Making Aluminum and Fluoride Free Drinking Water

In the U.S. both fluoride and aluminum are intentionally added to drinking water by some community water departments. These chemicals are both individually harmful and combined they react to make very toxic molecules. For this reason I recommend they be filtered out of drinking water:

·         Fluoride (i.e. sodium fluoride, sodium fluorosilicic acid, or fluorosilicic acid) is added to drinking water in order to lower the incidence of dental caries particularly in children, while efficacy of supplemental fluoride for adults has not been established.  Water fluoridation reduces cavities in children by 35% in baby teeth and 26% in permanent teeth¹. The U.S. Department of Health and Human Services (HHS) and the U.S. Environmental Protection Agency (EPA) in 2011 recommended adding fluoride to adjust the level of drinking water to 700mcg/liter². The U.S. environmental protection agency (EPA) currently has set a secondary non-enforceable maximum secondary standard (SMCL) for fluoride in drinking water at 2,000mcg/liter (equivalent to 2ppm)³.

·         Aluminum (i.e. alum) is added to drinking water in order to precipitate and coagulate impurities in surface waters so these impurities can be removed.  This process leaves residual aluminum in drinking water at an average level of 179mcg/liter as found in a survey of 380 U.S. community water supplies⁴. Aluminum in drinking water greater than 100mcg/liter increases the risk of Alzheimer’s disease⁵ and higher than normal levels of aluminum have been found in brains of those diagnosed with both sporadic and familial Alzheimer’s^6,7. Aluminum has also been found at higher than normal levels in the brains of children with autism⁸. Research data now indicates that aluminum accumulation is likely a causal factor of both Alzheimer’s and autism⁵.

The U.S. environmental protection agency (EPA currently has set a secondary non-enforceable maximum secondary standard (SMCL) for aluminum in drinking water at 50 to 200mcg/liter³.

·         Combination of Aluminum and Fluoride: Aluminum accumulates in the brain and the rate of accumulation is doubled by fluoride^6,9.  By adding the EPA’s maximum safe level of fluoride (2,000ppm) to drinking water doubles the rate of aluminum accumulation in the rat brain⁹. This may be due to both fluoride and aluminum ions having an affinity for each other forming a bond that is extremely strong and highly stable in vivo^10,11. A micro molar concentration of aluminum of only 27mcg/liter (i.e. 27ppb) in the presence of excess fluoride results in the formation of aluminum tetrafluoride anions¹². These ions are known mimics of phosphate anions and influence the activity of ATP and GTP phosphoryhydrolases and phospholipase D (PLD)^13,14. These enzymes are involved in metabolism, growth, and differentiation in the body¹³.  An epidemiology study in China has shown that combined high aluminum and fluoride in drinking water coincides with a lower IQ in children aged 8 to 12^15,16. Aluminum accumulation in the brain can be reversed by drinking orthosilicic acid (OSA) rich drinking water¹⁷.

Fluoride not only increases aluminum accumulation, influences the activity of key enzymes, and lowers the IQ of children it also causes darkening of teeth (i.e. dental fluorosis). If you notice mottled enamel on your teeth or your children’s teeth there may be too much fluoride in your drinking water. In addition the efficacy of supplemental fluoride for adults has not been established. If you feel fluoride is not helping you or your family’s health or your children’s IQ, you can remove both fluoride and aluminum from drinking water.

How Best to Remove Fluoride and Aluminum from your Drinking Water

Aluminum Removal: Aluminum is a positively charged ion called a cation that has a high affinity for filters containing a cation exchange resin.  In addition, aluminum can be removed by reverse osmosis (RO) and by distillation. The primary advantages of using cation exchange to remove aluminum are:

·         Essential cations are partially removed and essential anions (i.e. OSA) are not removed¹⁹

·         Low cost filters, such as the Brita pitcher style filter, remove 98.5% of aluminum¹⁹

These two advantages are not shared by RO and distillation that both remove almost all essential trace elements and are higher priced than pitcher style filters, such as Brita and Zero.

