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:

1. This means roughly 10% of Americans are drinking unsafe tap water that doesn’t meet safety guidelines.¹

2. The safety guidelines for drinking water are outdated. The EPA currently only requires municipal water suppliers to monitor for 92 contaminants - when we have hundreds if not thousands in our drinking water now.

Forever chemicals

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

Microplastics

It has also been estimated that between 60-90% of the US tap water contains microplastic, and we all know this is an emerging and important issue now, given how ubiquitously microplastic is found in our bodies. Up until recently, we didn’t know what this meant for our health - but a recent study published in the prestigious New England Journal of Medicine³ showed people with micro- and nano plastics in their arteries had a 4x increased risk of having a heart attack, stroke, and dying from any cause (all cause mortality) - although causation has not been proven, I definitely want to minimize the amount of plastic in my body until we know more.

When it comes to drinking water, we are lucky in that, compared to developing countries, US water is among the safest in the world from a hygiene perspective - but sadly, industrialisation means there are harmful contaminants in our drinking water that threaten our health, even after the water has been treated to adhere to EPA standards. 

---

---

Safe Drinking Water Act - not stringent enough to protect Americans

Water contamination may occur through sewage releases, runoff from crops treated with fertilizer or pesticides, manufacturing practices (e.g. DuPont - if you have not watched Dark Waters, please watch it), poorly maintained distribution systems, old infrastructure like lead or PVC pipes that carry water etc.

In the US, Community water systems must follow the Safe Drinking Water Act, which provides instructions and guidelines for water quality, testing schedules, and testing methods to ensure that the water is ‘safe’.

However, the Safe Drinking Water Act only covers guidelines for 92 chemicals, when in reality, there are hundreds upon thousands of chemicals that may still be contaminating our water without any legal limits or regulations. In fact, these limits may not be strict enough to protect our health - Studies have shown adverse health outcomes from levels of those 92 chemicals way below the EPA’s standards, including links to cancer, hormone disruption, and reproductive and immune system harm⁴ - and that’s IF the municipal water suppliers actually met the standards.

Rule breakers

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 due to a high number of leaks, and the presence of contaminants like lead and PFAs.

The contaminants

This old infrastructure means that, even after being treated and passing safety regulations at the municipal utility, pipe corrosion from distribution systems means there could be contaminats in the drinking water AFTER it leaves the treatment plants.

The EPA estimates that drinking water can make up 20% or more of a person’s exposure to lead, and infants who drink formula can get 40-60% of the lead exposure from tap water. 

The National Toxicology Program has found that exposure to lead during childhood, with even low levels in the blood, is associated with impaired cognitive functioning and academic achievement, as well as increased attention and behavioral issues.⁷ 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.⁸

Arsenic is another toxicant that can be found in water, especially in well-water. The EPA recognizes arsenic as 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.⁹

Other important toxicants in our water:

1. Fluoride may be added to drinking water in an attempt to aid dental health, but few relevant studies exist to support its merit. Now, whether you use fluoride toothpaste is a separate discussion - it CAN help reduce cavities, however, not everyone needs it. So that’s something for you and your dentist to discuss. However, there is no need for fluoride to be ingested - in fact, it can cause fluorosis in excess. THe US Public Health Service currently recommends fluoride levels of 0.7mg/L in drinking water. The National Toxicology Program recently sounded the alarm for children’s IQ at 1.5mg/L¹⁰ - and 2 million Americans are exposed to this level of higher via their drinking water. Even if the water is checked and treated to adhere to current standards for fluoride, there are studies to show it can still impair thyroid function.¹¹ , damage to liver and kidney functions in children, and high prenatal exposure to fluoride has been associated with impaired cognitive functioning and lower IQ scores at the age of 4 and again between 6-12 years old.¹² ¹³

• 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.¹⁴ ¹⁵It can be a risk factor for thyroid disorders among children and pregnant women.¹⁶

• 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.¹⁷ ¹⁸¹⁹²⁰Animal studies have suggested even more drastic potential, with a study by UC Berkeley showing that exposure to atrazine could turn male frogs into females.²¹

• 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.²²²³²⁴ Pregnant 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 for those babies later in life.²⁵

  Exposure to 49 mcg/L of trihalomethanes (THM) in drinking water had a twofold increase in bladder cancer risk compared to those with levels at or below 8 mcg/L.

  Moreover, these compounds can be inhaled, and those taking long showers (>15min) in chlorinated water with high THM had an 83% increased risk of bladder cancer compared to the lowest (so a shower filter is important!)²⁶

The list doens’t end here - there are many others, such as perchlorate, BPA, other chemical compounds from personal care products, and even 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!

