Assamica Agro Green Adventure and Tulsi Green Sensation

Assamica Agro Green Adventure

Tulsi Green Sensation

I'm trying out two more teas from Assamica Agro, a tea producing cooperative from Assam.  This time I'm onto a plain green tea and a blend (their Green Adventure and Tulsi Green Sensation).  Tulsi wasn't familiar, but from their description it rings a bell:


Being known as the queen of Indian herbs, it was only natural to include tulsi in our tea blends. Tulsi or Holy Basil is one of the most precious herbs in traditional healing methods. This spicy and warm sensation will help you relax and charge your batteries for a new day, while offering a very pleasant flavor combining anis, basil, cardamom and mint notes all in one. Fresh and deep green tea is serving as a base of this perfectly balanced blend. Mild and pleasant scent of brew is matched by a delicate and savory flavor.  


Holy basil is familiar; we cook with that here.  This reference goes on and on about health benefits.  And I thought it was just another type of basil.

Review

The green tea smells fruity and rich, with a bit of concord grape to the scent, and earthy and mineral notes below that.  It actually smells nice, for a green tea, which is not exactly my favorite category.  That grape scent is not all that closely related to muscatel, another somewhat grape-like range of Darjeelings (or in some Oriental Beauty  Taiwanese oolongs), with that version closer to citrus.

The Green Sensation reminds me a lot of Vietnamese green teas as I first try it.  Those have a distinctive mineral base of flavors that is common to this, with differences in the other flavors.  There is some vegetable, as with those teas, as in those close of kale (which works better than it sounds, but if someone really hates kale then maybe not for them).  Beyond that secondary aspects are more floral than fruity.  Given all that is going on it comes across as complex.  The mineral helps it work, and the sweetness is nice, with clean and bright flavors.  If the taste ranged into cooked kale more--or cooked spinach, or other cooked vegetable range--it wouldn't be as pleasant, but it doesn't, it stays fresh and bright.


Since I wrote these notes I retried a version of Vietnamese tea I wanted to mention, which is pretty close to this one in character.  It's somewhere between kind of crazy and slightly bad form to put a tea review inside a tea review (like a Russian doll, someone once mentioned) but check out this green tea description for Hatvala's Vietnamese Purple Rain:


...distinctive taste which is a little earthy but with flavours that hint of mushrooms and other vegetables such as artichoke and asparagus.  Brewed sympathetically it will show off its natural sweetness with no bitterness.

Hatvala Purple Rain green tea (Vietnamese instead, but still a bit similar)

that tea that day; not the way they drink it

The "brewed sympathetically" in that tea description seemed to mean using cooler than boiling point water (around 75C / 170F, but that varies per preference), and not over-steeping it; nothing too demanding, how anyone would brew green tea.  Except most Vietnamese people, it seems; they tend to like the astringency and go with full boiling point water without limiting infusion times (per my limited understanding).



The last time I was in Hanoi (almost three years ago now; the time just flies) cafe staff brought a pot of green tea to drink, and trying the first cup I noticed it was a little edgy, from that boiling point water temperature choice.  I started to panic when five minutes went by and the pot still had the leaves brewing in it.  There was no way to "drink down" a pot of boiling hot tea, tiny cup after cup.  It must have seemed silly to them for a customer to dump the whole thing out in water glasses to stop the infusion process at that stage, but I did already get enough of the effect of where the extended infusion time was heading.  Hanoi is awesome to visit, by the way, a generally cool spot.


This is probably a good place to go back and cite the Assamica Agro Green Adventure description:


Smooth and tingling, moss and mushrooms with mineral notes that change to leafy vegetable flavor with subsequent steeping, light astringency that melts into a sweet aftertaste.


I noticed they had more interesting product information on that page:

picking tea in Assam (credit Assamica Agro Facebook page)

PERFECT FOR:  Deep and autumnal taste, perfect for refreshment in chilly days. 

SEASON:  Second Flush, 2017 

FARMER:  Prithivi Group of Small Growers, Dibrugarh (Assam)

CERTIFICATION:  This tea is produced following India's National Program for Organic Production (NPOP) Standards.  



I'm not so sure about the fall day theme but it is interesting that the teas are harvested in flushes (like Darjeeling), that the producer is a co-operative of sorts (I probably should have said more about that by now in earlier reviews), and that the teas are organic.


