What's in your tap water? How to pick a water filter

Almost 50% of tap water in the US is contaminated with PFAs (forever chemicals), not to mention pesticides, pharmaceutical medications, microplastics. Learn how to protect you and your family...

Your tap water may not be as clean as you think.

While the CDC cites that the tap water for over 90% of Americans comes from community systems that follow 'safe drinking standards', there are two problems: firstly, that means that roughly 10% of Americans are drinking unsafe tap water that doesn’t meet safety guidelines.¹ Secondly, the safety guidelines for drinking water are outdated and do not actually follow the science - rather, they are influenced by politics and how much it'll cost to meet the standards. 

A recent study showed that almost 50% of the tap water tested in the US were contaminated with a forever chemical from the PFAs family - these chemicals have been linked to fertility issues, pregnancy complications, thyroid disease, certain cancers, weight gain - and more!² 

We are lucky in that, compared to developing countries, US water is among the safest in the world - but 7.2 million Americans still get sick every year from waterborne diseases.³

In addition, evidence shows there are harmful contaminants in our drinking water that threaten our health, even after the water is treated to adhere to EPA standards. 

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Water contamination may occur through sewage releases, natural chemicals and minerals like arsenic, runoff from crops treated with fertilizer or pesticides, manufacturing practices, improper treatment of the water, poorly maintained distribution systems, etc. For these reasons, the EPA has designed regulations that drinking water in the US is required to meet. Community water systems must follow the Safe Drinking Water Act, which provides instructions and guidelines for water quality, testing schedules, and testing methods ensure that the water is safe. However, the Safe Drinking Water Act only covers guidelines for 91 chemicals, when in reality, there are thousands upon thousands of chemicals that may still be contaminating our water without any legal limits or regulations. Studies also show adverse health outcomes from levels of those 91 chemicals way below the EPA’s standards, including links to cancer, hormone disruption, and reproductive and immune system harm.⁴ This suggests the legal limits may not be strict enough to ensure safety. 

The US has never had perfectly safe water systems. The New York Times reported that nearly 50 million people between 2004 and 2009 consumed water that contained illegal concentrations of contaminants that did not adhere to the EPA’s guidelines.⁵ In 2017, the state of California had over 300 water systems that were not in compliance with safe drinking water standards, and an estimated 15,500 cases of cancer in California could occur within 70 years just because of unsafe drinking water.⁶ Just a few years ago, the American Society of Civil Engineers gave the US a D grade for our drinking water delivery system, which is hardly a passing grade due to a high number of leaks and the presence of contaminants like lead and PFA. Most recently, as of July 2020, there are 2,230 water system locations in 49 different states across the country that have proven to be contaminated with PFAS, synthetic chemicals which have been associated with immunodeficiencies and cancer.⁷ 

The EPA cites frequent contaminants to be microorganisms (bacteria such as E. coli and noroviruses), inorganic chemicals (including lead, arsenic, fluoride, nitrates, and nitrites), organic chemicals (including atrazine, glyphosate, trichloroethylene, and tetrachloroethylene), and disinfection byproducts (such as chloroform).⁸ 

• Heavy metals, such as lead, can be found in drinking water even after being treated and passed safety regulations due to corrosion of pipes from distribution systems. The EPA estimates that drinking water can make up 20% or more of a person’s exposure to lead, and infants who drink formulas can get 40-60% of the lead exposure from tap water. 

Exposure to lead from drinking water raises lead levels in the blood, resulting in an array of respiratory, gastrointestinal, and potentially cardiovascular health issues.⁹ The National Toxicology Program has found that exposure to lead during childhood, with in even low levels in the blood, is associated with impaired cognitive functioning and academic achievement, as well as increased attention and behavioral issues.¹⁰ Other studies have also found childhood lead exposure was associated with lower cognitive functioning and socioeconomic status in adulthood. Greater exposure correlated with a greater decline in IQ from childhood to adulthood.¹¹

Arsenic is another toxin that can be found in water. The EPA recognizes a carcinogen associated with many forms of cancer, adverse cardiovascular, pulmonary, immunological, neurological, and endocrine effects, and increased mortality and morbidity if exposed during prenatal development or childhood.¹²

Other toxins found in our water includes:

1. Fluoride is another major inorganic offender in drinking water. Fluoride may be added to drinking water in an attempt to reduce social inequalities in dental health, but few relevant studies exist to support its merit. Even if the water is checked and treated to adhere to current EPA standards for fluoride, it can still impair thyroid function.¹³ Fluoride has also been found to cause damage to liver and kidney functions in children, even at low levels, and high prenatal exposure to fluoride is associated with impaired cognitive functioning and lower IQ scores at the age of 4 and again between 6-12 years old.¹⁴ ¹⁵

