Do you know what impurities are in your drinking water?
Clean drinking water is a necessity for good health, but not all of it is safe. There are many contaminants that can cause serious health problems if consumed over long periods of time. If you want to make sure the water you drink every day is clean and pure, read on!
In this article, you’ll learn about the different types of treatment methods, common contaminants found in drinking water, and how they can be removed. We also answer frequently asked questions about standards for safety and regulations for drinking water quality. Finally, we provide tips on how to choose a reliable source for your purified drinking water needs.
Let’s get started!
Table of Contents
What Impurities Are in Drinking Water
The United States has the safest and purest drinking water in the world. However, there are still impurities that can be found in water supplies, depending on the location. Impurities can come from natural and man-made sources.
Some common impurities that may be present in drinking water include:
- Microorganisms such as bacteria, viruses, and parasites
- Disinfectants such as chlorine and chloramines
- Pesticides and herbicides
- Fuels and solvents
- Metals such as arsenic and lead
- Radionuclides such as uranium and radium
- Taste and odor
Each of these impurities poses a different level of health risk. For example, while bacteria and viruses may cause short-term gastrointestinal problems, chemicals like chlorine can lead to long-term health issues such as cancer. It’s important to know what impurities are in your drinking water so you know what take steps to remove them.
How do contaminants get into our water?
There are many ways that contaminants can get into our drinking water. Some common sources include:
- Pollution from agricultural and industrial activities
- Leaking septic tanks, landfills, and storage tanks
- Runoff from roads and parking lots
- Municipal wastewater treatment plants
- Improperly installed or maintained home plumbing systems
- Incorrect use of fertilizers and pesticides
- Storm water runoff
Drinking water can also become contaminated during the distribution process, such as when it travels through old or corroded pipes.
It’s important to be aware of the many ways that contaminants can enter our drinking water so we can take steps to reduce their impact.
How many chemical contaminants are there to worry about?
In the United States, there are more than 80,000 industrial chemicals registered with the National Toxicology Program. This is the government program is responsible for identifying potentially hazardous substances and evaluating their effects on our health. Unfortunately, most of these chemicals haven’t been tested or studied to determine how dangerous they are.
The federal legislation that protects our drinking water is the Clean Water Act (CWA) and the Safe Drinking Water Act (SDWA). These laws require the US Environmental Protection Agency to set limits for contaminants in our water.
Under the CWA, the EPA regulates just over 100 chemicals. The SDWA sets limits for 90 chemical in our drinking water. This is just a tiny fraction of the chemicals that are registered with the National Toxicology Program.
So, while we know about some of the contaminants that can be found in our drinking water, there are many more that haven’t been studied or regulated. It’s important to be aware of these and take steps to reduce their impact on our health.
How bad is the problem?
In 2015, nearly 77 million Americans were drinking water from systems that violated federal protections. More than a third of this number relied on sources which did not comply with standards put in place to protect health; millions more had no idea if their supplier was doing everything they could possibly be required by law too—or worse yet: many times these providers failed outright when it came down test results
In addition, many people get their drinking water from a private well. These water supplies are not regulated and do not require testing. So, it’s impossible to know what contaminants may be present in them.
The bottom line is that there are many ways that impurities can find their way into our drinking water, and we don’t always know what they are. It’s important to take steps to reduce their impact on our health.
Treatment Methods to Purify Drinking Water
Clean drinking water is an essential element of our health. Yet, many of us take it for granted. We turn on the tap and expect water to come out clean and safe to drink. Sadly, this is not always the case.
Fortunately, there are many ways to treat and purify drinking water. Let’s take a look at some of the most common methods:
- Activated carbon filtration
- Advanced oxidation process
- Disinfection with chlorine, iodine
- Ion exchange resins
- Reverse osmosis
- Specialty adsorbants and resins
- Ultraviolet light disinfection
- Water softener
1. Activated carbon filtration
Activated carbon is one of the oldest and best understood treatment methods used. Carbon is made from charcoal that has been treated with high-temperature steam to create lots of tiny pores. These pores adsorb (or grab on to) contaminants in the water.
Activated carbon filters are usually used in conjunction with other treatment methods, such as sediment filtration and disinfection. They can be effective at removing many common chemicals, including chlorine, pesticides, and solvents.
However, they are not effective at removing heavy metals or bacteria. And, they can only be used to treat water that is relatively clean to start with. They are not effective at treating water that is heavily contaminated.
Activated carbon filters should be replaced every few months, depending on the amount of water they treat and the type of contaminants they remove.
Read my comprehensive article on how to design an activated carbon system.