Neither of the descriptions for the Vietnamese tea or the Assam mentioned kale but they both taste a bit like that to me.  I'm not noticing mushroom so much in either, but some flavor depth for both could be that.  Unless I'm remembering wrong both have some floral tone to them, and a good bit of mineral base, and are kind of similar.  Good Vietnamese green tea is a nice thing, and even ordinary versions are nice, very consistent, with that "Purple Rain" version a good bit better and more interesting than average.  It's a good tea to seem similar to, for the Assam version, if someone is into complex, clean-flavored, mineral based, slightly vegetal green tea with some rich floral tone.


I'm not necessarily noticing the concord grape (in the Assam tea; back on target here).  There is a lot going on for flavors though, and it could include that.  I'd also list citrus, and the floral range is along the lines of lavender, on the rich side.  To the extent that I like green teas in the normal range for green teas I like this one.  It's not really astringent, the balance works, and it's not "straight grass."

Tulsi left (a bit darker than plain green tea), Green Adventure right

The Tulsi Green is really an herb blend, something I don't get to much.  I drank tisanes instead of tea for a long time, for something like 15 years, so I'm open to the experience of them, and still dabble in them a little.  I just never get around to drinking tea and herb blends, since I tend to value the simple, natural range of aspects in plain teas.  I really appreciate the way complexity and subtlety can result from using only one type of plant leaf processed in one way.

The scent of this dry tea is a bit like incense, or a spice blend, kind of hard to describe, but appealing, and bit intense.

I guess it tastes like infused tulsi (holy basil; one kind of it since there are two).  It's closest to lemongrass, based on spices range I'm familiar with, but comes across as an herb blend that also includes lemongrass, with that as only a base for part of the flavor range.  It shares some taste range with licorice.  Of course I mean the black candy and plant type, although I only ever tend to experience the plant flavor in better versions of the black candy.  It's funny how the Twizzlers version sort of tastes like that and sort of doesn't.  That candy is still nice, it just doesn't taste exactly like real licorice.

The complex flavor range doesn't leave off there, but that's where a struggle to describe it picks up.  A lemongrass and licorice blend would taste like this, but it goes further.  That probably would be a good idea for an herb blend, based on trying this.  That reminds me to check what licorice really is, since I'm only familiar with the somewhat chewy candy:


Liquorice (British English) or licorice (American English) /ˈlɪkrɪʃ, ˈlɪkər-, -ɪs/ LIK-(ə-)rish, LIK-(ə-)ris)[5] is the root of Glycyrrhiza glabra from which a sweet flavour can be extracted. The liquorice plant is a herbaceous perennial legume native to southern Europe and parts of Asia, such as India. It is not botanically related to anise, star anise, or fennel, which are sources of similar flavouring compounds.

Most liquorice is used as a flavouring agent for tobacco, particularly US blend cigarettes, to which liquorice lends a natural sweetness and a distinctive flavour and makes it easier to inhale the smoke by creating bronchodilators, which open up the lungs.[6][7] Liquorice flavours are also used as candies or sweeteners, particularly in some European and Middle Eastern countries.


Cool, I did not know all that.  Funny how the British are about spelling.

It might have a sweet tone to it that could be floral, it's just hard to isolate as that.  A hint of spice is out towards one that I'm not completely familiar with, maybe tumeric or coriander.  I do cook and eat lots of foreign foods but my range of taste awareness still has limits.  I can barely remember the names for different types of flat breads with Indian foods.

It's odd this doesn't taste that much like basil, any kind of it.  This herb version I cook with isn't just like sweet basil, and definitely not like Thai basil, which tastes a lot like mint, but in cooking it did seem to remind me more of sweet basil than this tea does.  Then again I'm always mixing it with food, and drying an herb can change the flavor more than one might expect sometimes.  Or it doesn't always seem to, it depends on the herb.  Dried rosemary infused as a tisane tastes a lot like fresh rosemary and infused papaya leaf varies lots in taste depending on if you heated it at all during drying or not.

Second infusion

I'm brewing these Western style so there won't be a long list of different infusions to comment on; this second will do, even though these will surely brew a third.

The green tea didn't transition that much, at least in one sense.  The flavor might be a little less bright, filling in some depth in richness instead, with the mineral range broadening.  It's funny how shifting the balance of aspects really did change this tea but I would still describe it using the same concepts, it's just not the same with them layered differently.  With that mineral picking up as much as it did it's now on the flintier, limestone side leaning a little towards metal.  That might sound horrible but I don't mind it; it's the grassy, seaweed or cooked vegetable range I don't care for in green teas.