Ok, but I don’t drink tap - I buy bottled water!

Sadly, bottled water is not well regulated, and studies have shown that it can contain MORE MICROPLASTICS than tap.

If you do use a water delivery service, be sure to ask for a testing report and see if the water can be delivered in glass instead of plastic. I often see big plastic water jugs sitting outside homes in direct sun and heat - which both increase the leaching of endocrine disrupters and micro-/nanoplastics 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 at home. 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

The first step is to know what is in your tap water.

The next step is to find a filter that’s been TESTED and shown to remove these contaminants.

If you are in the US, you can look up your tap water report here.

3 main types of water filters:

1. Activated Carbon/Gravity filters - are the most common 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, and 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 the filter can remove - the smaller, the better, and the CDC recommends a minimum of 1 micron.  Some carbon filters 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 - ask for testing reports and make sure it’s been tested to NSF standards!! - it’s the ONLY way to know if they are effective.

2. Reverse osmosis water filters - are generally the most effective at contaminant removal because good ones can remove just about everything out of the water - including helpful minerals. They work by forcing water through a semi-permeable membrane, and most also have a carbon filter too. This process also wastes a lot of water. Usually, for every 1 L of clean water you get, you need to use 4-5 L of water. I live in California, where water is revered - and this is one of the reasons I switched from RO to a different system.

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 but do not really remove any other contaminants. These are often used in whole-house filters - which I consider only sufficient for bathing and showering. I would not rely on a whole-house filter to provide me with the cleanest drinking water.

So, to recap:

• Reverse Osmosis is the most robust at removing contaminants. However, the downside is that it also removes beneficial minerals and wastes a lot of water. You may not need this if your municipal water is pretty clean.

• Activated carbon filters can range from simple refrigerator filters, which are usually only good for improving the taste (i.e., removing chlorine) but do not really remove much in terms of other contaminants. There are some block carbon pitcher filters that perform almost as well as reverse osmosis, and you should ask for testing reports and ensure they test to NSF standards.

• Whole house filters are great for baths and showers. You’d still need to install a more robust filter for drinking water even if you have a whole house water filter.

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.

Which filter is BEST?

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 has been NSF-certified and 3rd party tested to remove the contaminants found in your drinking water (see how to test below).

If you can’t do that, then you should look up your tap water report here, and then pick a filter that’s been NSF tested to remove the contaminants in your water.

I look for NSF testing by one of the official certifying bodies e.g. IAPMO, because it is more rigorous and, whilst not perfect, better than consumer-generated 'review' videos that are wildly inaccurate - social media reviews are NOT what you should be using to guide your choices.

What I use in my home right now

I had a multi-stage non-reverse osmosis filter under the sink unit; however, this company changed ownership, and I could taste the chlorine in my water after just 6 months of changing filters, so I switched to the Smartshield (code: platefulhealth for 20% off) recently and am very happy with it so far.

It has been certified to NSF standards 42, 53, and 401 by IAPMO. The testing reports show it can remove the contaminants in MY tap water. Now, this may not be the best choice for YOU - you need to see what’s in your water first.

Other options: 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 do not like their alkali or Wifi options)

RO 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 it can be remedied by adding minerals back. However, a lot of companies tack on an ‘extra’ filter that re-mineralizes the water, and this usually has NO testing, so I’m not a fan and have asked Aquatru to remove their ‘alkali’ water filters from my affiliate page for that reason.

When I did use reverse osmosis, I went with something that has been 3rd party tested - like Concentrace by Trace Minerals (though I have not looked at their testing report in a couple of years, since I stopped using RO).

What about the pitcher-style filters? 

They can be effective provided they have been tested to NSF standards! Ignore social media influencers telling you that pitchers are no good - this is a gross generalization. Not all pitchers are the same. Some can be great.

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).

I use the Epic Water  (affiliate discount code: platefulhealth for 20% off) - because they were more transparent than the other popular pitcher brands.

---

HOW TO TEST YOUR WATER

I recommend my clients test their tap water when testing is within their budget.

If you have a well, or if you want to look for contaminants NOT included in the 92 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.

1. US Centers for Disease Control and Prevention, Importance of Water Quality and Testing,<https://www.cdc.gov/healthywater/drinking/public/water_quality.html>, accessed Jan 29th 2024

2. Smalling KL, Romanok KM, Bradley PM, Morriss MC, Gray JL, Kanagy LK, Gordon SE, Williams BM, Breitmeyer SE, Jones DK, DeCicco LA, Eagles-Smith CA, Wagner T. Per- and polyfluoroalkyl substances (PFAS) in United States tapwater: Comparison of underserved private-well and public-supply exposures and associated health implications. Environ Int. 2023 Aug;178:108033. doi: 10.1016/j.envint.2023.108033. Epub 2023 Jun 17. PMID: 37356308.

