What are the Most Common Drinking Water Contaminants?

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Water is essential to our survival. It’s also very important to our health. Unfortunately, we often drink contaminated water. There are many contaminants in our drinking water supply that can cause health problems. In fact, according to the EPA, over half of Americans get sick from drinking unsafe water.

Most of us drink water every day without even thinking about it. But how safe is our drinking water really? In this article, I’ll go over the top 5 most common contaminants found in drinking water and explain why they’re dangerous. I’ll also explain how to remove water contaminants in your water.

most common drinking water contaminants

Contamination of Drinking Water

The contamination of drinking water occurs when harmful substances enter our bodies via the water we drink. These contaminants may include bacteria, viruses, heavy metals, pesticides, herbicides, pharmaceuticals, industrial chemicals, and many others.

Some of these contaminants can cause serious health problems, such as cancer, birth defects, and neurological disorders. Other contaminants can lead to minor illnesses like diarrhea, skin rashes, and headaches.

There are many different ways that contaminants can enter our bodies, including by eating contaminated food, breathing polluted air, or coming into contact with contaminated surfaces.

The best way to prevent the contamination of drinking water, however, is to filter it properly.

Types of Drinking Water Contaminants

There are several types of drinking water contamination. Physical contaminants are those that affect the physical properties of water. Some examples of physical contaminants include sediment or organic matter suspended in the water of bodies of water from soil erosion.

Chemical contaminants are elements or compounds that are added to water. These chemicals may be naturally occurring or manufactured. Some examples of chemical contaminants include chlorine, ammonia, nitrates, phosphates, heavy metals, and pesticides.

Biological contaminants are living organisms found in water. They are sometimes called microorganisms or microbiological contaminants. Some examples of biological contaminants include bacteria, viruses, and parasites.

Radiological contaminants are radioactive isotopes that are emitted by natural sources or man-made activities. Some examples of radiological contaminants include iodine-131, strontium-90, cesium-137, and plutonium-239.

Most Common Drinking Water Contaminants

1. Lead

Lead is one of the most dangerous contaminants found in drinking water. Lead poisoning can cause serious health issues including brain damage, learning disabilities, behavioral disorders, and even death.

According to the CDC, there are approximately 5 million children under the age of 6 who have elevated blood levels of this heavy metal.

2. Chlorine

Chlorine is used to treat our drinking water to prevent illness and disease. Unfortunately, it also reacts with organic compounds in wastewater, turning them into carcinogens.

These chemicals include chloroform, bromodichloromethane, trichloroethylene, and dichloroacetic acid. Chlorination is not only dangerous to humans, but it also harms aquatic life.

3. Arsenic

Arsenic is a naturally occurring element that is commonly found in rocks, soil, and groundwater. Arsenic is not considered toxic at low levels, but high doses can cause cancer and birth defects.

High doses of arsenic can lead to skin lesions, hair loss, nausea, vomiting, diarrhea, abdominal pain, headaches, fatigue, weakness, numbness, tingling, joint pain, muscle cramps, difficulty breathing, confusion, memory problems, seizures, coma, and death.

4. Radon

Radon is a naturally occurring radioactive gas that occurs deep underground. It seeps into groundwater and accumulates in buildings. Radon is colorless, odorless, tasteless, and non-toxic. However, it does cause lung cancer in about 21 thousand people each year.

According to the Centers for Disease Control and Prevention, radon is the second leading cause of lung cancer after cigarette smoking. People exposed to high levels of radon may develop lung cancer at younger ages than smokers.

5. Nitrate

Nitrate contamination is one of the most common contaminants found in drinking water. Nitrates come from fertilizer runoff and sewage treatment plants. These compounds are naturally occurring, but high levels can cause health problems.

High levels of nitrates have been linked to increased rates of childhood asthma and lower respiratory infections. Children are particularly vulnerable to these effects because their lungs are still developing.

To reduce the risk of nitrate exposure, try to limit your consumption of processed meats and dairy products. You should also avoid eating foods grown near polluted waterways.

How Drinking Water Can Be Contaminated

Drinking water can become contaminated through several different means. One of the most common sources of contamination is storage tanks. These tanks hold the water until it is needed at homes and businesses. However, if the tank isn’t properly maintained, it can leak chemicals and road salts into the water supply.