2. Advanced oxidation process
The advanced oxidation process (AOP) is a relatively new treatment method. It uses ultraviolet light combined with a power oxidizer like ozone or hydrogen peroxide to break down chemicals in the water. The contaminants are destroyed and converted into harmless byproducts – usually carbon dioxide and water.
Ozone is created by passing oxygen gas through an electric current. Ultraviolet light is a type of electromagnetic radiation. It is used to kill bacteria and viruses.
AOP systems can be effective at removing many common contaminants, including pesticides, solvents, and heavy metals. They are also effective at killing bacteria and viruses.
However, they are not effective at removing inorganic compounds like heavy metals or arsenic. And, they can be expensive to install and operate.
AOP systems should be regularly serviced and monitored to ensure that they are working properly.
Boiling water is a simple, effective way to kill most bacteria and viruses. It also removes many other contaminants, including volatile organic compounds and many pesticides.
However, boiling does not remove dissolved solids or heavy metals. It is not effective at treating PFAS, an emerging contaminant. What’s worse, the evaporation of water actually concentrates the impurities which makes the water more toxic.
Boiling is a good emergency treatment method, but it is not a good everyday process to rely upon.
4. Disinfection with chlorine, iodine
Disinfection is the process of killing or disabling bacteria and viruses. There are several methods that can be used, but each involves using a disinfecting agent such as chlorine, iodine, and ultraviolet light.
Chlorine is a common disinfectant that is widely used in water treatment plants. It is also found in many household products, such as bleach. Chlorine is effective at killing most bacteria and viruses. However, it can also react with organic compounds to form harmful byproducts.
Iodine is a common disinfectant that is used in portable water treatment systems. It is effective at killing bacteria and viruses, but it can also be corrosive to metals. Drinking water treated with iodine can upset your stomach and isn’t really suitable as a permanent treatment method.
Ultraviolet light is a type of electromagnetic radiation. It is used to kill bacteria and viruses. Ultraviolet disinfection is a common treatment method in water treatment plants. It is effective at killing most bacteria and viruses, and it does not produce any harmful byproducts.
Each of these methods have their own advantages and disadvantages. It is important to choose the right one for your needs.
Distillation is one of the oldest and most reliable ways to purify water. It involves boiling water and then collecting the steam and condensing it. The condensed liquid is free of the impurities and safe to drink. The impurities are either evaporated as a gas or remain behind as a solid.
You can use a countertop distillation unit or a whole-house system, depending on your needs.
Distillation is effective at removing most impurities, including bacteria, viruses, heavy metals, and dissolved solids. It also removes volatile organic compounds and many pesticides.
However, it is not effective at treating substances that have lower boiling points than water such as oils, petroleum and alcohol. It is also expensive to install and operate.
Distillation should be regularly checked for sediment and other impurities that can build up over time.
There are a wide variety of particle filters available for drinking water. They range from simple pitcher filters to complex whole-house systems.
The most common type is the sediment filter, which removes sediment and other solid particles from the water. They also remove rust, turbidity, and other impurities. Many other treatment processes use particle filters as a form of pre-treatment to prevent fouling and plugging.
Sediment filters should be replaced every few months, depending on the amount of water they treat and the amount of suspended particles in the water. Filter cartridges should be replaced when they become clogged or saturated with impurities.
You need to pay attention to the filter size to ensure it is fine enough to remove small diameter particles. You can specify a filter to remove small impurities like bacteria and viruses or larger particles like rust and sand.
7. Ion exchange resins
Ion exchange resins are small, porous beads that attract and hold certain ions. They are used in water treatment to remove dissolved solids, including heavy metals like arsenic and lead.
Ion exchange resins can be used in a variety of systems, including pitcher filters, countertop units, and whole-house filters.
They work by exchanging the unwanted ions for ions of a different kind. The unwanted ions are then either removed from the resin through a process known as regeneration, or the spent media is replaced with fresh material.
Ion exchange resins should be regularly replaced, depending on the amount of water they treat and the type of resin used.
They can also become clogged over time and need to be cleaned or replaced.
Arsenic is a common contaminant in water and can be difficult to remove. Ion exchange resins are one of the most effective ways to reduce arsenic levels.
Lead is another common contaminant in water and ion exchange resins are an effective way to remove it.
Precipitation is a treatment process that uses a chemical to cause impurities to form solid particles that can be removed from the water. The most common precipitating agent is alum, but other chemicals are also used.
The process works by adding the chemical to the water. This causes the impurities to form insoluble particles that can be easily separated from the water through settling or filtration. Sometimes a coagulant is used to help the particles form.
The precipitated solids are either removed from the water or allowed to settle out over time. The treated water is then filtered to remove any remaining particles.
Precipitation is a simple and effective treatment process, but it can take some time for the solids to settle out. It also requires careful monitoring to ensure the correct chemical is used and the water is properly filtered.
