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Do carbon block water filters actually remove some fluoride?

by artellan
Tags: fluoride
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artellan
#1
Jul22-11, 12:03 AM
P: 5
Hi! This is my first post on physicsforums. I wasn't sure if it belonged here or in the Chemistry forum, but just picked here.

I am trying to figure out if my drinking water filter system removes some fluoride from my water. (I know it doesn't remove all as it's not specifically a fluoride filtering system.) It's a dual filter carbon block undersink system, made by GE (FQSVF is the filter). Although the manufacturer claims that it does not remove fluoride, I have read that activated carbon filters may actually reduce 40-60% of fluoride in water, especially when fluoride is being added to the water supply in the form of man-made forms of fluoride such as hexafluorosilicic acid.

Here is a quote from Aquasana.com who make a similar activated carbon system:
"Aquasana systems do remove 2 of the 4 fluorine isotopes, giving you a 40-60% overall reduction. The portion of the fluoride our system filters out is the synthetic portion, while leaving in the naturally occurring fluoride. However, you will not find this on our performance data sheet because of the percent of reduction. Our testing documents only list those contaminants that have been certified to be removed at a rate of 97% or greater, so we cannot include fluoride on the list. "

Does that quote even make sense from you know of water filters? If so, is it reasonable to suspect that my GE system would operate similarly with respect to fluoride?

Note my filter specs can be found at:
http://products.geappliances.com/ApplPro…

Thanks in advance.
Mike
Winnipeg, Canada
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meplumber
#2
Jul23-11, 09:02 AM
P: 23
I am not an engineer, just a plumber. Water treatment has become higly gov't regulated in both the US and Canada. Most manufacturers only publicize the contaminants that they can remove above the federal mandates. Which for most contaminants is the 97% that you mentioned.

I cannot speak to the chemical processes at play inside of the Activated Charcoal/Carbon filters. I feel that I am only qualified to say that removal of synthetic additives is very common with water treatment systems of all types.

Sorry that I could not be more helpful.

Good Luck.
artellan
#3
Jul23-11, 08:56 PM
P: 5
Thanks very much for the reply. I've actually submitted the question to GE customer service, and already got a response saying they would research it for me. So hopefully I will get some kind of answer ...

At the very least I can probably make them explain the statement on the box that it "does not remove fluoride", i.e. does that mean it's guaranteed to not remove ANY fluoride, or just that it doesn't remove more than 97% of fluoride (or maybe, only remove synthetic fluoride).

It's kind of funny, you'd think their marketing department would realize that for most people who buy filtration systems, removal of fluoride is a PLUS!

Cheers
Mike

artellan
#4
Jul23-11, 09:07 PM
P: 5
Do carbon block water filters actually remove some fluoride?

Just noticed a reply from GE in my inbox. I must say I'm impressed with their responsiveness so far (email on a Saturday morning!) ... hopefully their "SmartWater team" that is doing further research will be able to give a useful answer.

Here is the email:
Good Morning!

Thank you for your help too! ... I should be getting a response from our research team here within the next 24 hours.

I have forwarded your e-mail to our SmartWater team for review and handling also. They will contact you as soon as possible to provide further assistance and answer any additional questions you may have.

Thank you again for contacting GE and I apologize for any inconvenience this situation has caused you. I appreciate your patience and please don't hesitate to contact us in the future should you need further assistance. Have a nice day.

Cordially,
...

Appliance Specialist
Consumer e-Response Team
GE Appliances
artellan
#5
Aug3-11, 11:22 AM
P: 5
Well, in the end GE did not provide any answers, they just said "we have not made any public statements about fluoride removal".

I actually thought the filter box said "does not remove fluoride" but I checked again and it doesn't say that (it doesn't mention anything about fluoride anywhere). It's actually on various third-party sellers' websites (e.g. filtersfast.com) that it says "FQSVF does not remove fluoride" but maybe that's not official GE statement.

So, the filter may or may not remove some fluoride; GE is not providing any information on that.

Someone on yahoo answers said that the Aquasana statement about fluorine isotopes doesn't make any sense, and therefore they can't be trusted. I'm inclined to think that might be the case. But it might also be the case that they did test and found their filter removes 40-60% of fluoride, and it was a non-scientific marketing person who wrote the explanation on their website.

So final conclusion is, my carbon block filter may or may not be removing some fluoride, and there's no way to find out unless I actually get my water tested!
cyclonis
#6
Feb23-13, 06:22 PM
P: 2
Artelan if you are still around ...i found some interesting information while browsing and viewing your post on this forum...

http://www.cda-adc.ca/jcda/vol-74/issue-5/443.html


Results: Hollow-fibre membrane filters did not affect fluoride concentrations in the fluoridated water, but activated-carbon filters removed some fluoride, especially from the pure-water solution. Filtering a pure-water solution with a fluoride concentration of 0.8 mg F/L reduced the fluoride concentration until 210 L of the solution had been filtered. However, filtering a tap-water solution of 0.8 mg F/L reduced the fluoride concentration only until 8 L had been filtered. The concentration of absorbed fluoride in the filter at 10 L of filtration was 4.7 mg/kg activated carbon.

ironically enough from the Journal of the Canadian Dental Association

but they inadvertently said there are some truths to the carbon filtration. Thats why they are not allowed to talk about it because the corp government would **** their pants if people stacked up multiple carbon filers persay down the same line ;)
artellan
#7
Feb24-13, 09:35 PM
P: 5
Wow, thanks for the information cyclonis. Very interesting. So it appears that immediately after changing my filter it may be removing a fair bit of fluoride, but that such filtration ability falls off quickly the more water is filtered.

Of course, it's hard to say how much that study applies to my situation (their tests were using sodium fluoride, whereas Winnipeg is using Hydrofluosilicic Acid).

I have been considering an fluoride filter which can be added inline to my existing filter: http://www.pure-earth.com/fluoride-water-filters.htm

And of course, hoping to get a bunch of people to sign the 'fluoride free winnipeg' petition.

Thanks again!
cyclonis
#8
Feb24-13, 11:15 PM
P: 2
No Prob....ironically enough im trying to get my municipality to end fluoride...we have a fluoride free toronto site already ;) .... i sent a letter to york region.


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