Water pollution occurs when water becomes contaminated, usually by chemicals or microorganisms. Pollution can cause water to become toxic to humans, leading to infections and health problems.
Water is an essential resource for all life on Earth. If a water source becomes contaminated due to pollution, it can lead to health issues in humans, such as cancer or cardiovascular conditions.
This article explores the causes of water pollution, how it can affect human health, and what people can do to help prevent it.
Water is a natural resource that all living creatures require. Clean water is also used in manufacturing and for social and economic development.
However, according to the United Nations (UN), 2.2 billion people lacked access to safely managed drinking water services in 2022.
The
- Over 2 billion people live in countries with high levels of water stress, meaning the amount of water available is less than the amount required.
- Around 700 million people do not have basic drinking water services.
- Water pollution is worsening at all stages of the water cycle.
Water is sometimes referred to as the universal solvent, as it dissolves more substances than any other liquid. However, this ability means that water is easily prone to pollution.
Below are just some of the many ways that water pollution can occur.
Sewage and wastewater
After being used, water becomes wastewater. Wastewater can be domestic, such as water from toilets, sinks, or showers, or from commercial, agricultural, or industrial use. Wastewater also refers to rainwater that washes oil, grease, road salt, debris, or chemicals from the ground into waterways.
Agriculture
The agriculture industry is one of the biggest consumers of fresh water. In fact, around 70% of the world’s freshwater use goes toward crop agricultural irrigation. In some countries, this figure is considerably higher. For example, in Pakistan, around 98% of freshwater goes toward agricultural use.
One way that agriculture causes water pollution is through rainwater. When it rains, pollutants such as fertilizers, animal waste, and pesticides wash from farms into waterways, contaminating the water.
Contaminates from agriculture usually contain high amounts of phosphorous and nitrogen, which encourage the growth of algal blooms. These blooms produce toxins that kill fish, seabirds, and marine mammals, as well as harming humans.
Additionally, when these algal blooms die, bacteria produced as the algae decompose use up oxygen in the water. This lack of oxygen causes “dead zones” in the water where fish cannot live.
Plastics and garbage
We produce approximately 2.1 billion tons of waste each year. Of this annual waste, 10% comprises plastics. Due to the widespread use of plastics, experts estimate that there is 75 to 199 million tons of waste plastic in the world’s oceans.
Plastic and garbage can enter the water in many ways:
- debris falling off ships
- trash blowing into the ocean from landfills
- garbage swept into the sea via rivers from people discarding used items such as food packages
- people throwing their trash on to the beach
Once in the water, plastic and garbage can harm marine life and human health. Fish may eat trash, mistaking it for food, and end up dying.
As plastic slowly breaks apart, microplastics form. These are small fragments of plastic that are less than 5 millimeters in size. Fish may consume these microplastics, which may then be eaten by humans.
Oil
Oil pollution can occur when oil tankers spill their cargo. However, oil can also enter the sea via factories, farms, and cities, as well as via the shipping industry.
Radioactive waste
Radioactive waste can endure in the environment for thousands of years, making safe disposal difficult. If improperly disposed of, it can enter the water, making it hazardous to humans, marine life, and the environment.
Fracking
Fracking is the process of extracting oil or natural gas from rock. The technique uses large amounts of water and chemicals to crack the rock at high pressure. The fluid created by fracking contains contaminants that can pollute underground water supplies.
Climate change
Emerging studies suggest that rising sea levels due to climate change may negatively affect the quality and safety of drinking water.
The following are some negative ways water pollution can directly affect human health.
Ingesting microplastics
A person may ingest microplastics through drinking water or by eating contaminated seafood. One
Studies show microplastics may cause oxidative stress, inflammatory reactions, and metabolic disorders in humans. However, further research is needed to confirm these effects.
Consuming water contaminated by sewage
The WHO notes that globally, around
According to the WHO, every year, approximately
Drinking water containing chemical waste
Chemical pollutants, such as pesticides, fertilizers, and heavy metals, can cause serious health problems if ingested.
A person who ingests chemical toxins in their water can be at risk of:
- cancer
- hormone disruption
- altered brain function
damage to immune and reproductive systems- cardiovascular and kidney problems
Swimming in contaminated water can also trigger:
- rashes
- pink eye
- respiratory infections
- hepatitis
A person who wishes to reduce water pollution can help by:
- reducing plastic usage and recycling plastics when possible
- disposing of household chemicals properly
- keeping up with the maintenance of their vehicle to ensure it is not leaking harmful substances
- avoiding using pesticides
- making sure to clean up dog waste
- making sustainable choices regarding food and drinks
- considering going vegan or vegetarian
Water pollution is a serious environmental issue caused by many contaminants. Consuming, entering, or washing in polluted water can affect human health.
There are various ways to help to limit water pollution. If a person experiences any effects of water pollution, they should speak to their doctor.