Water Quality InformationWritten By Actual Experts


Science-Backed Facts About Fluoride In Drinking Water

Analies Dyjak @ Saturday, April 1, 2017 at 9:06 pm -0400

People regularly come to our water nerds with questions about fluoride in drinking water because they "heard something" or "read something." Unfortunately, most of what's on the internet on this topic is not based on credible science, with a good chunk of it being a flat out lie. To make matters worse, some of the people peddling conspiracy theories used to have legitimate medical practices, but have decided to cash in on their titles and peddle "health products." Instead of cashing in on this hysteria (like a lot of other water filtration companies), we have made the decision to be a credible source of information.

Why Do Cities Add Fluoride To Drinking Water?

Cities add fluoride to drinking water to prevent tooth decay. When fluoride comes in contact with your tooth's enamel, it hardens the surface and makes it resistant to decay. Fluoridated tap water is often the only source of fluoride for lower income populations that do not have access to proper dental care or products. We wrote a more comprehensive article on this topic a little over a year ago.

Is Fluoride Bad For You?

Not in the way that inflammatory/conspiracy theory websites claim.

Most of the well-known side effects of excessive fluoride exposure are cosmetic, for example spots or discoloration of teeth. This typically happens when people expose their teeth to multiple fluoride sources (e.g. tap water, toothpaste, mouth wash). If a dentist notices early symptoms of this, they will often recommend that the patient switch to a fluoride-free toothpaste.

In areas with naturally excessive fluoride concentrations (several times more than what municipalities add to tap water), they can be at higher risk of bone fracture. This is extremely rare in the US.

One recent study that has received a lot of attention recently is looked at an apparent association between tap water fluoridation and hypothyroidism, but the work admittedly did not demonstrate cause & effect. Moreover, since the article was published, other public health scientists have been extremely critical of the work because of the way that groups of people were categorized (suggesting that the original study's researchers manipulated the data to get a desired result).

Is Fluoride Added To Tap Water Because The Government Needed To Find A Way To Dispose Nuclear Waste and Chemical Weapons?

Obviously not. Nuclear waste is stored, and chemical weapons are decomposed.

How Do I Filter Fluoride From Drinking Water?

If you decide that you want to filter fluoride from your water for the right reasons (not out of hysteria), there are a couple of credible options available.


A quality water distiller can remove fluoride from water. The units that we have tested reduced fluoride concentrations between 40-70% of fluoride from the water.

Reverse Osmosis

For people who are willing to accept the downsides, many systems that use reverse osmosis can effectively reduce fluoride levels in drinking water.

Do Hydroviv's Scientists Filter Fluoride In Their Homes?

No. To build a filter that removes fluoride, we'd have to compromise the cartridge's performance against things like lead, arsenic, VOCs, Chromium 6, PFAS and other contaminants where there is conclusive evidence of negative health effects, and as scientists, we're just not comfortable doing this... even upon request. So no, our systems don't remove fluoride.

As always, we encourage people to take advantage of our "Help No Matter What" approach to technical support. Our water quality experts will help you solve your problem, even if you have no intention of buying a Hydroviv Water Filter for your home.

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Analies Dyjak @ Thursday, June 8, 2017 at 6:42 pm -0400

Rebecca Labranche | Laboratory Director, A&L Laboratory

How Is Drinking Water Regulated?

The Environmental Protection Agency (EPA) sets regulatory limits for over 90 contaminants in water provided by public water systems. The EPA sets these limits in accordance with the Safe Drinking Water Act to protect public health in the communities that are using this water. The EPA limits are divided into two main categories. National Primary Drinking Water Regulations are legally enforceable standards that apply to public water systems. Primary standards protect public health by limiting the levels of contaminants in drinking water that negatively affect human health. National Secondary Drinking Water Regulations are non-enforceable guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water. EPA recommends secondary standards to water systems but does not require systems to comply. In addition to the federal EPA standards, The Safe Drinking Water Act (SDWA) gives individual states the opportunity to establish their own drinking water standards if they are not more lenient than those set by the EPA's national standards.

So how do these federal and state regulations effect private well-owners? These same limits and guidelines used for public water are also adopted by most institutions and lenders for home water testing as a way to determine if the property provides potable, safe water. When a home goes up for sale, if the buyer is financing, they will likely be required to test the water. While lenders may be concerned about a potable water source in order to protect their investment, there are no official rules or regulations for determining potability of private wells. Many states and towns do not even require sampling of private wells after installation. It is the responsibility of the homeowner to maintain their well and water supply. 

How Often Should Home Water Testing Be Conducted?

Private well water should be tested a minimum of once per year. Drinking water supplies obtained from shallow dug wells and surface water sources should be tested more frequently as they are more susceptible to contamination. Annual testing of both dug and drilled wells should check for the most common contaminants which are bacteria, nitrates and nitrites. Even if your water has consistently been safe to drink in the past these parameters could change without you knowing and affect the safety of your water. New drilled wells should be tested with a more comprehensive water test which includes bacteria, nitrates, nitrites, metals, minerals and radon. This test identifies many common primary and secondary contaminants typically found in the bedrock surrounding the well. This comprehensive test should be repeated every 3 – 5 years to ensure the well is still providing safe water.

