Drinking water filters - when to change element?

[The Natural Philosopher]

And next time you write breach, make iot look more like a gap, and less like an arse.

[mike ring]

[e-mail] wrote in news:bpffq8$1njh8q$ [e-mail]- berlin.de:

A "sighted" test in my glass teapot says filterd water produces a much paler brew, which strangely gives the same shade of brown in the cup.

There is also no sludge at the bottom.

As the filter ages the tea goes dark and muddy.

I *only* use it for tea; I think otherwise the impurities are good gor me, at leest vey've mevver bun be eddy har

[Huge]

[22 lines snipped]

Actually, it is of no consequence in adults.

[Huge]

No it isn't. At least not in the doses involved in water fluoridation.

I trust you don't eat iodised salt?

[The Natural Philosopher]

Or polar bear liver. Overdose of vitamin D or something. Deadly. Of course without vitamin D you die as well.

Nature has seen fit to provide us with lots of natural hazards. As well as naturally fluoridated water. Observations that teeth decay was less in these areas, and that no one died perceptibly younger, or suffered ill effects like trying to take over the world (Austrian Invincible Dictator Syndrome) was what led to the decision to put teeny amounts in drinking water.

Who was it calculated that potatoes would not pass current FDA screening? Too much arsenic or summat.

[Andrew]

Do a real comparison by standing the unfiltered water in a jug too. If chlorine is the problem then this is supposed to make a difference.

[Adrian Sims]

Nonsense. Fluorine compounds are cumulative poisons and build up in the teeth and bones over the years weakening both. That is totally different to the poisoning effects of oxygen.

If you research the so-called benefits you will find they are very much disputed. Fluoridation, where it is done, is done out of ignorance or for political reasons.

The site may be crap in terms of it's organisation - but it references many other sources - google will turn up plenty of information about the harmful effects of fluoride and you can find details of studies which show zero benefit from fluoridation of water supplies.

[Grunff]

Like most paranoid conspiracy theorists, you are mixing up two totally different questions:

[a] Does fluoridation have any benefits? [b] Is the presence of low concentrations of fluoride in drinking water harmful.

As far as [a] is concerned, it appears the answer is 'probably yes, at least for young people'.

As for [b], there is no credible evidence which suggests that this is true.

[Dave Plowman]

Why would a government spend money on something like this out of ignorance or political reasons? Does it change Socialists into Blairites or something?

[Rob]

Martin is correct. Activated carbon holds onto some compounds well and others weakly. When it gets heavily loaded the strongly held compounds start pushing the weakly attracted compounds off. Fortunately most toxic compounds are strongly attracted but there are possible exceptions which is why manufacturers cover their backs by recommending frequent renewal.

[RichardS]

Chilling water in a bottle in the fridge is a surprisingly effective method for removing unpleasant tastes as well.

I no longer bother with filters and the like. I drink bottled water, but that's mostly carbonated stuff and it does have a pleasant flavour of it's own.

cheers Richard

-- Richard Sampson

email me at richard at olifant d-ot co do-t uk

[Adrian Sims]

Nonsense. I did not mix these up in any way. I addressed both these points separately.

Both statements false.

For [b], low concentration is irrelevant as F is a cumulative poison. There is much evidence that it is a carcinogen. It also promotes osteoporosis.

A.

[Grunff]

How the hell is it cumulative? That is just plain wrong. Cite one paper which states that fluoride ions are cumulative, then we can continue this conversation. Otherwise there's really little point.

[Richard]

A water filter of the type you describe has several factors which determine its optimum life. The quality of the water going into it, the amount of water going through and the length of time. No manufacturer can accurately determine the first two without testing your water and putting a meter on the filter. If as you say your use is minimal, then it is likely that the 6 months described in the manual is more of an arse covering recommendation. That said the 3rd measure, time, should not be ignored. I would suggest you are unlikely to taste increased bacteria, and that a taste test or a flow test is thus not sufficient. I have a very large Britta water filter on my coffee machine in my cafe, and the local environmental health insist that regardless of usage, it must be changed at least annually. Personnaly I would likewise change a home filter annualy. It is better to be safe than sorry.

Richard

[Adrian Sims]

The fact that there are conditions known as dental fluorosis and skeletal fluorosis should suggest that fluorine compounds do accumulate in the body.

Although the following paper is found on an anti-fluoridation website, it was first published in the journal of the International Society for Fluoride Research. I don't claim the research or the paper to be brilliant...it was simply the first thing I could find. It makes interesting reading however.

You could also read this article about fluoride buildup in bones. It's written by a journalist but quotes a Canadian doctor (who is pro-fluoride in toothpaste) as saying "What we're finding indicates a trend: Torontonians have double the fluoride levels in their hip bones compared to Montreal, where water is not fluoridated."

Adrian

[RichardS]

You can just never tell with governments. Depends on who has who's ear at an opportune moment.

Look at the current Part P proposals as a good example.

Personally, I'm not particularly worried about the toxicity of flouridation - as others have pointed out there are natural occurences of flouridated water and no statistical evidence about adverse effects.

This isn't similar to chlorination of the water supply - that is a treatment to prevent water-distributed diseases. This is mass medication via the water supply, and that is a very slippery slope to go down.

-- Richard Sampson

email me at richard at olifant d-ot co do-t uk

[Huge]

[17 lines snipped]

Only by loons. Do you have any non-loon sources? The website you posted earlier is a loon one.

[Huge]

Citations, please. Peer-reviewed journals, or equivalent. Not loon websites.