The kale had been ok, but the overall balance has shifted more towards mineral now, with some floral undertone hanging in there.  But that's a personal preference thing: someone else could love or hate seaweed or intense mineral.  And likes can change over time.  I started out on Japanese green teas, and did like that seaweed / grass range in those, and then later moved on to liking black teas and more roasted oolong aspects range most.

The "Tulsi" tea is fading just a little, but still plenty intense.  It lost a little in terms of the brightest range, and picked up depth and earthiness.  The lemongrass related effect dropped off a little, and the licorice picked up.  I guess it must taste a lot like holy basil, but then I can pick that up locally, dry it out, and check further to verify that.  It has an interesting mouthfeel too, a slight drying effect, which I don't find to be positive or negative, just different.

I have to close this on the early side.  It's time to chase the kids, who seem to be trying to tear down one of the walls from the sound of it.  I did brew a couple more infusions later but didn't take notes on those; as likely it was more of the same, with limited transition.

Both teas were nice, and trying out a tea and herb blend went better than I would have expected.  They included a rose petal and green tea blend sample, way off what I usually drink, but if that turns out to be interesting I'll mention it.  They also sell the rose petals as a plain tisane and I think per my preference I might like that better with black tea, and it would be easy enough to buy both from them and mix them.

they look like trouble, don't they?

Yi Qing Yuan factory Hunan Fu brick tea with golden flowers

Fu brick; yellow spores vary in different layers

More of reviewing hei cha from a Yunnan Sourcing purchase, a Fu brick tea as described in the title.  This is the fourth and last review along those lines, with one black tea in that order still to go.  The last related post reviewed a hei cha brick from Hunan that didn't have golden flower spores introduced to the tea, and although it won't be possible to separate out that one input from other differences it will be interesting comparing both.

I really just keep including that order summary graphic to look up what the teas are, but in this case there isn't much detail there.  I'll also add the Yunnan Sourcing description:


This is a 10 gram sample portion of larger Fu brick tea fermented in 2009. Made by the Yi Qing Yuan tea factory in An Hua county of Hunan province. Special traditional fermentation process gives the tea a mellow, sweet and spicy taste.  Golden Yellow spores called "golden flowers" (金花) have been allowed to flourish just after pressing, which gives this Fu Brick a unique taste and feeling.


I wanted to add just a little about what the "golden flowers" are, and although I didn't find the type of description I had in mind I had recently read a "Mattcha's Blog" post covering that (one that also included links related to fluoride levels in some versions of hei cha, another subject I've been on recently):


What gives fu zhuan cha its regulating, harmonizing, centering, and grounding properties is its special production method. Its production is rather complex and involve twelve steps which include: fresh picking of leaves, panning, pile fermentation, rolling, drying, softening with steam, piling, partitioning, pressing into bricks, fungal fermentation, drying, packing and storing. In the end there are many pro-bacterial flora that proliferate in the finished tea the most commonly recognized is the eurotium cristatum bacteria which produces fu zhuan's famous "golden flower" yellow mold. It is famous because it is most noticeable to the naked eye. However many other bacteria are found in fu brick tea, and not all brick tea contain golden flowers.


Zhuan means "brick," more or less (but it sounds better than brick); and the rest I could live with as explanation, but I did look further into one reference on this bacteria versus fungus issue:


Microbial counting and identification revealed that genera Aspergillus, Penicillium, and Eurotium were the dominating fungus during the manufacturing process of Fu brick tea6, 7...  

A recent studies using PCR-DGGE analysis revealed that the microorganisms found in Fu brick tea were from or closely related to the genera Aspergillus, Beauveria, Debaryomyces, Eurotium, Pestalotiopsis, Pichia, Rhizomucor, and Verticillium10, while other studies found that Aspergillus niger, Blastobotrys adeninivorans and Bacillus, Enterobacteriaceae were the major fungal and bacterial communities involved in Pu-erh tea, another kind of post-fermentation tea11, 12. 


It might sound like that's the summary then, but that was only the introduction to their own review, with a bit more about that one input following:


Since the recent synonymization of the teleomorph-based genus Eurotium with Aspergillus by the International Commission on Aspergillus (ICPA, 2012), which adopted the newly established principle “one fungus, one name” (Norvell, 2011), species formerly included in the genus Eurotium are displayed with their Aspergillus name27. Many previous reports showed that Aspergillus cristatum (Eurotium cristatum) was the dominant fungus during the manufacturing process of Fu brick tea31, 32, and it is considered to be safe under low- and high-osmolarity conditions...


