Polluted Water: A Slow Poison For People's Health

Water pollution is a critical issue that poses a significant threat to human health and ecosystems. It occurs when harmful substances contaminate bodies of water, making them unsafe for human use and disrupting aquatic life. The contamination of water sources can have far-reaching consequences, from gastrointestinal issues to long-term health effects such as cancer and neurological disorders.

Water pollution can be caused by various human activities, including industrial waste, improper farming practices, and inadequate sewage treatment. These activities introduce toxic chemicals, heavy metals, and pathogens into water sources, leading to a range of health issues. For example, nitrates from fertilizers can enter drinking water, posing serious health risks to infants.

Additionally, water pollution disrupts aquatic ecosystems, leading to a decline in biodiversity and the destruction of habitats. It also has economic implications, affecting industries such as fishing, tourism, and agriculture.

Addressing water pollution requires a multifaceted approach, including individual actions, government regulations, and technological innovations, to mitigate its harmful effects and protect both human health and the environment.

Drinking Contaminated Water

Diarrhoea and Gastrointestinal Issues

One of the most common health issues associated with drinking contaminated water is diarrhoea. Diarrhoeal diseases are a leading cause of illness and death, especially in young children and individuals in low-income countries. Contaminated water often contains disease-causing microorganisms, such as enteroviruses, which are transmitted through groundwater, rivers, seawater, sewage, and drinking water. Improperly treated or untreated water has been linked to a higher risk of diarrhoea.

Cholera

Cholera is another waterborne disease that can be contracted through contaminated drinking water. It is caused by consuming water contaminated with Vibrio cholerae bacteria, which is often found in water sources contaminated by sewage.

Dysentery

Dysentery is an inflammatory disorder of the intestine, often caused by bacterial or parasitic infections. It can be contracted by drinking water contaminated with bacteria or parasites, such as shigella or entamoeba histolytica.

Typhoid

Typhoid fever is a bacterial infection that can be spread through contaminated food or water. Drinking water contaminated with Salmonella typhi bacteria can lead to typhoid fever, which is characterised by fever, abdominal pain, and diarrhoea.

Hepatitis A

Hepatitis A is a liver infection caused by the hepatitis A virus (HAV). It is usually transmitted through contaminated food or water. Consuming water contaminated with HAV can lead to symptoms such as fever, fatigue, loss of appetite, nausea, and abdominal discomfort.

Poliomyelitis

Poliomyelitis, commonly known as polio, is a highly infectious disease caused by a virus that invades the nervous system. It can be spread through contaminated food or water. Drinking water contaminated with the poliovirus can lead to paralysis and other serious health issues.

In addition to these specific diseases, drinking contaminated water can also lead to more general health issues, such as altered brain function, damage to the immune and reproductive systems, and cardiovascular and kidney problems. It is important to note that the health effects of drinking contaminated water can vary depending on individual factors such as age, gender, and overall health status.

Direct Exposure to Toxic Algae

Direct exposure to toxic blue-green algae can cause a range of health issues in humans. Blue-green algae, or cyanobacteria, are naturally present in lakes and streams and typically become abundant in warm, shallow, undisturbed, nutrient-rich surface waters that receive a lot of sunlight. Under these conditions, blue-green algae can form blooms that discolour the water or produce floating mats or scums on the water's surface.

Exposure to blue-green algae blooms can cause health issues in people and animals when the contaminated water is touched, swallowed, or when airborne droplets are inhaled. High levels of exposure can cause:

• Diarrhea
• Nausea or vomiting
• Skin, eye, or throat irritation
• Allergic reactions or breathing difficulties

In addition, drinking water with high levels of blue-green algal toxins has been linked to liver and nervous system issues in laboratory animals, pets, livestock, and people. Some evidence suggests that long-term consumption of untreated surface waters containing high levels of blue-green algal toxins could increase the risk of liver cancer. However, this evidence is limited as the individuals in these studies were also exposed to other factors associated with liver cancer.

To avoid exposure to blue-green algae, it is recommended to:

• Avoid swimming or water sports where the water is discoloured or has visible scums.
• Avoid drinking untreated surface water, even if it has been treated with water filtration, chlorine, or ultraviolet (UV) light.
• Follow local warnings and advice regarding harmful algal blooms.

Ingesting Microplastics

Microplastics are a serious threat to human health and the environment. Microplastics are plastic particles smaller than 5mm in size, which are often formed when larger plastic materials are fragmented. They are easily ingested due to their size, and can move through the food chain, persisting in the environment as they are resistant to biodegradation.

Microplastics are found in the oceans, remote islands, and polar regions, and are now so widespread that they have been detected in drinking water and food sources around the world. A 2020 study estimated that humans ingest between 0.1 and 5 grams of microplastics weekly.

The effects of ingesting microplastics are not yet fully understood, but studies have shown that they can cause oxidative stress, inflammatory reactions, and metabolic disorders in humans. They can also carry other toxic chemicals, such as heavy metals and organic pollutants, which can further harm the human body.

The largest source of microplastics in the human diet is drinking water. A 2018 study found plastic particles in 93% of bottled water samples, and another study found 83% of tap water samples from around the world contained microplastics. Microplastics have also been found in marine life, beer, wine, rice, table salts, honey, fruits, and vegetables.

To reduce exposure to microplastics, it is recommended to avoid foods packaged in plastic and to use reusable totes and produce bags instead of plastic options. It is also advised to use loose-leaf tea instead of tea bags and to bring your own water bottle to reduce the consumption of bottled water.

Waterborne Diseases

• Cholera: This bacterial infection causes severe diarrhea and dehydration, which can be life-threatening if left untreated. It is often spread through contaminated water sources.
• Typhoid: Typhoid fever is caused by the Salmonella typhi bacterium, typically transmitted through contaminated food or water. It leads to high fever, stomach pain, and diarrhea.
• Dysentery: Dysentery is an inflammation of the intestines, usually caused by bacterial or parasitic infections from contaminated food or water. It results in diarrhea containing blood or mucus, abdominal pain, and fever.
• Hepatitis A: Hepatitis A is a viral infection that affects the liver. It is transmitted through contaminated food or water and causes jaundice, fatigue, abdominal discomfort, and nausea.
• Diarrhea: Diarrhea is a common symptom of gastrointestinal infections, often caused by consuming water contaminated with viruses or bacteria. It can lead to dehydration and electrolyte imbalances, especially in young children and vulnerable adults.

To prevent waterborne diseases, it is crucial to ensure access to clean and safe drinking water, proper sanitation, and hygiene practices. This includes treating wastewater, improving water infrastructure, and promoting education on safe water handling and consumption.

Eutrophication

One of the primary effects of eutrophication is the proliferation of algae, known as algal blooms. While algae are a natural part of aquatic ecosystems, too much nitrogen and phosphorus can cause algae to grow faster than the ecosystem can handle. These algal blooms can block sunlight from reaching underwater plants and harm water quality. As the blooms eventually die off, they are decomposed by bacteria, which consumes oxygen in the water and creates "dead zones" where most aquatic life cannot survive. This process is known as hypoxia and has been observed in many freshwater lakes and coastal marine environments.

In addition to health risks, eutrophication has economic implications. The cost of treating nutrient-polluted drinking water sources can be significant, and eutrophication can also impact tourism, property values, commercial fishing, and recreational businesses.

Frequently asked questions