What Are The Most Common Types Of Drinking Water Contaminants?

Drinking water contaminants can be divided into several categories: Inorganic Chemicals, Organic Chemicals, Radionuclides and Microorganisms. Testing for every possible analyte would be prohibitively expensive but we have put together a comprehensive test package which covers common problems found in our area.

Total Coliform





















Laboratories throughout the United States will offer similar packages based on the geology in their area.

What Is The Process For Analyzing Drinking Water?

The process of analyzing drinking water varies by laboratory and their methods used. However, the basic premise is the same for all of them. The first step is to obtain a water test kit from the certified drinking water laboratory that you intend to use for the analysis. Home water testing kits are specific to each laboratory and their methods so it is important not to use another laboratory’s bottles. These test kits come with all the information that is needed to collect the sample and get it back to the laboratory in the required time frame. The sampling instructions are usually step by step and easy to follow. Once the water is received by the laboratory it will be analyzed for the requested parameters and report will be generated and sent back to the client. The typical turn-a-round time for a comprehensive water test is 2-3 business days.

Using a certified laboratory is very important. They are monitored by their state and undergo periodic inspections to ensure that they are producing the highest quality data. During these inspections their instruments, standard operating procedures, lab technicians, quality control documentation and reporting procedures are reviewed and evaluated. If anything is found to be out of compliance certification for the laboratory can be revoked. In addition to inspections, they also have to complete proficiency tests for each method they conduct to prove that they can perform the method properly and obtain results within the specified limits.

What Are The Risks Associated With Consuming And/Or Using Contaminated Water?

The risks vary greatly depending which contaminants you have in your water. Common health effects include gastrointestinal illness, reproductive problems, neurological disorders and cancer. These health problems pose a greater threat to young children, pregnant women, the elderly, and people with compromised immune systems. The health effects of drinking contaminated water can range from no physical impact to severe illness or even death.

Some of the effects of drinking contaminated water are known almost immediately. Immediate health related issues generally stem from contamination by pathogens such as total coliform and E.coli. Symptoms include gastrointestinal and stomach illnesses such as nausea, vomiting, cramps, and diarrhea.

Other contaminants pose health effects that may not be observed for many years. Some of the most common ones are:

Arsenic in water occurs naturally as well as from industrial activities. Studies have shown that chronic or repeated ingestion of water with arsenic over a person’s lifetime is associated with increased risk of cancer (of the skin, bladder, lung, kidney, nasal passages, liver or prostate) and non-cancerous effects (diabetes, cardiovascular, immunological and neurological disorders).

Lead can occur due to corrosion of lead containing household plumbing and by industrial pollution. Major toxic effects include anemia, neurological dysfunction/damage and renal impairment.

Uranium is a tasteless, colorless, odorless contaminant. Drinking water with uranium amounts exceeding 30ug/L can lead to increased cancer risk, liver damage, or both.

Copper has both long term and short term effects. Some people with short term exposure, experience gastrointestinal distress, and with long-term exposure may experience liver or kidney damage. It is typically introduced into the water from household plumbing systems.

Fluoride has been shown to reduce tooth decay in children's teeth if they receive an adequate level. The optimal concentration, as recommended by CDC is approximately 1.1 mg/L. In the range of 2.0-4.0 mg/L of fluoride, staining of tooth enamel is possible. Above 4.0 mg/L, studies have shown the possibility of skeletal fluorosis, as well as the staining of teeth.

Radon is the second leading cause of lung cancer. High levels of radon gas occur naturally in Maine soil and water, and can move up into a house from the ground. The house then traps the radon in the air inside. Radon gas can also dissolve into well water, which is then released into the air when you use the water.

What Should I Do If The Laboratory Finds Something In My Water?

If tests on your water indicate problems, the next step is to determine what type of system you need to treat the water. This can be a difficult decision because there is a wide variety of water treatment devices on the market today. Water purifiers range from relatively low-cost, simple filter devices for a kitchen faucet to more expensive, sophisticated systems that treat water from its point of entry into a home. Keep in mind, no one water treatment device can solve every problem.

Rebecca Labranche, the Laboratory Director for A & L Laboratory. A & L Laboratory which specializes in drinking water analysis for both public systems and private wells, throughout the State of Maine.

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Fluoride and Tap Water: Brief History, Summary of Science, and Takeaways

Analies Dyjak @ Monday, July 25, 2016 at 1:14 pm -0400

Eric Roy, Ph.D.  |  Scientific Founder

Since starting Hydroviv, the most heated questions that our support team receive often deal with the issue of fluoride in tap water, mostly due to the conflicting "information" found on the web. There are a lot of different factors that contribute to the “Fluoride Controversy” and the goal of this article is to lay out some historical context and give a non-exhaustive summary of the credible science.