So it's a fungus.  It's all so clear already, but if that's of interest do give the rest of the paper a close read, since there's lots more to it.  On to seeing if I get harmonized and centered.

Review:

in gaiwan; lighting changes the tea color in photos

The scent of the tea isn't very intense; it's vaguely earthy, a little sweet, and as much as scent comes across it seems complex.  The brewed tea will tell more of the story.


I let the initial infusion go a little longer, to a standard time, and didn't use a rinse.  For drinking this tea regularly it would probably be a good idea to (not to be alarmist but a limited amount of toxins is an output from some types of tea fermentation), but I wanted to see what that part tasted like in this try.


It's nice; still subtle in this infusion, and will probably get going a bit more in the next.  It is earthy, a bit subdued, and pleasant, definitely not off in any way, not musty, or nasty.  One flavor aspect is definitely unusual and unfamiliar but it doesn't strike me as off.  I'm assuming that's the input of the golden flowers but more tasting and reading background on what that is supposed to contribute could help pin that down.


I'll take a quick stab at what I'm experiencing now and move onto more conclusive definition in the next infusion.  Do you know that sweet, minerally, slightly earthy scent that a steel pipe gets after it's been outside in the open weather for a very long time?  It doesn't smell anything like rust at that point, although it is more or less a form of rust.  It's a little like that.

old oil tank and pipes (credit here, with background on oil history)

Permit me a bit of related tangent:  I grew up near enough to Titusville, PA, the home of the first commercial oil well, an experiment by Colonel Edwin Drake in 1859.  I actually lived closer to Oil City, the center for oil refining for roughly a century after that, a history that only ended when the last of the refineries moved out within the last 20 years or so.  Oil well equipment was everywhere, and some still is, with some history and modern issues covered in this article.  I suppose that old equipment having a nice smell wasn't the most significant aspect, for most, but to me it was the smell of history itself, even of my personal history.  One of my grandfathers worked his whole life maintaining oil well equipment, and my family would go hunting in an old oil production area.  There were earlier levels to the local history than that, with old smelting furnaces from an earlier part of the industrial revolution still buried in overgrown woods, and Indian relics around from before that, with stone ruins and stories supposedly from an earlier people before them.  But this is all plenty for one tangent.

more "flowers" in different layers

I went about the same time on the next infusion, on the order of half a minute, expecting this tea to still be opening up.  I think I'll probably go a little longer next time to experience a more intense version of it, but there should be plenty to taste at this strength.


The flavor is nice, if anything a little sweeter this time.  In one sense it has good complexity; there is a good bit going on with the rich, clean flavors.  In a different sense it's quite simple and straightforward; the feel isn't thin, but it doesn't have lots of effect on different parts of your mouth.  It's simple in the sense of all the flavor range being kind of related, as a full set of aspects but within a limited range.  It's nice, to me, but it does possess an unusual set of earthy flavors, and people drinking teas for mouthfeel-based effects might see that side as more of a gap.


In a sense I'm not really completely sold on describing teas as tasting like ten other aspects, related to that not being fully descriptive.  I never really reject those sorts of analysis, even though they tend to vary by individual, so that even two people I would be inclined to trust tend to pass on different lists for the same tea.  It seems like a valid but limited approach, although to some extent any description of something that is completely experiential would be limited.  Can you really describe experiencing a sunrise, or roller coaster, or the difference between good french toast and an average version?  You can definitely use concepts to remind someone of their own related experiences, or even to explain how yours varied slightly, but at some other level the words fail to model the impression.


A flavors list it is then.  Sweetness reminds me of malted barley, not really "malt" in one the same senses I keep using it, but it has a grain-like background to it.  "Above" that the one unusual flavor aspect sits, in the same type of range, one that is hard to pin down.  It doesn't share the rust-like components of old rusty pipe, just the other mineral and earthy sweetness.  Mineral is doing something unusual in this; it's soft, not at all pronounced, but there is a layer that relates to that.  It's nothing like the mineral in Wuyi Yancha, or Taiwanese high mountain oolong, but of the two it reminds me more of the underlying tone that comes with sweet, mineral-like lightly oxidized oolongs from Taiwan.  The mineral undertone might be lighter than in that last Hunan hei cha.  It's not as earthy as one might expect; nothing at all like a range typically found in shou pu'er (although the one in this set wasn't exactly typical; it was light, smooth, and sweet).  I'll go with a longer infusion next time and see if I can't split the list out further.

