Fluoride In Drinking Water (Ultimate 2023 Guide)

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Fluoride In Drinking Water

Fluoride in drinking water is a highly debated topic. On one hand, fluoride is a mineral that occurs naturally in water and is added to many community water systems to prevent tooth decay. However, ingesting too much fluoride in drinking water can have serious health effects, particularly for pregnant women and children.

In this article, we will discuss what fluoride is, why it’s in drinking water, and if it is safe to consume. Finally, we will share how to test for and remove fluoride from your tap water if you have high levels of it.

What Exactly Is Fluoride

Fluoride is a naturally occurring trace mineral found in many water sources. It is also widely used in dentistry to fortify the enamel and the outer surface of teeth and prevent tooth decay.

Fluoride is added to many community water systems in numerous countries, including the US, as part of a public health program to prevent cavities or tooth decay. This process is known as water fluoridation.

Chemical SymbolF−
EPA LimitMCL: 4.0 mg/L
Side EffectsDental fluorosis, thyroid dysfunction, reduced IQ
Best TreatmentReverse osmosis, water distillation, activated alumina

Why Is Fluoride In Drinking Water?

Fluoride Water Treatment

The presence of fluoride in drinking water can be natural due to the composition of soil and bedrock. In some areas of the country, elevated levels of fluoride may dissolve easily into groundwater as it passes through rocks and gaps.

However, fluoride is primarily added to community water systems because it has been proven to prevent tooth decay. This process is called water fluoridation. This is typically done by adding one of three compounds: sodium fluoride (NaF), fluorosilicic acid (F6H2Si), or sodium fluorosilicate (NaSiF6) to water supplies.

According to the World Health Organization and the Centers for Disease Control, fluoridation promotes the remineralization of teeth, which strengthens their enamel and reduces tooth decay. Community water fluoridation is a public health intervention that can provide benefits regardless of age, income, or education level – but there are aspects to be aware of.

Studies have shown a linear relationship between fluoride exposure during pregnancy and in developing children with a reduced IQ. For example, babies being fed formula using fluoridated tap water can be directly exposed to heightened fluoride levels, putting them at greater risk of adverse neurotoxic effects.

Note: Unlike the fluoride compounds found in toothpaste or supplements, fluoridation chemicals like fluorosilicic acid are not pharmaceutical-grade and have been shown to increase arsenic and lead levels in drinking water.

What Are The Benefits Of Fluoride In Drinking Water?

The benefits of community water fluoridation rest upon the merits of dental health. This is particularly important for children and adults who may not have access to dental care. However, these dental benefits are topical in nature and fluoride is not meant to be ingested.

Proponents claim the following advantages of having fluoridated drinking water in community water systems:

  1. Strengthens tooth enamel. Fluoride helps to harden tooth enamel, making it more resistant to the acid produced by bacteria in the mouth that can cause decay.
  2. Protects against cavities. Fluoride can penetrate the tooth’s surface and protect against the demineralization process that can lead to cavities.
  3. Reduces the incidence of tooth decay. Studies have shown that communities with fluoridated water supplies have a lower incidence of tooth decay, especially in children.
  4. Saves healthcare costs. By reducing the incidence of tooth decay, fluoridation of community water supplies can save individuals and communities significant healthcare costs associated with treating cavities and related oral health procedures.
  5. Easy and affordable. Adding fluoride to drinking water is a simple and cost-effective way to improve dental health, as it requires no individual effort or expense.

What Are The Side Effects Of Fluoride In Water?

While there are topical benefits to fluoride, ingesting it is generally not recommended. Excessive exposure to fluoride and ingesting too much can have adverse health effects. The disadvantages of fluoride in drinking water include:

  1. Cause dental fluorosis. Excessive fluoride exposure during tooth development can lead to dental fluorosis, a condition that affects the appearance of tooth enamel, causing white spots or streaks.
  2. Cause skeletal fluorosis. Long-term exposure to high fluoride levels can cause skeletal fluorosis, a condition that affects the bones and joints, leading to pain and stiffness.
  3. Lead to thyroid dysfunction. Studies have shown fluoride can interfere with thyroid function, particularly in people with iodine deficiency.
  4. Neurological effects. Some studies have demonstrated that excessive fluoride exposure may lead to cognitive impairment, including lower IQ scores.
  5. Results in acute toxicity. In rare cases, acute fluoride toxicity can occur, causing symptoms such as nausea, vomiting, and abdominal pain. This is typically seen with ingesting large amounts of fluoride, such as from accidental swallowing of fluoride-containing products.