Fluoride and Dental History:

The origin of fluoride in tap water can be traced back to the early 1900’s when a young dentist named Frederick McKay moved to Colorado Springs to open his first dental practice. One of his first observations upon arriving to Colorado Springs was that a large portion of the local population had unexplained heavy brown stains on their teeth. While the discolored teeth were unsightly, McKay also observed that they were unusually resistant to decay, and set out to figure out the cause. In 1931, after decades of persistent investigation, McKay and his collaborators discovered that the discoloration and resistance to decay were due to unusually high concentrations of fluoride in the local water supply. 

In the 1930’s, water testing methodologies became more sophisticated, which allowed researchers to investigate whether or not there was an "ideal" fluoride concentration in water that was high enough to prevent tooth decay, but not so high that it would cause the unsightly discoloration (also known as mottling). One set of researchers found that a fluoride concentration near one part per million (ppm) seemed to be the “sweet spot” that satisfied both requirements. Fast forward to 1945, and Grand Rapids, MI became the first city to add fluoride to their public water supply with the goal of improving dental health. The measure worked, and cavities in children born after the start of fluoridation dropped by more than 60%. Seventy years later, fluoride remains a major tool used by dentists and the public to combat tooth decay.

While this is certainly a success story, a lot has been learned about dental fluoride treatment since the mid 20th century. For example, we have learned that most of the protection provided by fluoride appears to be topical (a result of the fluoride coming in contact with the tooth itself after it emerges from the gums), rather than sub gum line tooth growth. This means that the anti-decay benefits can be realized by applying it topically (e.g. using toothpaste, mouthwash).

Is Ingesting Fluoride Bad?

While there is near consensus among public health and dental organizations that the population-scale dental benefits of fluoride in tap water outweigh the risks, The World Health Organization, Center for Disease Control, and other organizations agree that some children in North America are getting too much accumulated exposure to fluoride, which can lead to a condition called fluorosis. Although nearly all cases of fluorosis in North America are purely cosmetic, they are problems nonetheless, which has generated discussion about lowering the "ideal" concentration of fluoride in drinking water and/or decreasing the amount of fluoride in children’s toothpaste formulations.

In addition to the problems associated with fluorosis, there is concern among some that fluoride can affect neurological development and function in children. There are, in fact, human studies (mostly Chinese & Indian populations) that have found a correlation between high fluoride exposure and lower IQ. In 2012, a group from The Harvard School of Public Health conducted a meta-analysis (i.e. combining the results of different studies) of all available data, and concluded that “The results support the possibility of an adverse effect of high fluoride exposure on children’s neurological development.” As you might imagine, this conclusion obviously generated a great deal of alarm when framed by the media, and was cited by opponents of fluoridation as proof that adding fluoride to tap water is dangerous. However, when you read the actual study, the group from Harvard also wrote in the same article that each of the original studies “had deficiencies, often very serious ones that limit the conclusions that can be drawn.” Furthermore, when the same authors were interviewed at a later time by the news media, they were quick to point out that the study was not directly applicable to drinking water fluoridation in the US, because the original studies included some subjects from areas where natural fluoride concentrations in drinking water were more than 10 times higher than the concentrations found in North American fluoridated tap water. They argued that a more relevant study would compare subjects whose drinking water had no fluoride to subjects whose water had fluoride levels at or near levels found in fluoridated North American tap water. The ideal study would also use a subject population where other factors that contribute to IQ (e.g. poverty, lead, arsenic) are well-controlled. Since 2012, more studies (with varying research goals) on the topic have been conducted, and the methodologies, results, and conclusions continue to be passionately debated in the context of tap water fluoridation in North America.

Even more recently, tap water fluoridation has been brought forward when a British scientist published the first observational study showing a population-level association between fluoridated tap water and hypothyroidism. However, this study is less than one year old, so it is too recent to follow-on studies or peer-reviewed debate play out in the scientific literature. This is a "stay tuned" situation.

Overall Takeaway on “The Fluoride Controversy”

As we step back from the history and science of tap water fluoridation, we must remember that a number of factors go into shaping public policy, for example balancing individual choice against benefits to the overall population. Proponents of tap water fluoridation are adamant that the dental benefits outweigh the potential health risks, particularly for low income families who may not have access to dental care or products. However, others argue that because dental hygiene and products have improved (e.g. fluoride toothpastes, mouthwash), there is no longer a need to accept any risk associated with ingesting fluoride in drinking water. Still others believe that it is fundamentally inappropriate for municipalities to administer widespread fluoride medical treatments through public water supplies.

Overall, it’s a situation when there are multiple different (but reasonable) viewpoints on the topic, which can be extremely frustrating for anyone who is seeking a definitive black or white answer to guide their lifestyle. It also generates an opportunity for people to present misleading (or fabricated) "data" to sway public opinion. (Just remember, anyone can make a website). If individuals who use fluoride toothpaste and mouthwash decide to purchase a water filter that reduces their exposure to ingested fluoride, we make sure that they are not doing it in response to something they read about government-sponsored public poisoning programs, the "fact" that drinking fluoridated tap water is the same thing as drinking sarin, or out of fear that the reason why tap water fluoridation was invented was to find a profitable use for toxic waste. While those claims would certainly help us sell a lot of custom water filters, they simply are not true.

As always, feel free to drop an email to hello@hydroviv.com.


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