[David Micklem]

In article , Grunff wrote:

Grunff, I really think you are out of date on this. "Everbody" knows that fluoride is good for your teeth and an all round good thing. Politicians like to tap into this widespread feel-good factor. Unfortunately, as with many other things, what everybody "knows" often turns out to be uncertain. I'm not saying that fluoride is _definitely_ ineffective or damaging but the scientific jury is still out. In any case, why waste money adding it to water, especially as only about 1% will be drunk, the rest getting dumped in the environment? In the form of toothpaste it is carefully targetted to the teeth, and comes with the added advantages of regular brushing!

Specifically for a ref for a cumulative effect of F-, reference 1 below (including abstract, with emphasis of relevent text) is a review, but its in a respected journal.

In any case, although acute toxicity _should_ be of little concern, at least seven incidents of acute fluoride poisoning related to fluoridation of the water supply were officially reported in the USA between 1974 and 1992, resulting in 655 cases and 2 deaths so it is not totally without risk. The minimum toxic doses were estimated to be as low as 0.2-0.8 mg per kg of body weight in children which is not fantastically far off the 1mg/day target intake via fluoridated water. The incidents were caused by accidents, such as pump faults, which can be expected to recur (Ref 2 below).

Young and unborn children are a particularly vulnerable group to whom any benefit of fluoride may be outweighed by harmful effects, for example on brain development (Ref 3), and for whom minimum toxic doses are likely to be even lower. We simply don't know.

Refs 4-7 address the damage (physical and psychological) done by dental and bone fluorosis.

I agree that the originally posted site is pretty gruesome, but you might want to use

as a starting point. Better still, read the University of York's highly respected review of fluoridation at . The 'executive summary' is that there simply haven't _been_ any good-quality studies of the effects of fluoridation. i.e. Scientifically, we _do not know_. To quote them:

Sorry for such a long post,

David

Refs:

1: Crit Rev Oral Biol Med. 2002;13(2):155-70.

Dental fluorosis: chemistry and biology.

Aoba T, Fejerskov O.

The Nippon Dental University, Department of Pathology, 1-9-20 Fujimi, Chiyoda-ku, Tokyo 102, Japan. [e-mail]

This review aims at discussing the pathogenesis of enamel fluorosis in relation to a putative linkage among ameloblastic activities, secreted enamel matrix proteins and multiple proteases, growing enamel crystals, and fluid composition, including calcium and fluoride ions. Fluoride is the most important caries-preventive agent in dentistry. In the last two decades, increasing fluoride exposure in various forms and vehicles is most likely the explanation for an increase in the prevalence of mild-to-moderate forms of dental fluorosis in many communities, not the least in those in which controlled water fluoridation has been established.

**START MY EMPHASIS** The effects of fluoride on enamel formation causing dental fluorosis in man are cumulative, rather than requiring a specific threshold dose, depending on the total fluoride intake from all sources and the duration of fluoride exposure. ***END MY EMPHASIS

Enamel mineralization is highly sensitive to free fluoride ions, which uniquely promote the hydrolysis of acidic precursors such as octacalcium phosphate and precipitation of fluoridated apatite crystals. Once fluoride is incorporated into enamel crystals, the ion likely affects the subsequent mineralization process by reducing the solubility of the mineral and thereby modulating the ionic composition in the fluid surrounding the mineral. In the light of evidence obtained in human and animal studies, it is now most likely that enamel hypomineralization in fluorotic teeth is due predominantly to the aberrant effects of excess fluoride on the rates at which matrix proteins break down and/or the rates at which the by-products from this degradation are withdrawn from the maturing enamel. Any interference with enamel matrix removal could yield retarding effects on the accompanying crystal growth through the maturation stages, resulting in different magnitudes of enamel porosity at the time of tooth eruption. Currently, there is no direct proof that fluoride at micromolar levels affects proliferation and differentiation of enamel organ cells. Fluoride does not seem to affect the production and secretion of enamel matrix proteins and proteases within the dose range causing dental fluorosis in man. Most likely, the fluoride uptake interferes, indirectly, with the protease activities by decreasing free Ca(2+) concentration in the mineralizing milieu. The Ca(2+)-mediated regulation of protease activities is consistent with the in situ observations that (a) enzymatic cleavages of the amelogenins take place only at slow rates through the secretory phase with the limited calcium transport and that, (b) under normal amelogenesis, the amelogenin degradation appears to be accelerated during the transitional and early maturation stages with the increased calcium transport. Since the predominant cariostatic effect of fluoride is not due to its uptake by the enamel during tooth development, it is possible to obtain extensive caries reduction without a concomitant risk of dental fluorosis. Further efforts and research are needed to settle the currently uncertain issues, e.g., the incidence, prevalence, and causes of dental or skeletal fluorosis in relation to all sources of fluoride and the appropriate dose levels and timing of fluoride exposure for prevention and control of dental fluorosis and caries.

1. Akiniwa, K. Fluoride 30(2) 89-104, 1997
2. Lu, Y. et al. Fluoride 33(2) 74-78, 2000
3. Tabari ED et al Brit Dental J 189, 216-20, 2000
4. McDonagh MS et al Brit Med J 321, 855-9, 2000
5. Collins MA & Zebrowitz LA J Appl Social Psychol 25, 129-163, 1995
6. Lee, JR Fluoride 26(4) 274-277, 1993

[The Natural Philosopher]

Yup. Its all the magnesium, sodium and calcium ions in it, and provabaly fluoride as well.

:)