Fluoride Removal: Fluoride is a negatively charged anion that has a high affinity for both anion exchange resins and bone char.  In addition, fluoride can be removed by reverse osmosis (RO) and by distillation. The primary advantages of using bone char to remove fluoride are:

·         Essential anions, such as OSA, and essential cations are not removed

·         Bone char is biochar made by heating bones at high temperature and is inexpensive

These two advantages are not shared by anion exchange resins, RO, and distillation. However, bone char filters only have a high capacity for fluoride between pH 3 to 4.  As the pH increases above this range the bone char filters must be replaced more often increasing their operational cost. The alternative to bone char is anion exchange resins that are expensive. For instance, Amberlite IRA-410 anion exchange resin that removes fluoride as effectively as bone char currently sells for $43 a pound while bone-char sells for $8.23 a pound, both in 6 pound quantities. This factor of five difference in price makes bone char fluoride filters preferred over fluoride filters that use an anion exchange resin, such as the Zero filter.

For optimal palatability the total dissolved solids (TDS) in drinking water should be 300ppm or less. Optimal drinking water can be easily adjusted to pH 3 to 4 by adding a 1/8^th of a teaspoon (i.e. a dash) of sodium bisulfate to a gallon of drinking water prior to filtering through a bone char filter and pH readjustment after filtration.  If your drinking water has a TDS higher than 200, the pH may not easily be adjusted to 3 to 4 due to carbonate buffering.  Under this condition anion exchange, RO, or distillation may have to be used to remove aluminum, fluoride, and all essential trace elements from drinking water.  

Essential Trace Elements in Drinking Water

The following table lists the essential trace elements in drinking water that are partially removed by the Brita filter and almost totally removed by the Zero filter, distillation, and reverse osmosis (RO).  Some of these trace elements could be selectively added back to the water after filtration.    

Avoid companies selling mineral additives for drinking water that do not analyze for aluminum, fluoride, and other toxic ions in their products. Don’t add back the toxic chemicals that filtration has removed.

Recommended Aluminum Filter: Brita Pitcher Style Ion Exchange Filters

Aluminum and fluoride are neurotoxic. Since aluminum has no health benefit, unlike fluoride, it is recommended to at least remove aluminum from drinking water.  This can be easily done with a cation exchange filter, such as the Brita pitcher style filter OB03, that removes 98.5% of the aluminum in drinking water at pH 4 to 5.5 but does not remove the anions, such as OSA¹⁹. Note that this has been tested and works in water also containing 700mcg per liter of fluoride²⁰.  One advantage of the Brita filter over other filters, such as a Zero filter, is it only partially removes essential ions from drinking water, such as calcium, magnesium, boron, iron, potassium, manganese, selenium, sodium, zinc, and silicon as OSA²¹.  

The Water Quality Association (WQA) has tested Brita filters for meeting the NSF/ANSI Standards 53 for the removal of copper, lead, and mercury^22,23.  Brita filters have been shown to also reduce the calcium and magnesium in drinking water by 68%²¹.  Brita manufactures two filters:

·         Standard Filter OB03 – filters 40 gallons and lasts for 2-3 months for an average family

·         Longlast Filter OB06 – filters 100 gallons and lasts for 6 months for an average family

The WQA approved performance data sheets for these products are in the following table^22,23.    

The Brita replacement standard filter OB03 and Longlast filter OB06 currently sell for $5 and $15 each respectively on Amazon. Therefore the cost of water filtered by the OB03 and OB06 is approximately 12.5 cents and 15 cents a gallon respectively. The Brita pitcher style filters are recommended as they are affordable and only remove toxic trace elements from drinking water leaving the essential trace elements such silicon as OSA in drinking water.

Recommended Fluoride Filter: Homemade DIY Bone Char Filters

A filter that removes just fluoride and some trace organic impurities but not essential trace elements would be preferred. Such a filter has been made by using bone char.  Bone char is biochar made by heating bones to high temperatures (i.e. 800^oC to 900^oC) in oxygen deficient atmosphere. Biochars made from other organic products, such as coconut shells, are called activated carbon and they have approximately 36 times lower absorption capacities for fluoride than bone char.  