How Much Flouride Is Allowed In Drinking Water?

The Environmental Protection Agency’s (EPA) enforceable limit for fluoride in drinking water from public water systems is 4.0 mg/L. This is the safe level set to protect against skeletal fluorosis, which causes joint pain and tenderness.

Additionally, the EPA has a non-mandatory guideline for fluoride in drinking water of 2.0 mg/L, which is suggested to prevent tooth discoloration and pitting in children during the pre-eruption period. While water systems are not obligated to adhere to these secondary standards, the EPA does require them to notify customers if the average levels exceed the guideline.

The current EPA maximum contaminant level goal was set in 1986 and has not been updated to reflect any of the latest health studies related to neurotoxicity.

The World Health Organization (WHO) has separately recommended a limit of fluoride in drinking water of 1.5 mg/L.

Note that the maximum concentration of fluoride in drinking water for children under 8 years should be less than 0.6 mg/L to protect against dental fluorosis.

How To Test For Fluoride In Drinking Water

If you want to detect the exact levels in your tap water, there are a few ways to test for fluoride. Here are the best methods:

Certified Lab Test

Lab tests are the most accurate way to determine the fluoride levels in your drinking water. With a lab water test, you order a testing kit that comes with everything you need to properly collect a water sample to send to the lab.

I recommend the Freshnss Labs water test kit that scans for not only fluoride but also chlorine and other common contaminants. You simply fill the provided sample bottles with your tap water and submit them to the lab. A certified water expert will then analyze your water sample.

When the analysis is complete, you receive a detailed report that will include the exact concentration levels, any health or plumbing risks, and the best treatment methods based on your test data.

Laboratory Water Test Kit

Tests for fluoride, chlorine, and dozens of other contaminants
Analyzed in a certified laboratory
Includes detailed report with EPA benchmarking and safety concerns

DIY Test Strips

Alternatively, you can use DIY fluoride test strips designed to detect the presence and levels of fluoride in water. These test strips can be purchased online or at hardware or home improvement stores.

To use them, you need to dip the test strip into a sample of your drinking water and wait for the results to appear on the strip. Wait 5 minutes for the color to change on the test strip and compare it to the provided color chart to identify the concentration level.

The downside with at-home test strips is they are not very accurate. In some cases, you can get a false positive or it may not show any fluoride is present when there is.

Search EPA Consumer Confidence Reports

Another way to discover the fluoride levels in your drinking water is to search for your local EPA Consumer Confidence Report (CCR) by zip code. The EPA requires these reports, which your water supplier provides annually. They contain information about the source of your drinking water, any contaminants present, and the fluoride levels and other minerals in your water supply.

If you have concerns about the fluoride levels in your zip code’s drinking water, you should contact your local water supplier or public health department for more information. They can provide you with additional resources and guidance on testing your water and addressing any potential issues.

Is There Fluoride In Bottled Water?

Yes, some bottled water contains fluoride if it is sourced from a spring with fluoride exposure or if the bottling company adds it. If fluoride is contained in bottled water, it may be specifically labeled as fluoridated, although it is not required for trace amounts.

Bottled water can be sourced from various places, such as springs, wells, and municipal supplies. While fluoride is naturally present in some bottled water sources, most bottlers remove it to avoid potential legal liability.

In the United States, bottled water is regulated by the Food and Drug Administration (FDA) and must meet a more strict standard than tap water. The FDA requires the total amount of fluoride cannot exceed 0.7 mg/L in bottled water.

Fluoridated bottled water is available in some areas and is labeled as such. If you prefer to drink water without fluoride, consider choosing bottled water treated by reverse osmosis or distillation, as these methods remove most minerals and impurities from the water, including fluoride.

What Other Ways Are People Exposed To Fluoride?