This treatment process is not typically used in a residential setting because of the skill required to implement it properly.
9. Reverse osmosis
Reverse osmosis is a water treatment process that uses pressure to force water through a semipermeable membrane. This membrane allows water molecules to pass through while rejecting other particles, including dissolved minerals and bacteria.
Reverse osmosis is used in a variety of settings, including residential drinking water systems and industrial wastewater treatment plants.
It is one of the most effective ways to remove dissolved minerals and other impurities from water.
Reverse osmosis systems can be expensive to install, but they are often the best option for removing specific impurities.
They require regular maintenance and replacement of filter cartridges.
RO systems can be installed under your sink to treat the water your drink and cook with, or they can be installed at the point-of-entry to treat all of the water in your house.
Reverse osmosis is an effective way to remove impurities from water, but it can be expensive and requires regular maintenance.
10. Specialty adsorbants and resins
Many contaminants require special adsorption media or resins to remove them from water. These materials are selected because their pore size is ideal for the particular contaminant or it has a high affinity for removing it.
For example, the emerging contaminant 1,4-dioxane is removed using a specially created adsorbent material that can filter it from the water. Read my article on how to remove 1,4-dioxane with specialty media.
11. Ultraviolet light disinfection
Ultraviolet (UV) light is a very powerful disinfectant. It is used to kill bacteria, viruses and other microorganisms in water.
UV light is sometimes used as a primary disinfectant or as an additional step after chlorination.
It is a very effective way to reduce the number of microorganisms in water and does not create any harmful by-products.
UV light systems are relatively inexpensive and easy to operate.
They require periodic maintenance to replace the UV light bulbs.
UV light is a powerful disinfectant that can be used as a primary or secondary step in water treatment.
12. Water softener
Water softener systems are another popular option for removing impurities from drinking water. They work by exchanging hardness minerals, like calcium and magnesium, for sodium. This process makes the water less likely to form scale or lime deposits on fixtures and appliances. It also reduces soap scum and makes clothes and dishes cleaner.
Water softeners are often the best option for treating water that contains high levels of hardness – dissolved calcium and magnesium that creates scale and mineral coatings on your pipes, plumbing fixtures, and other surfaces.
They require regular maintenance to regenerate the resin beads and keep them operating within design limits. Salt pellets are typically used to regenerate the resin. Proper sizing is also important to ensure optimum performance.
Water softener systems are a popular way to remove impurities from drinking water. They work by exchanging hardness minerals for sodium, making the water less likely to form scale or lime deposits.
These are some of the most popular methods for removing impurities from drinking water. Each has its own set of pros and cons, so it’s important to select the right option for your needs.
Read my complete guide to water softeners to learn a lot more about this treatment process.
Whole House versus Point-of-Use Treatment Approach
Once you determine which treatment technology is appropriate for your particular situation, you also need to determine how you will implement it.
You can treat every gallon of water that comes into your house with a point-of-entry (POE) treatment system. Another approach is to just treat the water you drink with a point-of-use (POU) treatment system.
Here are the most common modes of using water treatment technologies:
- POE or whole-house treatment
- POU or under-sink treatment
- Pitcher filters
- Faucet filters
- Refrigerator filters
- Countertop filters
Each of these approaches has advantages and disadvantages.
POE or whole-house treatment systems
A POE system is the most comprehensive way to treat your water. It treats all of the water that comes into your house – from the tap, shower, dishwasher, and washing machine.
This approach is usually more expensive than other methods, but it has several advantages:
- It provides a consistent level of treatment for all of your water needs
- It is usually easier to maintain than a POU system
- You don’t have to remember to change the filters on all of your individual appliances
- They are more rugged and built of higher quality components
- They remove more of the contaminants than other approaches
POE systems are the most comprehensive way to treat your water and provide a consistent level of treatment for all of your needs.
POU or under-sink treatment systems
If you don’t want or need to treat all of your water, a point-of-use system is a good option. This type of system installs under the sink and treats only the water that comes out of the tap.
POU systems are less expensive than POE systems, they are easier to install, and they take up less space.
However, they have several disadvantages:
- They may not be as effective at removing contaminants as a whole-house system
- You have to remember to change the filters on a regular basis
- They may not be as rugged or built of high quality components as a POE system
POU systems are a good option if you don’t want or need to treat all of your water. They are less expensive, easier to install, and take up less space.
Pitcher filters are a type of POU system. They sit on the counter and filter water as you pour it into a glass or pitcher.
They are inexpensive, easy to use, and don’t require any installation.