Fluoride Capacity of Bone Char: Bone char filters have been evaluated for fluoride removal capacity from drinking water by several groups^24,25.  The total amount of fluoride removed by bone char is dependent upon the pH of the water being filtered. Maximum fluoride adsorption capacity is at pH 3 but declines by 20 fold as the pH is ramped up to pH 12²⁴. At pH 3 bone char has an adsorption capacity for fluoride that is 2.8 times greater than commercial activated alumina and 36 times greater than commercial activated carbon²⁴.  For the user of a bone char filter it requires acidifying water to pH 3-4 before filtering and then readjusting the pH to 6.3-8.5 after filtering to make the water drinkable.

At pH 7.84 bone char’s limitation is capacity as it can only absorb 0.43mg of fluoride per gram of bone char until its absorption efficiency drops below 90%.  For instance a 200 gram bone char filter lowers the fluoride in 36 gallons of 0.7ppm fluoride in tap water at pH 7.84 to 0.05ppm before the filter removes less than 90%. If this same experiment was carried out at pH 3-4 then a 200 gram bone char filter would lower the fluoride in 360 gallons of 0.7ppm fluoride in water to 0.05ppm before the filter removes less than 90%. 

Fluoride Removal Efficiency of Bone Char: The water being filtered must be in contact with bone char for a minimum required time in order to remove a high percentage of fluoride. This lack of contact time is the reason most commercially available bone char filters are not effective at removing fluoride.  Empty bed contact time (EBCT) is the time period in which water comes in contact with the filtering media (i.e. bone char). EBCT is calculated by dividing the volume occupied by the filtering media by water flow rate through the filter.  For bone char the optimum EBCT is 30 seconds or more²⁶. An example of a bone char filter with an EBCT of 30 is 300cc of filter media with a water flow rate of 10cc/sec or 0.6 liter per min.

How to Make a DIY Homemade Bone Char Filter: Commercial bone char filters are expensive and do not work well, but an efficient bone char filter can be inexpensively assembled from readily available components and refilled with fresh bone char periodically. The cost of components for the do it yourself (DIY) homemade bone char filter is approximately $100 including shipping and the $4.67 cost of bone char. The best source of affordable 20x60 mesh bone char that can be purchased online is Charcoal House in Crawford, Nebraska²⁷. They sell 6 pounds of bone char in a jar for $50 plus $20 for shipping and this is enough bone char to refill the filter 15 times and remove the fluoride in approximately 5,000 gallons of drinking water containing 700mcg per liter (e.g. 0.7ppm) of fluoride. Details on purchasing, assembling, and using the homemade bone char filter to make fluoride free Silicade and Fiji Water are at my blog²⁸.  

A Commercial Bone Chare Filter Made By Pure Earth Technologies: A fluoride water filter (model FL-BS) with a full canister (10” x 2/5”) of 100% fine mesh high calcium bone char that claims to remove 90% or more fluoride from tap water and last one year²⁹. Test data is provided from Maine Health and Environmental Testing Laboratory that shows a fluoride reduction from 11/18/2010 to 1/3/2012 of 2.1ppm to 0.2ppm³⁰. This filter sells for $41.95 online²⁹. Replacing this filter is 8 times more expensive than refilling a homemade bone char filter with fresh bone char (e.g. $5.14).

Pure Earth Technologies admit that a low flow rate is required for good filtration but don’t mention what flow rate or pH they used to prepare the test sample. In 2010 their tap was pH 8.59³⁰. The total volume of tap water passed through the filter is also not mentioned. This filter used with pH 8.59 drinking water for a family of two will likely not have sufficient capacity to remove 2 ppm of fluoride for a year. But when used with tap water adjusted to pH 3-4  it may have sufficient capacity depending upon the actual filter bed volume and the total volume of tap water filtered.

Recommended: RO and Distillation for Aluminum and Fluoride Removal

There are other methods of removing both aluminum and fluoride from drinking water and they include distillation and reverse osmosis (RO).  Their disadvantages are:

·         1. These methods like the Zero filter remove all essential trace elements in drinking water.

·         2. These methods require an initial investment in costly equipment and plumbing.

·         3. These methods require back flushing unlike the Brita, Zero, and bone char filters.

·         4. Chlorine should be removed as it damages the RO filter. 