An even stronger infusion does help with intensifying the experience.  I get the impression this tea would still be fine doing a two minute soak at Gongfu proportion, it might just be a bit stronger than ideal.  That sweetness reminds me a little of the sweet smell of fresh cardboard boxes in this.  Usually when I'm saying a tea tastes like cardboard I mean that negatively, but not this time.  It would seem odd to drink this tea very regularly, to go through a kilo of it, but I really would appreciate drinking a few hundred grams regularly until the novelty wore a little thin, and keeping it in a periodic rotation after that.


The subtle fruitiness present in it might be along the lines of longan.  To be clear I mean longan and not longkong (as that second similar fruit is called here); it tastes a little towards brandy versus the other similar fruit range leaning towards grapefruit.  A Huffington post article compared rambutan, lychee, and longan but stopped at saying longan has a "more tart and distinctive flavor."  It's like that, except that tart is completely wrong; they're not tart at all.  That writer botched the other two fruit descriptions too, saying a rambutan is richer and creamier than a lychee, and a lychee balances being sweet and tart.  That all works for average lychee but the levels of both tartness and sweetness vary a lot.  When you get a good version, from the right plant-type that is perfectly ripe, they're so sweet and complex that the rest of your world basically shuts down while you experience it, and for some plant types you'd have to say they taste a little like spice, maybe towards nutmeg, just not exactly that.  There were longan on the dining room table yesterday but today it's rambutan, and lychee season here seemed to be a month ago.  Anyway.

Back to the tea.  The taste range also reminds me of aromatic root spices; I suppose it had been like that in earlier infusions, and also it's moving more in that direction.  I wish I could name which ones.  Ginger smells nothing like it, and ginseng doesn't have that much smell.  I want to say "sassafrass" but I may have never actually tried a sassafrass infusion.  The trees grew around our house when I was young, and as I recall even the leaves gave off a really nice scent when broken.  I was a strange kid; I climbed trees a lot, smelled a lot of plants, and played with mud a good bit too.  Even as an adult while hiking in Colorado or Utah I'd crush bits of sage or pine needles to smell.


That one aspect is not completely unlike star anise but it's as wispy and faint in this expression as that spice is typically intense and overpowering, so the opposite, related to a typical level and overall effect.  Along those same lines a sweet version of autumn leaf also matches.  It's woody, but not necessarily in the same sense I usually mean by that.  Typically I experience wood as either a dark wood, more common in Wuyi Yancha, or a cedar-like aromatic wood, but this is more like how stacks of wood set aside for winter use back home would smell, sweet and complex, light in one sense, but with some different scent range going on.


It might seem odd that I'm describing all those as "narrow in range."  The general effect is comparable to that of an aged shou mei, it seems to me, even if the aspects aren't a perfect match, they just overlap a good bit.  It's warm, soft, sweet, earthy, and a bit complex but also subtle.  I would hope that some people into shou mei completely get what I'm talking about.  I was expecting something else; a much earthier, more intense, rocks, leather, and tree bark sort of tea, maybe even with a challenging, funky edge to it.  I'm not disappointed that it's subdued and approachable, it's just not what I expected.

blog mascots, camping inside the house

Post-script; two other bloggers talk about Fu zhuan (brick) tea

I remember reading about one of my favorite tea bloggers, Amanda of My Thoughts are Like Butterflies, trying Fu brick tea for the first time and being disappointed.  It reminds of a point that sort of goes without saying about trying this one:  I'm not reviewing the type of tea in general, I'm passing on an impression of this one version.  If you tried one Anxi Tie Kuan Yin or one Wuyishan Da Hong Pao and judged the type by that tea you might love that type or hate it for all the wrong reasons.  To me that works better for the DHP than the TKY since those really do vary so much in character, but the intense, sweet floral aspects range that make Tie Kuan Yin so appealing don't appear in all of the quality range of versions.  Bad DHP really can taste like cardboard, in the bad sense, so that's a different thing.


