everyday human activities. For example, stormwater runoff occurs when rainfall washes road salts, oil, grease, chemicals, and debris from impermeable surfaces into waterways. Additionally, the improper disposal of chemicals and waste by individuals can lead to contamination.

Water pollution and health

Water pollution occurs when harmful substances contaminate a body of water, degrading water quality and rendering it toxic to humans or the environment. This widespread problem jeopardizes human health and safety. According to the World Health Organization (WHO), unsafe drinking water is a significant contributor to the millions of deaths that occur each year from diarrhoeal diseases, with children being particularly vulnerable.

The primary sources of water pollution include industrial activities, agricultural practices, and urban life. Industrial wastewater often contains toxic chemicals, heavy metals, and volatile organic compounds, which can have severe health consequences if ingested. For example, the contamination crisis in Flint, Michigan, due to lead-tainted water, resulted in various health issues, including skin rashes, respiratory infections, and even hepatitis. Similarly, pesticides and fertilizers used in agriculture can contaminate water sources, posing risks to both ecological and human health. Pesticides, for instance, have been linked to an increased medical disability index in older adults.

Water pollution also leads to eutrophication, where excessive nutrients, such as nitrogen and phosphorus, cause algal blooms that deplete oxygen levels in aquatic environments, creating "dead zones" devoid of life. These harmful algal blooms can produce neurotoxins that affect a variety of wildlife, including whales and sea turtles. Additionally, plastic pollution in oceans and other water bodies has a detrimental impact on marine life, disrupting ecosystems and threatening the health of animals that ingest or become entangled in plastic waste.

The impact of water pollution on human health is significant, and unsafe water kills more people each year than war and all other forms of violence combined. Globally, an estimated 80% of wastewater from human activities is discharged into water sources without proper treatment, leading to environmental pollution and the spread of diseases. According to WHO, in 2022, at least 1.7 billion people relied on drinking water sources contaminated with faeces, highlighting the urgency of addressing microbial contamination in drinking water.

Access to safe and readily available water is crucial for public health and can be achieved through improved water supply and sanitation, as well as better management of water resources. In 2022, 73% of the global population (approximately 6 billion people) had access to safely managed drinking water services, while the remaining 2.2 billion lacked such access.

Water pollution and the environment

Water pollution is the release of substances into bodies of water, making it unsafe for human use and disrupting aquatic ecosystems. Water pollution occurs when harmful substances, often chemicals or microorganisms, contaminate a body of water, degrading water quality and rendering it toxic to humans and the environment.

Water pollution is a significant global issue that affects both surface water and groundwater. Surface water pollution refers to the contamination of oceans, lakes, rivers, and other visible water sources, while groundwater pollution involves the contamination of water beneath the Earth's surface, often from metals and industrial production waste. According to the United Nations, more than 80% of the world's wastewater flows back into the environment without proper treatment, and this figure exceeds 95% in some least-developed countries.

The sources of water pollution are diverse and numerous. One significant contributor is agricultural activities, which include the use of fertilizers, pesticides, and animal waste. When it rains, these substances are washed into waterways, leading to nutrient pollution and toxic algal blooms that harm both people and wildlife. Industrial activities also play a role, with factories, farms, and cities contributing to water pollution through the release of toxic chemicals, oil, and other pollutants. In addition, the transportation and storage of oil are subject to leakage, and oil spills from tankers account for about 10% of the oil in waters worldwide.

Water pollution has far-reaching consequences for both the environment and human health. It destroys biodiversity, depletes aquatic ecosystems, and contaminates the food chain. Polluted water is also a major health hazard, causing diseases such as diarrhoea, cholera, dysentery, typhoid, and polio. According to the World Health Organization (WHO), polluted water is water that has become unusable due to changes in its composition, making it toxic and unsuitable for drinking or essential purposes like agriculture. Inadequate management of wastewater and the natural presence of chemicals in groundwater further compound the issue, with an estimated 1 million people dying annually from diarrhoea caused by unsafe drinking water, poor sanitation, and lack of hand hygiene.

The impact of water pollution extends beyond health and environmental concerns. Deteriorating water quality can stall economic growth and exacerbate poverty, as highlighted by the president of the World Bank, David Malpass. With less than 1% of the Earth's freshwater being accessible, the challenges posed by water pollution are expected to increase by 2050, when global demand for freshwater is projected to rise by a third. Therefore, addressing water pollution is crucial for ensuring sustainable access to safe and affordable drinking water, as outlined in the United Nations' Sustainable Development Goal target 6.1.

Water conservation and efficiency

Water is a universal solvent, which means it can dissolve more substances than any other liquid on Earth. This makes water highly vulnerable to pollution. Water pollution occurs when harmful substances, often chemicals or microorganisms, contaminate a water body and degrade water quality, making it toxic to humans and the environment.

Water efficiency measures can be implemented in various settings:

• Laundry: The most efficient way to wash clothes is with an ENERGY STAR-rated washing machine that adjusts the water level according to the load.
• Dishwashing: Using an ENERGY STAR-rated dishwasher that uses less than 5 gallons of water per load is the most efficient way to wash dishes. Alternatively, dishes can be washed by hand, minimizing the faucet's water flow.
• Toilets: Install high-efficiency WaterSense-labelled toilets or retrofit water-saving devices on existing ones. To conserve water, one can also adopt the practice of "letting it mellow" and not flushing after urinating.
• Showers: Low-flow showerheads help save water and should be preferred. Even with these showerheads, it is essential to minimize shower time.
• Diet: Reducing meat and dairy consumption helps conserve water as producing these foods is water-intensive.
• Appliances: As appliances and equipment age, replace them with water-saving models.
• Cooling: Minimize the water used in space cooling equipment, and shut off cooling units when not in use.

Frequently asked questions