Their advantages are:

 1.These methods pay dividends in not having to purchase replacement filters as often.

2. These methods may be required for fluoride removal if the total dissolved solids (TDS) are too high (greater than 300ppm) due to carbonate salts, as this makes acidification to pH 3 to 4 difficult due to pH buffering. 

RO filters have been tested and found to be more effective than distillation at lowering fluoride levels in drinking water³¹. It has been reported that RO filter systems, such as the Waterite³², remove fluoride down to 0.05ppm for the first 2 years of operation²⁶.  Chlorine in drinking water damages RO filters and must be filtered out with an upstream filter.  The chlorine filter requires more frequent replacement than does the RO filter and requires the user have some means of detecting when it needs to be replaced.

Non-recommended: Types of Commercial Bone Char Filters

Fountainhead Water Systems: An alternative to the homemade bone char filter system is a dual under-sink bone char fluoride water filter system made by Fountainhead Water Systems³³.  This system comes with two commercial bone char filters working in series, two faucet choices, a mounting bracket, and all parts and tubing required for installation. This is available from Amazon for $84.26.  The problems with this unit.

Fountainhead filters do not have much bone char as pointed out by a plumber who installed this unit for an Amazon reviewer.

Water flow is through the pleated side of Fountainhead filters and not restricted to bottom to top flow inside the filter resulting in low EBCT.

Bottom to top water flow through the entire filter bed would allow for greater EBCT and fluoride removal efficiency.  However the Fountainhead filters do not allow for complete bottom to top water flow. By replacing the Fountainhead filters with Pure Earth Technologies Model FL-BS filters bottom to top water flow would be allowed through the entire 10 inch filter bed. This modification would allow a Fountainhead system to work properly.

 Southern Cross Pottery: They claim their Fluoride Plus Filter with bone char will filter 2,000 liters of unspecified fluoride concentration or 12 months whichever comes first³⁴.  The filter’s speed is 1 liter per hour or approximately 1 gallon in 4 hours and it is claimed to remove 87% fluoride and 99% lead. This filter is made in the U.K. and will work in any unit that uses the Royal Doulton filter.  This filter sells for $89. Unfortunately there are no certifications or test results published by independent third parties on this filter. There are too many unknowns to recommend this filter. 

Recommended - Zero pitcher style filters

Zero pitcher style filters ZR-001 contain a mixed-bed of ion exchange beads that removes both cation and anions, including fluoride and the beneficial anion OSA¹⁹. Independent testing by the Water Quality Association (WQA) shows the Zero filter meets the NSF/ANSI Standard 53 for the removal of chromium, lead, and mercury³⁵.  Independent testing has also shown that this filter removes both 98.5% of aluminum, 93% of OSA, and 99.7% aresenic^19,36. Therefore 5-stage Zero pitcher style filters remove both essential trace elements and toxic ions from drinking water.

The anion exchange resin in a Zero water filter removes approximately 90% of fluoride^18,37.  Independent testing labs have found less than 0.1mg per liter (equivalent to less than 100mcg per liter) of fluoride in tap water that had been filtered by a Zero pitcher style filter^18,37. Zero claims their pitcher style filter is able to filter 25 to 40 gallons of water, assuming that the total dissolved solids (TDS) in the unfiltered drinking water is in the range of 51 to 200. However the Zero filter’s WQA rated service life is only 15 gallons making frequent filter changes required³⁵.

Ion exchange resins are expensive. For instance, Amberlite IRA-410 anion exchange resin that removes fluoride as effectively as bone char currently sells for $43 a pound while bone-char sells for $8.23 a pound, both in 6 pound quantities. This factor of five difference in price makes bone char fluoride filters preferred over fluoride filters using an anion exchange resin. The standard Zero pitcher style filter (e.g. ZR-001) is currently selling for approximately $16 each on Amazon. . Therefore the cost of Zero filtered water is approximately one dollar a gallon.

The WQA approved performance data is summarized in the following table³⁵:    

The Zero pitcher style filter is recommended but it is expensive and removes both toxic and essential trace elements from drinking water.