Amanda's blog post description is interesting:

I am going to just lay it all on the table, I do not like this tea, at all. I am not sure if there is something wrong with the tea (having never had it before, though I do have a different sample of a Fu Zhuan to try now sitting on my desk, convenient timing on that one) or if I just do not like it, so I cannot judge it on quality. Doing a little research on Fu Zhuan, it is said that the taste will connect you to the element of Earth in Chinese Medicine, personally I think I got kicked in the face by an angry Ent trying to impart lots of the element of Wood. It tastes like drinking mulch water (yes, I do know EXACTLY what that tastes like) mixed with leather and that same odd taste you get from chewing on the collar of your cotton shirt (and yes I know what that tastes like too, I was a chewer once upon a time) there is a touch of sweetness at the finish that reminds me of pine loam, that part I liked, but the woody and almost cardboard like aftertaste killed it for me.


I'm going to miss new versions of that rambling coming out, since she let tea blogging go, at least for now.  It's odd I added that after making up the earlier description and we both mentioned cardboard, as positive and negative.

Earlier descriptions in her post had mentioned wood, mulch, and leaves, so kind of the same range I'm experiencing in this other tea, although this version seems to have included more fruit and spice.  I wonder how similar they are, and to what extent a difference in preferences shifts impression versus the teas being different.  Sometimes it really just takes that one narrow bit of aspect range to make a tea really work or really not, some spice or mustiness to tip a tea towards working or not working, although from the sounds of it she may just not be on that general page.

After reading that, through the power of suggestion, or just helping bring a flavor to the light of description, a very faint touch of pine seems present.  As with the trace of star anise-like spice it's odd experiencing that at such a low intensity; it's not how those particular flavors tend to work.  I also just tasted my shirt; maybe the tea is not like that, although I'm not getting much flavor out of it.


I really liked the tea.  It probably didn't hurt that I was just drinking a Hunan brick tea, and a lighter, sweeter shou pu'er, and that I went through a shou mei phase earlier in the year to keep moving into that range.  And I loved a compressed black tea that went in a similar direction.  I could imagine people being on lots of different pages that would relate to not liking it as much as I did.

While I'm citing other inputs, another description by the Oolong Owl blogger went into more about the effect of a related version of tea, experienced at the 2017 World Tea Expo:


Cwyn waved me over to the Xixianxinqu Jinye Fucha Tea booth, and displayed was a wrapped 2 kilo brick and samples of clear golden tea. I was told it was fu zhuan tea, aka fermented tea with purposefully grown golden mold.  We didn’t have an open example, but was assured it was full of golden flowers.

I don’t recall how many cups I had. One? Two? It was delicious, honey, and sweet. Immediately I felt like a thousand ants were crawling on me and my head was filled with stuffing. I also would fail a sobriety test as I could not walk straight, began to chatter and laugh too much. I completely lost my usual professional routine of doing the World Tea Expo and stumbled through the show floor in a random manner, cursing fu bricks as I went. I had to piece much of this day by photos I took.


I'm quite a few cups into this tea--ten?  funny it's not fading more--and not noticing anything.  Maybe I'd need to be out in public to get the full effect, at a tea convention, or at least to walk into a 7-11.

Fluoride in tea; a summary version

Originally posted as:  www.tching.com/2017/08/fluoride-level-risk-tea/


I recently researched the risks of fluoride in tea for a blog post, after a group discussion raised the issue.  To be clear, the probable risk is low.  I'll return to special cases where there might be real risks after filling in some basics.

Editor's note:  that earlier article went through more related to possible health risks, factors relating to fluoride levels in tea, particularly related to the age of leaves used (bud and first two leaves versus "lower" leaves, which are higher in fluoride content), and calculations related to assessing intake.  This article version is a shorter summary.


Fluoride is a positive dietary input found in tea, recognized as helping prevent teeth decay, and cited as one form of treatment for osteoporosis (a WebMD reference to that, and some general background).  But any dietary or supplementary inputs are beneficial or harmful within a limited range, and the focus here is on risks related to too much.

Basics related to Fluoride intake

-The earlier EPA recognized limit for fluoride daily intake was 10 mg / day.

-That was revised  to .08 mg fluoride / kg (body weight) / day.  Since I weigh 70 kilograms (155 pounds) 5.6 mg / day of fluoride is the long term limit.


See an EPA Questions and Answers on Fluoride reference and FLUORIDE IN DRINKING WATER: A Scientific Review of EPA’s Standards for more background.


-The treatment level of fluoride (added to municipal water) is .7 to 1.2 mg / liter (or ppm, parts per million; they work out to mean the same thing).