3. Marfella R, Prattichizzo F, Sardu C, Fulgenzi G, Graciotti L, Spadoni T, D'Onofrio N, Scisciola L, La Grotta R, Frigé C, Pellegrini V, Municinò M, Siniscalchi M, Spinetti F, Vigliotti G, Vecchione C, Carrizzo A, Accarino G, Squillante A, Spaziano G, Mirra D, Esposito R, Altieri S, Falco G, Fenti A, Galoppo S, Canzano S, Sasso FC, Matacchione G, Olivieri F, Ferraraccio F, Panarese I, Paolisso P, Barbato E, Lubritto C, Balestrieri ML, Mauro C, Caballero AE, Rajagopalan S, Ceriello A, D'Agostino B, Iovino P, Paolisso G. Microplastics and Nanoplastics in Atheromas and Cardiovascular Events. N Engl J Med. 2024 Mar 7;390(10):900-910. doi: 10.1056/NEJMoa2309822. PMID: 38446676; PMCID: PMC11009876.

4. Environmental Working Group, No-Compromise Benchmarks to Fully Protect Public Health, <https://www.ewg.org/sites/default/files/u352/EWG_TWDBStandards-Chart_PP01.pdf?_ga=2.28689916.1564802286.1609221307-566226115.1605306172>, accessed Jan 29th 2024

5. New York Times, Millions in U.S. Drink Contaminated Water, <https://www.nytimes.com/2009/12/08/business/energy-environment/08water.html?_r=0>, accessed Jan 29th 2024

6. Stoiber, T., Temkin, A., Andrews, D. et al. Applying a cumulative risk framework to drinking water assessment: a commentary. Environ Health 18, 37 (2019). https://doi.org/10.1186/s12940-019-0475-5

7. National Toxicology Program, Health Effects of Low Level Lead, <https://ntp.niehs.nih.gov/sites/default/files/ntp/ohat/lead/final/monographhealtheffectslowlevellead_newissn_508.pdf>, accessed Jan 29th 2024

8. Reuben A, Caspi A, Belsky DW, et al. Association of Childhood Blood Lead Levels With Cognitive Function and Socioeconomic Status at Age 38 Years and With IQ Change and Socioeconomic Mobility Between Childhood and Adulthood. JAMA. 2017;317(12):1244–1251. doi:10.1001/jama.2017.1712

9. Smith AH, Marshall G, Yuan Y, Ferreccio C, Liaw J, von Ehrenstein O, Steinmaus C, Bates MN, Selvin S. Increased mortality from lung cancer and bronchiectasis in young adults after exposure to arsenic in utero and in early childhood. Environ Health Perspect. 2006 Aug;114(8):1293-6. doi: 10.1289/ehp.8832. PMID: 16882542; PMCID: PMC1551995.

10. https://ntp.niehs.nih.gov/whatwestudy/assessments/noncancer/completed/fluoride

11. Kheradpisheh Z, Mirzaei M, Mahvi AH, Mokhtari M, Azizi R, Fallahzadeh H, Ehrampoush MH. Impact of Drinking Water Fluoride on Human Thyroid Hormones: A Case- Control Study. Sci Rep. 2018 Feb 8;8(1):2674. doi: 10.1038/s41598-018-20696-4. PMID: 29422493; PMCID: PMC5805681.

12. Xiong X, Liu J, He W, Xia T, He P, Chen X, Yang K, Wang A. Dose-effect relationship between drinking water fluoride levels and damage to liver and kidney functions in children. Environ Res. 2007 Jan;103(1):112-6. doi: 10.1016/j.envres.2006.05.008. Epub 2006 Jul 10. PMID: 16834990.

13. Bashash M, Thomas D, Hu H, Martinez-Mier EA, Sanchez BN, Basu N, Peterson KE, Ettinger AS, Wright R, Zhang Z, Liu Y, Schnaas L, Mercado-García A, Téllez-Rojo MM, Hernández-Avila M. Prenatal Fluoride Exposure and Cognitive Outcomes in Children at 4 and 6-12 Years of Age in Mexico. Environ Health Perspect. 2017 Sep 19;125(9):097017. doi: 10.1289/EHP655. PMID: 28937959; PMCID: PMC5915186.

14. Gupta SK, Gupta RC, Seth AK, Gupta AB, Bassin JK, Gupta A. Methaemoglobinaemia in areas with high nitrate concentration in drinking water. Natl Med J India. 2000 Mar-Apr;13(2):58-61. PMID: 10835850.