• Nitrates and nitrites from fertilizer, livestock manure, and human sewage systems can infect groundwater sources of drinking water. High levels can contribute to blood disorders, even turning babies blue if they consume such water with their formula.¹⁶ ¹⁷It can be a risk factor for thyroid disorders among children and pregnant women.¹⁸

• Pesticides like atrazine and glyphosate are two of the most popular agricultural pesticides in the US. EWG investigation has suggested that atrazine disrupts hormones that could be particularly harmful to developing fetuses, which has been supported by epidemiological studies showing an association between prenatal exposure to atrazine and reduced fetal development, including a small head circumference and restricted growth, prematurity, and low birth weight for babies whose pregnant mothers consumed atrazine in their drinking water.¹⁹ ²⁰²¹²²Animal studies have suggested even more drastic potential, with a study by UC Berkeley showing that exposure to atrazine could turn male frogs into females.²³

• Disinfection byproducts occur when disinfectants, such as chlorine and chloramine, are added to drinking water to kill microbial contaminants. They react with organic matter in the water to form byproducts, such as chloroform (one of the common trihalomethanes). Drinking water with high levels of these byproducts has been associated with an increased risk of bladder cancer and several reproductive and developmental effects.²⁴²⁵²⁶Pregnant women exposed to or consumed even low levels of disinfection byproducts have a greater risk of giving birth to small and underweight babies, which is associated with a slew of high-risk factors and chronic health issues those babies later in life.²⁷ For everyone, exposure to water with chlorine in it, either from drinking it or taking showers in it, has been associated with a twofold risk of bladder cancer.²⁸

These are just a few of the most common contaminants that can be found in your drinking water and the reported associated health effects. However, many others, such as manganese, perchlorate, PFAS, BPA, and other chemical compounds from personal care products, and pharmaceuticals. All of these toxins and chemicals can still be found in your drinking water even after it has been tested, treated, and approved by EPA regulations because the utilities are not required to test for them! Water contamination and how the water is treated depend on the source and the volume - some sources are more susceptible to contamination than others. It can remain contaminated all the way through the faucet, into your cup, and into your body. 

Bottled water is not well regulated, and consumer studies have shown some are no better than tap. If you do use a water delivery service, be sure to ask for a testing report. The other thing to consider is the water often sits in plastic containers for weeks/months, sometimes in heat or direct sunlight during delivery & transportation, which increases the leaching of endocrine disrupters from the plastic into the water. 

The Solution

The best way to ensure that your drinking water is actually safe for you to consume is to invest in an effective water filter. In my opinion, this works out cheaper than getting bottled water in the long run.

There are many different types of water filters, and they all work differently. It can be confusing, so keep reading along as I break it down for you.

HOW TO LOOK FOR A GOOD WATER FILTER

There are three basic types of water filters: carbon filtration, reverse osmosis, and ion exchange. There are many brands on the market, and there is no ‘one size fits all’ I’m afraid.

I can share what works well for my family and me, but it may not suit you - how a filter performs depends on so many factors, for example, your water pH, flow speed.. etc.

1. Activated Carbon filtration filters are the commonest and cheapest. They are used in 'most' pitcher, refrigerator or faucet water filters. They can use either a carbon block or granulated activated carbon, which binds to contaminants in the water and traps them in the filter as the water moves through. How it works is in the name: granulated is made up of small carbon granules, block is made up of a block of carbon. This type of filter varies widely in efficacy determined by the size of particles they can remove. Generally block carbon filters are more robust but may have a slower filtration rate so when you are shopping, look for the particle size th filter can remove - the smaller the better, and the CDC recommends a minimum of 1 micron.  Some only decrease the amount of chlorine and help your water taste better, while others can reduce contaminants such as asbestos, VOCs, PCBs, some pesticides and prescription medications. However, they usually do not remove any inorganic pollutants like arsenic, mercury, fluoride, nitrates, chloramine, bacteria.

2. Reverse osmosis water filters are what the EWG thinks (and I agree) is generally the most effective because they literally can remove just about everything out of the water. They work by forcing water through a semi-permeable membrane, and most also have a carbon filter too. So, in terms of contaminant removal, RO’s are the holy grail. However, this process wastes a lot of water, and another drawback is that this treatment also removes minerals like iron, calcium, and magnesium, so you may have to add back some minerals into your water, especially if your diet is lacking in mineral-rich foods like vegetables (discuss this with your dietician or doctor).