Fluoride Exposure

Aside from fluoride in drinking water, there are other sources of fluoride exposure. These sources include personal care products and some foods. In this section, we will explore the various ways in which people can be exposed to fluoride.


Most toothpaste contains fluoride as it helps prevent tooth decay. When you brush your teeth with fluoridated toothpaste, you can ingest some of it, especially if you don’t rinse your mouth thoroughly after brushing.

Mouth rinses

Many mouth rinses also contain fluoride as an active ingredient, and using these products can expose you to additional amounts of fluoride.

Specific types of foods and beverages

Some foods, particularly seafood, and tea, can contain naturally occurring fluoride. Additionally, processed foods generally have higher levels of fluoride than unprocessed ones due to the use of heavily fluoridated public water during production and modification. This leads to increased fluoride levels in the final products.

Infant formula

Many infant formula brands contain added fluoride, which can contribute to a child’s total fluoride intake. Infants who are exclusively formula-fed may have a higher risk of developing dental fluorosis, a condition characterized by white streaks or spots on the teeth if the formula is mixed with fluoridated water.


Fluoride supplements are sometimes prescribed by dentists or doctors to people at high risk of cavities or who don’t have access to fluoridated water.

Fluoride treatments

In addition to fluoride in toothpaste and mouthwash, dentists may apply fluoride treatments directly to the teeth during dental appointments.

Air pollution

Some industrial processes can release fluoride into the air, which can be inhaled by people living nearby.

Pesticides and fertilizers

Certain pesticides and fertilizers contain fluoride and nitrate which contaminates groundwater and can end up in drinking water.

Industrial sources

Fluoride is also released into the environment from specific industrial processes, such as aluminum smelting and phosphate mining, which can contaminate air and water sources.

It’s worth noting that while exposure to fluoride through these sources is generally considered safe, excessive exposure can lead to health problems. For example, swallowing large amounts of toothpaste or mouth rinse can lead to stomach upset, while consuming too much fluoride over an extended period can lead to dental fluorosis, skeletal fluorosis, or other health issues.

How To Remove Fluoride In Drinking Water

If you are concerned about the level of fluoride in your drinking water, several filtration methods are available to remove it. These treatment options include:

Reverse Osmosis

This is a common and effective method to remove fluoride from drinking water. Reverse osmosis systems use a semi-permeable membrane to filter out impurities, including fluoride. This method can remove up to 99% of fluoride from your water.

The most popular RO system is installed under the kitchen sink as a point-of-use filter. If you cant modify your plumbing, you can also get a countertop RO system.

Water Distillation

Distillation involves boiling water and collecting the steam, which is then condensed into a separate container. This method can remove fluoride from water but also remove minerals and other beneficial substances. Although it’s effective, distillation is less efficient than reverse osmosis or activated alumina de-fluoridation and can be more expensive.

Activated Alumina Defluoridation

This method involves using activated alumina to remove fluoride from water. Activated alumina is a highly porous material that can absorb fluoride ions. This method effectively removes fluoride from water but may require frequent replacement of the activated alumina.

It is essential to note that while these methods can remove fluoride from drinking water, they may also remove beneficial minerals. Therefore, it is crucial to ensure that you get enough minerals in your diet or consider using a mineral supplement.

If you have questions on how to determine the best method for removing fluoride from your drinking water, such as water quality, flow rate, and sizing – feel free to contact us for help!

Frequently Asked Questions

What is fluoridation in drinking water?

Fluoridation is adding fluoride to community water systems to improve dental health. The US Public Health Service recommends an optimal level of 0.7 milligrams of fluoride per liter for community water systems.

Is fluoride in drinking water toxic?

Fluoride is not toxic in low levels and can help prevent tooth decay. However, if your fluoridated drinking water contains high levels of fluoride, it can result in dental fluorosis, a condition that affects the appearance of tooth enamel. In very high levels, fluoride can cause skeletal fluorosis, which affects the bones.

Where does the fluoride in water come from?

Fluoride in water can come from natural sources such as rocks, soil, and minerals. Water naturally absorbs fluoride from these sources as it travels through the ground. Additionally, some areas may have higher fluoride levels due to geological factors. Water fluoridation is the process of adjusting the level of fluoride in drinking water to an optimal level that can help prevent tooth decay. 

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