15. Knobeloch L, Salna B, Hogan A, Postle J, Anderson H. Blue babies and nitrate-contaminated well water. Environ Health Perspect. 2000 Jul;108(7):675-8. doi: 10.1289/ehp.00108675. PMID: 10903623; PMCID: PMC1638204.

16. Gatseva PD, Argirova MD. High-nitrate levels in drinking water may be a risk factor for thyroid dysfunction in children and pregnant women living in rural Bulgarian areas. Int J Hyg Environ Health. 2008 Oct;211(5-6):555-9. doi: 10.1016/j.ijheh.2007.10.002. Epub 2007 Dec 27. PMID: 18164247.

17. Chevrier C, Limon G, Monfort C, Rouget F, Garlantézec R, Petit C, Durand G, Cordier S. Urinary biomarkers of prenatal atrazine exposure and adverse birth outcomes in the PELAGIE birth cohort. Environ Health Perspect. 2011 Jul;119(7):1034-41. doi: 10.1289/ehp.1002775. Epub 2011 Mar 2. PMID: 21367690; PMCID: PMC3222984.

18. Chevrier C, Limon G, Monfort C, Rouget F, Garlantézec R, Petit C, Durand G, Cordier S. Urinary biomarkers of prenatal atrazine exposure and adverse birth outcomes in the PELAGIE birth cohort. Environ Health Perspect. 2011 Jul;119(7):1034-41. doi: 10.1289/ehp.1002775. Epub 2011 Mar 2. PMID: 21367690; PMCID: PMC3222984.

19. Munger R, Isacson P, Hu S, Burns T, Hanson J, Lynch CF, Cherryholmes K, Van Dorpe P, Hausler WJ Jr. Intrauterine growth retardation in Iowa communities with herbicide-contaminated drinking water supplies. Environ Health Perspect. 1997 Mar;105(3):308-14. doi: 10.1289/ehp.97105308. Erratum in: Environ Health Perspect 1997 Jun;105(6):570. PMID: 9171992; PMCID: PMC1470002.

20. Ochoa-Acuña H, Frankenberger J, Hahn L, Carbajo C. Drinking-water herbicide exposure in Indiana and prevalence of small-for-gestational-age and preterm delivery. Environ Health Perspect. 2009 Oct;117(10):1619-24. doi: 10.1289/ehp.0900784. Epub 2009 Jul 31. PMID: 20019915; PMCID: PMC2790519.

21. Berkley News, Pesticide atrazine can turn male frogs into females, <https://news.berkeley.edu/2010/03/01/frogs/>, accessed Jan 29th 2024

22. Villanueva CM, Cantor KP, Cordier S, Jaakkola JJ, King WD, Lynch CF, Porru S, Kogevinas M. Disinfection byproducts and bladder cancer: a pooled analysis. Epidemiology. 2004 May;15(3):357-67. doi: 10.1097/01.ede.0000121380.02594.fc. PMID: 15097021.

23. Colman J, Rice GE, Wright JM, Hunter ES 3rd, Teuschler LK, Lipscomb JC, Hertzberg RC, Simmons JE, Fransen M, Osier M, Narotsky MG. Identification of developmentally toxic drinking water disinfection byproducts and evaluation of data relevant to mode of action. Toxicol Appl Pharmacol. 2011 Jul 15;254(2):100-26. doi: 10.1016/j.taap.2011.02.002. Epub 2011 Feb 4. PMID: 21296098.

24. Bove F, Shim Y, Zeitz P. Drinking water contaminants and adverse pregnancy outcomes: a review. Environ Health Perspect. 2002 Feb;110 Suppl 1(Suppl 1):61-74. doi: 10.1289/ehp.02110s161. PMID: 11834464; PMCID: PMC1241148.

25. Säve-Söderbergh M, Toljander J, Donat-Vargas C, Berglund M, Åkesson A. Exposure to Drinking Water Chlorination by-Products and Fetal Growth and Prematurity: A Nationwide Register-Based Prospective Study. Environ Health Perspect. 2020 May;128(5):57006. doi: 10.1289/EHP6012. Epub 2020 May 18. PMID: 32438832; PMCID: PMC7263457.

26. Villanueva CM, Cantor KP, Grimalt JO, Malats N, Silverman D, Tardon A, Garcia-Closas R, Serra C, Carrato A, Castaño-Vinyals G, Marcos R, Rothman N, Real FX, Dosemeci M, Kogevinas M. Bladder cancer and exposure to water disinfection by-products through ingestion, bathing, showering, and swimming in pools. Am J Epidemiol. 2007 Jan 15;165(2):148-56. doi: 10.1093/aje/kwj364. Epub 2006 Nov 1. PMID: 17079692.