3. Ion exchange filters are known as water softeners, and they are potentially the least beneficial, as they only work to reduce minerals like calcium and magnesium, which improve the taste of water and are also beneficial for your health, but that can build up in plumbing, but do not really remove any other contaminants. These are often used in whole house filters and may leave the water higher in sodium - be careful with these if you've been advised to follow a low sodium diet. 

There are also distillation water filters that vaporize water into steam and then condense it back down. This process also removes minerals and bacteria, viruses, and chemicals that have a higher boiling point than water. However, it leaves chlorine, VOCs, and other chemicals in the water.

Whole-house filters are also another option, which filters all of the water into your house, not just your tap water. This system is expensive compared to other filters and removes chlorine from all water going throughout your house but is not as robust at removing other common contaminants. Hence, you still need a separate filter for your drinking water ideally even if you have a whole-house system.

Overall, there is no one best water filter system - it is not a “one size fits all” type of industry or investment. It would be best to look for filters for specific contaminants based on where you live and choose one certified by a third party to reduce or remove those specific contaminants effectively. A helpful guide is the EWG’s Tap Water Database, which uses data from nearly 50,000 local utilities in 50 states to provide you with a list of contaminants found in your local drinking water that is coming through your tap so that you know what your filter needs to remove - they also make recommendations on what type of filter is capable of removing contaminants in your water. So definitely check that out. 

Which filter is BEST?

As I said, there IS NO PERFECT water filter that suits everyone.

In an ideal world, you would test your tap water first and then choose the one that is best for your tap water (see how to test below)

I cannot recommend one 'best water filter' for you, because I don't know your unique circumstances, I can only share what I personally use - this may or may not be suitable for you. There are so many units out there and a ton of amateur consumer testing videos on the internet, that are not reliable sources of information.

I look for NSF testing, because it is more rigorous, and whilst not perfect, better than consumer-generated 'review' videos that are prone to testing inaccuracies. 

Option 1: Under sink and whole house:

I have a non-reverse osmosis filter undersink unit; however, this company changed ownership, and now I am unsure I will continue to recommend them. When choosing one for yourself, remember that there is no perfect filter, and there are a lot of variables involved, e.g. flow rate, locality, etc. 

The most robust type of water filter is going to be Reverse Osmosis - however, this can waste a lot of water (for every 1 L of filtered water, you need about 4-5L of water)

It strips the water of helpful minerals. Now, this may or may not be a concern for you, depending on your diet, activity level, and where you live. And can be easily remedied by adding minerals back - like Concentrace by Trace Minerals. Whether you need this, and how much you need is a question for your doctor.  I also make a lot of herbal infusions e.g. with nettle, oatstraw, which are naturally rich in minerals, so I didn’t always use Concentrace.

Option 2: Countertop Reverse Osmosis 

Now, if you cannot get an under-sink unit, a countertop RO might be a good option and that’s what I used up until I got my under-sink unit. 

This is what I used to use and loved, and you can get $100 off via my affiliate link.

I sometimes added this mineral drop back into my water (make sure to check with your doctor first! This is not medical advice and I cannot tell you if this is suitable for you or how much you need - it depends on your diet, activity level, age, toxicity level, etc. ). 

What about the pitcher style filters? 

They are definitely better than nothing and a great starting point if you cannot afford a more advanced filter system (sorry, fridge filters are really not effective) #dowhatyoucan - every little step can make a big difference! 

That said, most are not tested to NSF standards, or if they are, not in NSF-certified labs (which I understand, it is VERY expensive to test in these facilities). As such, I only use these when I travel. 

I use Epic Water  (affiliate discount code: platefulhealth for 20% off) - because they were more transparent than the other popular pitcher brands other influencers promote (that brand may be good, but since I don’t understand the technology and they were not transparent, I decided not to use theirs). 

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HOW TO TEST YOUR WATER

I recommend my clients where testing is in their budget to test their water first and then find the best filter depending on what the test shows. 

If you have a well, or if you want to look for contaminants NOT included in the 91 chemicals currently monitored for by your water utilities, then you can either look for a state-certified lab via the EPA or use Tap Score - Founded in conjunction with The University of California in Berkeley and the Boston University School of Public Health, the tests are performed with EPA, ASTM methods.  Based on the contaminants they find, they will recommend types of NSF-certified filters to remove them - this is a great way to find the best water filter for you. 

I have an affiliate discount code: Platefulhealth for $10 off.  

I'm an affiliate for some of the products linked on my website. I get asked about products I use and love all the time, and by being an affiliate, I can negotiate discount codes to share with you, plus earn a small commission if you use my code or link to purchase. This helps me to support my research so that I can continue to provide the content on my platform, thank you so much for your support.

Originally written Jan 29th 2024

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