Non-recommended: Activated Alumina Filters

The most common commercially available selective fluoride removal is by filtration through alumina (i.e. aluminum oxide, or alumina ceramic).  Aluminum dissolves from the alumina in an amount dependent primarily upon both the pH of the water and the amount of fluoride in the water. Filtering pH 7 water is optimal with alumina because approximately 5.5 times more aluminum is dissolved from alumina at pH 5 versus pH 7 in the presence of fluoride³⁸. 

·         1. A pH 7 solution of 10,000mcg per liter (10ppm) of fluoride filtered with 800mg of alumina results in 35% of the fluoride being removed but 1,000mcg per liter of aluminum being added to the water³⁸.

 2. A pH 7 solution of 4,000mcg per liter (4ppm) of fluoride filtered with 200mg of alumina results in only 17.5% of the fluoride being removed but still 900mcg per liter of aluminum is added to the water³⁸.

 

·         3. Tap water of unreported pH containing 520mcg per liter (0.52ppm) of fluoride filtered with a new commercial alumina filter (e.g. Berkey), that was primed according to the manufacturer’s recommendation, resulted in 35% of the fluoride being removed but 5,090mcg per liter of aluminum being added to the filtered water³⁹.

 Therefore alumina only removes only a small percentage of fluoride while adding dangerously high levels of aluminum and for these reasons alumina can’t be recommended for fluoride removal.

Aluminum and Fluoride Should Not Be Added to Drinking Water

Both aluminum and fluoride are considered non-essential ions and pose health risks when present in drinking water. It is unfortunate for U.S. public health that aluminum addition to drinking water persists in the face of scientific evidence that it is a causal factor of two major epidemics: Alzheimer’s and autism.

Both aluminum and fluoride should not be added to drinking water.  Iron based coagulants have been shown to be just as effective and less expensive compared to aluminum coagulants for water treatment⁴⁰. Public water fluoridation was first practiced in the U.S. during the 1950s and as of 2012 approximately 435 million people worldwide (5.4% of the global population) were receiving fluoridated water with 214 million of them living in the U.S.².  The European Commission finds no benefit to water fluoridation compared with topical use for children².  Because fluoride in drinking water enhances aluminum accumulation by a factor of 2 and efficacy of supplemental fluoride for adults has not been established, it would be prudent to advocate topical use for children as done in Europe rather than community fluoridation^2,9.

Conclusion

Aluminum and fluoride are neurotoxic. Aluminum in drinking water has been linked to an increased risk of Alzheimer’s disease⁵. Aluminum has been found to accumulate in higher than normal levels in the brains of both familial and sporadic Alzheimer’s and in those with autism^6-8. Fluoride increases the accumulation of aluminum in the brain⁹.  Aluminum and fluoride ions react together to form aluminum tetrafluoride ions that impacts metabolism, growth, and differentiation¹⁴.

For just 24 cents a gallon 98.5% of aluminum and greater than 90% of fluoride can be removed from tap water. During the procedure sodium silicate (4 cents worth) can be added making a gallon of Silicade that contains 124ppm of aluminum and fluoride free OSA for healthy longevity¹⁷. This only requires a refillable homemade (DIY – do it yourself) bone char filter and a standard pitcher style Brita filter used in tandem to first remove fluoride and then remove aluminum while leaving the essential trace elements in tap water. This level of OSA has been proven to facilitate the elimination of accumulated aluminum from the body including the brain.