However, they have several disadvantages:
- They may not be effective at removing all of the contaminants in your water
- They have lower treatment capacity and efficiency
- They need to be cleaned and sanitized on a regular basis
- The filters need to be replaced often and are relatively expensive
I have a whole-house water treatment system to remove contaminants from my drinking water. I also use a pitcher filter as a secondary level of treatment – just another layer of protection to give me peace of mind for my family’s health.
Faucet filters are a very simple and low-cost way to treat your drinking water. They attach to the faucet and filter the water as you drink it.
They are easy to use and don’t require complicated installation. Most just screw onto the faucet threads where the aerator is located.
However, they have several disadvantages:
- They may not be effective at removing all of the contaminants in your water
- The filters need to be replaced often which adds up quickly
- They don’t perform as well as under-sink or whole-house filters
Most new refrigerators come with a water filter installed in the door or on the supply line. This is a convenient way to treat your drinking water and it’s always cold!
These filters are designed to remove taste and odor compounds – chlorine and some disinfectant byproducts. They also remove trace amounts of some contaminants like PFAS and VOCs.
However, these filters have several disadvantages:
- They are not effective at removing all of the contaminants in your water
- The filters need to be replaced often which can get expensive
- They have limited treatment capacity which requires frequent replacement
- On a gallon treated basis, they are very expensive
Many treatment technologies are available in countertop units. These filters sit on the counter and filter water as you use it.
They are easy to install, don’t require any plumbing or electrical skills, and come in a variety of sizes to fit your needs. They are ideal for renters who aren’t allowed to make permanent modifications to plumbing systems.
However, this mode of treatment can be expensive on a per gallon basis. Countertop units take up valuable space in your kitchen. Sometimes, countertop systems perform less effectively than large, whole-house units.
Common Contaminants and How to Remove Them
We are fortunate that the US has some of the safest and purest drinking water in the world. However, even in the US, water can contain harmful contaminants that can make you sick.
The most common and dangerous contaminants are:
Many of these contaminants are regulated, but not all of them are. In addition, water treatment technologies vary in their ability to remove these contaminants.
The best way to ensure that your drinking water is safe is to have it tested. You can then use the results of the test to determine which type of water treatment system is right for you.
Drinking Water Standards and Safety
Drinking water standards are the safe limits for contaminants in drinking water. These standards are set by the EPA and various state and local agencies.
The Safe Drinking Water Act is a federal law that protects public drinking water supplies from harmful contaminants. The SDWA was passed in 1974 and has been amended several times, most recently in 1996.
The SDWA requires the EPA to set standards for drinking water quality and requires public water systems to comply with these standards.
The EPA develops drinking water regulations based on the best available science. The agency also updates its regulations as new information becomes available.
Public water systems must test their water for compliance with regulatory limits. If a system fails to meet a standard, it must take steps to correct the problem.
The EPA also oversees state and local agencies that set drinking water standards.
The Safe Drinking Water Act is a cornerstone of our nation’s public health protection system. It ensures that all Americans have access to safe, clean drinking water.
Doesn’t the EPA test every chemical to make certain my water is safe to drink?
Unfortunately, the EPA does not have the resources to test every chemical. The agency relies on data from manufacturers and other scientific sources to set safe limits for contaminants in drinking water.
My local water department says my water is safe to drink. Why should I be concerned?
Your local water department may only test for a few regulated contaminants. There may be other harmful contaminants in your
How can I know what contaminants are in my drinking water?
If you get your water from a public supply, they are required to sample it for all of the regulated contaminants. These reports are available on the EPA’s website. However, they only test for the 100 or so chemicals the EPA requires – not the 80,000 chemicals currently in use.
What is a safe level of impurities in my drinking water?
That depends on the contaminant. The EPA sets safe levels for contaminants based on the best available science. However, these standards are always being updated as new information becomes available.
I use a water filter. Does that make my water safe to drink?
It depends on the type of filter you’re using and the contaminant you’re trying to remove. Some filters are effective at removing certain contaminants, while others are not.
How can I be sure that my water filter is working?
You can’t really know for sure unless you have the filter tested by a lab. However, most water filters should be replaced every six months to a year to ensure optimal performance. Check the manufacturer’s recommendations – they designed the filter for a specific service life.
Final Word on Removing Impurities in Drinking Water
There are many different modes of treatment that can be used to purify drinking water. The most common contaminants found in the average household’s tap water include arsenic, nitrates, and lead. Other chemicals such as pesticides or pharmaceutical drugs may also be present depending on where you live.
It is important to remove these impurities from your water before consuming it for health reasons – some have been linked with certain cancers and other serious illnesses! We want everyone to enjoy healthy lives free of disease. This was part of our motivation to put together this list of 12 ways you can use to remove contamination from your drinking water.