Another source of contamination comes from septic systems. These systems are used to treat wastewater and dispose of household waste. Unfortunately, they can contaminate groundwater if not properly maintained.

Another major source of contamination comes from uncontrolled hazardous waste. Many industries produce toxic substances that end up being dumped into landfills. As these landfills break down, they release harmful gases into the air.

Finally, atmospheric pollutants can enter our drinking water supplies through rainwater runoff. Rainwater picks up toxins from the ground and carries them into lakes, rivers, and streams.

How Dangerous are the Contaminants of Water for People’s Health?

Contaminants of water vary in danger from no noticeable effects at lower concentrations to extreme danger including death. Heavy metals and chemicals such as Arsenic, Mercury, Chromium, and Lead cause chronic damage to organs such as the Liver, Kidney, Brain, Endocrine, and Reproductive Organs.

Biological contaminants cause a variety of “water-related diseases” according to the World Health Organization. These most commonly include Diarrhea, Typhoid, Amoebic, and Bacterial Dysentery which affect over one billion people and cause two million deaths annually.

The high level of danger from biological contaminants and their associated conditions is clear when we look at Morbidity and Mortality Associated with Water Pollution.

According to the World Health Organization, approximately 2 billion people lack safe drinking water, and approximately 829 thousand people died each year from water pollution-related diseases, chiefly Infectious Diarrhea. This map shows the number of people without safe drinking water by country.

How to Remove Water Contaminants in Your Water

There are several methods available to remove water contaminants from your water. You can install a filtration system, which removes contaminants using physical, chemical, or microbiological processes. A distillation system boils the water and collects the steam in a separate container while leaving behind many solids and dissolved contaminants. A disinfection system uses chemicals (chlorine, ozone), UV light, electronic radiation, or heat to kill and/or destroy pathogens.

Filtration systems are typically installed after the water meter, and they treat all the water entering a building. These systems are effective at removing particulate matter, bacteria, viruses, and organic compounds. However, they do not remove heavy metals, radium, arsenic, lead, mercury, nitrates, pesticides, herbicides, pharmaceuticals, hormones, industrial chemicals, and other toxic substances.

Distillation systems effectively boil the water and collect its vapor in a separate container, thus concentrating the contaminants. While distillation systems are effective at reducing the concentration of certain contaminants, they cannot eliminate them entirely.

Disinfection systems use chemicals (chlorine, ozonide, hydrogen peroxide, chlorine dioxide, etc.) to kill and/or inhibit microbial growth. Chlorine is the most commonly used disinfectant because it is inexpensive, readily available, and highly effective against most microbes.

Benefiting from Removing Contaminants in Your Drinking Water

There are many benefits to removing contaminants in your drinking water. First, it ensures that you always have clean, fresh water available.

Second, it protects your family from diseases caused by contaminated water. Third, it prevents damage to your plumbing system.

Fourth, it reduces the amount of money you spend on bottled water. Fifth, it improves the taste of your water. Finally, it keeps your house free of germs and bacteria.


How Do I Know If My Water is Safe?

The best way to ensure that your drinking water is safe is to test it yourself. There are many different ways to test your water, but the easiest method is to boil it for two minutes.

Is It Safe to Drink City Tap Water?

City tap water is generally safe to drink. However, there are certain precautions you should take to ensure that you’re getting the best possible water.

How to Make Water Taste Better?

The best way to improve the flavor of water is to filter it yourself. There are many different ways to go about filtering water, but the easiest method is to install a whole-house filtration system.


In conclusion, tap water is generally safe to drink, but it’s never 100% guaranteed. That said, there are several things you can do to keep your water clean and free from harmful bacteria.

First, make sure that you boil your water for at least five minutes before using it. This kills almost all of the germs that cause illness. Second, use bottled water whenever possible.

Bottled water is usually safer than tap water because it has been filtered through a process called reverse osmosis. Finally, avoid buying water from places like gas stations and convenience stores.

These places often sell their water directly from the source, which means that it hasn’t had time to sit around and collect germs. Instead, buy your water from a store where it’s been sitting in a cooler for hours or days.

Joanna G. Lackey

Hi, I'm Joanna, a writer freelance writer who specializes in topics about health and nutrition. I live in the Pacific Northwest with my husband and three children. I'm a mom to two dogs and a cat. I love reading, writing, and taking photos.