-Since fluoride occurs naturally in some water sources (wells or springs; it is just another mineral) the EPA sets a limit for a maximum.  They now recommend municipal water sources should contain no more than 2 mg / liter (a revised guideline), with a mandatory regulated limit of 4 mg / liter.

-Some natural water sources can contain over 10 mg / liter, although that is relatively rare.

Naturally occurring fluoride levels chart, places over 1.5 mg/liter supplement levels (source credit)

Fluoride in tea

 An Indian research paper provides a great starting point for amounts of fluoride in brewed teas:

That amount varies from 1 mg / liter up to around 3.5 mg / liter.


This table shows amounts of fluoride in different Chinese teas measured as amounts in milligrams per kilogram of dry tea (from "Fluoride Content in Tea and Its Relationship With Tea Quality"):

A bit of interpretation is required.  I do a lot more with the numbers and calculations in that earlier post but we can estimate brewed tea amounts from this, after some assumptions:


-50 to 100 mg fluoride / kg of tea are considered as low and high levels

-each cup of brewed tea is based on two grams of dry tea (not a given, but making 2 cups of tea using 4 grams of dry tea is within the standard range).  Essentially complete extraction is assumed here, not really a given in actual practice.


50 mg / kg tea * 2 gm of tea per cup * 1 kg of dry tea / 1000 grams =

.1 mg / cup of tea (or .2, based on the "100" value; up to .4, based on the very highest "200" range)


Sounds like not much.  Even if those are 6 ounce cups of tea it still only works out to 1.1 mg / liter on that higher "100 mg / kg" calculation (for over five cups of tea):

This estimation matches the Indian study relatively well (1-3.5 mg / liter of tea), with a range up to 2.2 mg / liter using that highest "200" value instead.

Additional thoughts / conclusions

Based only on the amount of fluoride in water there is almost no risk.  Drinking two liters of water a day treated to 1.2 mg / liter (the highest treatment level) adds up to 2.4 mg; well below either limit of 5 or 10 mg / day.  The recommended EPA city water maximum limit of 2 mg / day brings that to 4 mg / day (and the mandatory treatment level to double that, giving alarmists something to talk about, since that is a bit high).


Based only on normal consumption of relatively high amounts of tea (two liters per day) there is very little risk.  Even at the very highest level those totals don't exceed 7 mg / day, for the Indian study values, or 4.4 mg / day for the highest Chinese version.  But then averaging drinking two liters of tea per day really is a lot; that's a bit over eight 8-ounce cups of tea.


The obvious case when there could be some limited risk:  when both add up.  Preparing two liters of tea per day from fluoride treated water really could relate to an intake of 2.4 + 4-7 mg / day, on the highest side a good bit above the maximum long term intake for someone of my weight (5.6 mg / day), approaching the older recognized limit of 10 mg / day.


Other special cases:  high levels in natural water sources, or due to a recreational runner or construction worker drinking a lot of treated water.

more results from the earlier Chinese leaves study

Per online discussion there could be much higher risk related to some types of hei cha.  Those Indian study results seems to match that, with better teas relatively low in levels (more often based on two leaves and a bud plucking), with CTC teas made from other leaves.  Based on that other research there is potential for much higher fluoride levels for teas made using more of the oldest leaves.


My personal conclusion:  there is nothing to worry about, beyond those few special cases.


Editing note:  in reviewing a related issue I ran across the following reference for measured amounts in different teas, in the paper Assessment of fluoride concentration and daily intake by
human from tea and herbal infusions:

Some thoughts / interpretation:


-this matches the Indian tea study, with the general range of results of significantly under 1 mg / liter (starting at 1 mg / liter in that study, with the lowest range here roughly half that) up to over 3 mg / liter in some cases.

-a five or ten minute infusion time would match ordinary brewing practices; using a 30 minute brewing time is not typical.  For cases of cold brewing or brewing "grandpa style" (allowing tea to remain in contact with water) this higher level of fluoride extraction may result.

-lowest amounts are for buds-only or bud related teas, as expected (see the earlier related post).

-I hoped to review hei cha levels but they aren't included, except for pu'er, with those teas sampled all relatively low in fluoride level (.57 to 1.04 mg / liter based on 10 minute infusion time).

-oddly "Lipton" tea measured the second highest recorded level, and "Tetley Earl Grey" the third, after one outlier, Ygara Asta black tea.  Those Lipton and Tetley values are around the highest range for the Indian study (around 3 mg / liter), with the Ygara Astra in the range of double that (all varying by infusion time).