References
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2. Wikipedia – Water Fluoridation
3.  https://www.epa.gov/dwstandardsregulations/secondary-drinking-water-standards-guidance-nuisance-chemicals
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5. Crouse, D.N.; Prevent Alzheimer’s autism and stroke with 7 supplements, 7 lifestyle choices, and a dissolved mineral; Appendix VI. Epidemiology supporting aluminum’s causal role in Alzheimer’s disease; Etiological Publishing (2016)
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10.  Cottrell, von T.L.; The strengths of chemical bond; Butterworths Publication Ltd.; London; 2 (1958). Table 4.11 Bond dissociation energies
11. McBride, W.J., et al.; Radiofluorination using aluminum-fluoride (A118F); EJNMMI Res.; 3:36 1-12 (2013)
12. Martin, R.B.; Ternary hydroxide complexes in neutral solutions of Al3+ and F-; Biochem. Biophys. Res. Commun.; 155(3):1194-1200 (1998)
13. Li, L., and Fleming, N.; Aluminum fluoride phospholipase D activation by a GTP-binding protein-independent mechanism; FEBS Letters; 458:419-423 (1999)
14.  Wittinghofer, A.; Signaling mechanistics: Aluminum fluoride for molecule of the year; Current Biol.; 7:R682-R685 (1997)
15. Choi, A.L., et al.; Developmental fluoride neurotoxicity: A systematic review and meta-analysis; Environ. Health Perspectives; 120(10):1362-68 (2012)
16. Sun, M.M., et al.; Measurement of intelligence by drawing test among children in the endemic area of Al-F combined toxicosis (in Chinese): J. Guiyang Med. College; 16(3):204-6 (1991)
17. Crouse, D.N.; Silica water the secret of blue zone longevity in the aluminum age; Etiological Publishing (2018)
18. The People’s Chemist; Best fluoride filter: How to remove all fluoride (and chlorine) compounds from tap water;  https://thepeopleschemist.com/best-fluoride-filter-how-to-remove-all-fluoride-and-chlorine-compounds-from-tap-water/
19. Crouse, D.N.; Prevent Alzheimer’s autism and stroke with 7 supplements, 7 lifestyle choices, and a dissolved mineral; p149; Etiological Publishing (2016)
20. Crouse, D.N.; Unpublished research performed by the author (2016)
21. Whittier, J.; The value of tap water: A comparison of bottled, filtered, and tap water using the MWRA as a case study; Environ. Management I Harvard Extension School; Dec. 19 (2007)
22.  https://www.brita.com/wp-content/uploads/229915.001_BRT_RPL_Infinity-UserGuide-OB54.pdf
23. https://www.brita.com/wp-content/uploads/Longlast-PDS-with-401.pdf
24. Medellin-Castillo, N.A., et al.; Adsorption of fluoride from water solution on bone char; Ind. Eng. Chem. Res.; 46:9205-12 (2007)
25. Kanyora, A., wt al.; Fluoride removal capacity of regenerated bone char in treatment of drinking water; Asian J. Nat. Appl. Sci.; 4(1):30-6 (2015)
26. Make your own bone char filter; https://impressionsofaholobiont.com/2018/05/14/make-your-own-fluoride-filter-from-bones/  (2018)
27. https://www.charcoalhouse.com/store/water/20x60-mesh.html
28. https://prevent-alzheimers-autism-stroke.blogspot.com/
29. http://www.pure-earth.com/fluoride-water-filters.htm
30. http://www.pure-earth.com/PDF/bone-char-test.pdf
31. Prabhakar, A.R., et al.; The effect of water purification systems on fluoride content of drinking water; J. Indian Soc. Pedod. Prev. Dent.; 26(1):6-11 (2008)
32. https://www.waterite.com/
33. https://www.amazon.com/UNDERSINK-CARBONS-FLUORIDE-FILTER-SYSTEM/dp/B01HOC9872
34. http://www.southerncrosspottery.com.au/replacement-filters-taps/scp-fluoride-plus-new.html
35. https://www.zerowater.com/docs/Performance%20Data%20Sheet%20for%20all%20certified%20devices%206-1-15.pdf
36. Barnaby, R., et al.; Effectiveness of table top water pitchers to remove arsenic from drinking water; Environ. Res.; Oct.; 158:610-15 (2017)
37. Carr laboratories results: https://www.youtube.com/watch?v=4V8BqiHpmzk
38. George, S., et al.; Residual aluminum in water defluoridated using activated alumina adsorption – modeling and simulation studies; Water Res.; 44:3055-64 (2010)
39. https://www.healthyfamiliesforgod.com/blog/2018/1/25/is-your-berkey-really-filtering-your-water
40. Yonge, D.T.; A comparison of aluminum and iron-based coagulants for treatment of surface water in Sarasota County, Florida; Thesis submitted to: Dept. of Civil, Environmental, and Construction Engineering; University of Central Florida, Orlando (2012) 

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