I'm 99% sure that any boiling will kill nearly all germs in water. I don't have facts on hand, but I do remember that once you get above ~160F, nearly all germs are dead. So boiling water will definitely kill everything.
That's a pressure issue, though - low air pressure drops boiling temperature, so your water doesn't actually get as hot. Most commercial aircraft are pressurized to around 11psi, which is an elevation of ~3,500 feet.
It will kill the pathogens which cause vomiting and diarrhea: the article mentions e. coli, which the CDC[0] recommend 1 minute at boiling temperature to deactivate. I'd skip that and stop as soon as the water boiled.
Note that sterilization requires higher temperatures for longer periods, but it's not required for food products consumed by the general public. Some bacteria may survive the boiling process, but your stomach acid + immune system will destroy them.
Good point! That's why posting on HN is so great, even if you're 99.9% correct, someone will always reply to tell you precisely how you are 0.1% wrong . Thanks for the link, I tried to find official sources online and had trouble.
To be clear, I think your original comment is just fabulous and you're 100% right.
I'm just curious since I know that controlling the level of E. coli contamination in milk is important from first-hand work on dairy farms, plus I know that pasteurization heats (not boils) the milk, and not for the ridiculous durations I see when searching online for "making water safe to drink".
Also, the relevant factor is not just temperature--it's a combination of time and temperature. For milk, you can do 1-2 seconds at 135C (UHT), 15 sec at 72C (HTST), or something like 20 min at 60C.
Cruising altitude on a plane is roughly equivalent to air pressure at 1800-2400m, so using [1] that means water boils at around 93°C.
(If I had any familiarity with Fahrenheit, I wouldn't have bothered looking this up. 160°F = 70°C, and even on Everest water boils at a higher temperature.)
> I'm 99% sure that any boiling will kill nearly all germs in water. I don't have facts on hand, but I do remember that once you get above ~160F, nearly all germs are dead. So boiling water will definitely kill everything.
Occasionally I find out that something that I thought / hoped / believed to be the case ... wasn't.
Killing 'nearly all germs' is good, but not really what you need when you may get sick or die from the kinds of germs that don't fit the 'nearly all' category.
Cryptosporidium and giardia (two things that Sydney residents became overly familiar with before our Olympic hosting) require a few minutes of rolling boil to kill. And the definition of 'rolling boil' becomes more onerous as you increase your altitude.
> I'm 99% sure that any boiling will kill nearly all germs in water.
CDC says a full minute of boiling (3 minutes for elevations greater than 6,500ft) to deal with (the problem strain of) E. coli in well water. Momentary boiling is not sufficient for safety.
I think to kill all bacteria you need to boil for several minutes. A typical tea kettle turns off immediately after reaching the boiling point. Coffee is a similar story I guess.
Right...to actually sterilize something, you have to hold it well above boiling. Autoclaves run at high pressure so they can get liquids up to 121C.
However, you don't need sterile food; you just need to ensure that there are sufficiently few bacteria that your body can deal with the rest. I would suspect boiling water (to make the coffee) and holding it hot (for serving) helps quite a bit with this, but I was wondering if anyone had some actual numbers.
I guess the question is exactly what's in the water.
Sterilizing river water calls for one minute at a rolling boil, which you won't get from a kettle. But something like beef, with a much more restricted threat, can be done down around 160F, and bringing your kettle to a boil should easily get you a few minutes above that line.
Not all tea brewings will, but I'm guessing "boil it and throw in tea" is more common on airplanes than a delicate, 165F green tea production.
So... it'd be nice to hear from a microbiologist about the specifics on this one. Regulators seem concerned, but that's about drinking it as tap water, which I wouldn't do.
That's the point of the article. Drinking water is from bottled water. Hot beverages are from the 'tap' water, and the requirements on the tap water are not as strict as the drinking water.
I assume that this is a just alarmist journalism, since water for tea/coffee is heated to boiling, and all the taps in the bathrooms say some version of 'non-potable'.
> I assume that this is a just alarmist journalism, since water for tea/coffee is heated to boiling ...
Boiling at elevation is different to boiling at sea level.
To kill Cryptosporidium (etc) you need a rolling boil for 1 minute (no one does this) ... and that's at sea level. At > 2km up you need to run that for > 3 minutes (and absolutely no one does that).
And all this is before I even get started on the woefully uncivilised idea of using 100C water for green tea.
You're absolutely correct. I should have been clearer.
When I mentioned the >2km 'elevation' I meant in an airplane, which typically cruises around 10km ... but are pressurised, as you note. Unfortunately they're pressured to be around 2.4km (effective). Some newer planes will pressurise to around 1.8km but these are uncommon.
In any case, water boils at '2.4km effective' at around 92C ... and therein lies the problem.
I never know what to take away from these "germs are everywhere" scare stories. I've been drinking coffee on planes for years. Maybe I've been exposed to something, but I've never been sick. Maybe it's making my immune system stronger. I'll make reasonable choices but I'm not going to be paranoid or even think twice about something like coffee on an airplane.
I was initially concerned, expecting a "heavy metals" story. Those are also common, but they're a bit less overhyped, and do predictable, cumulative harm. A vague threat of E. Coli just isn't as disturbing to me.
The water is boiled to thermo-nuclear levels so I'd be shocked if anything nasty could survive it - certainly the flavor can't!
I'm not sure if it's because there's more content available these days, but the "germs are everywhere" movement has far greater prominence than when I grew up. We'd spend all summer barefoot, put our hands in places they shouldn't and then in our mouths, eat food that we almost certainly shouldn't have and yet we somehow survived.
There's some things that we absolutely shouldn't consume, but airplane tea and coffee are pretty low down that list.
It's potentially relevant to people who have compromised immune systems or who are on immunosuppressants.
Depending on when you grew up it is likely that those two groups are more prevalent, or at least are more likely to fly than before (think HIV and autoimmune disorders). But for most people the "germs are everywhere" thing is pretty overblown.
I get the sense people think we're cleaner than we really are. A great example are diseases like E. coli infections, campylobacter, hepatitis A, norovirus, cryptosporidium, etc. They are reasonably common and all are transmitted through the fecal-oral route. That is, the person getting sick ingested something contaminated with feces (human or animal).
Same thing with your own intestinal biome. You are sterile when you come out of your mother's womb. All of the bacteria that ends up in your intestine are ingested, often coming from your own family members.
Bacteria are everywhere. I'm not going to get overly worried about bacteria in the drinking water of planes unless it starts to make people sick.
> You are sterile when you come out of your mother's womb. All of the bacteria that ends up in your intestine are ingested, often coming from your own family members.
Is that so? I thought that fetuses shared some of their mother's intestinal flora, somehow.
The article -- unlike most articles of the "germs are everywhere" scare stories -- did say:
... people with a compromised immune system should steer clear of the in-flight beverage. He additionally noted that people with infants should “think twice” before filling a baby’s bottle with airplane tap water.
It's strange... I've always assumed that airplane coffee is the lowest of the low-bid, el-cheapo, nobody-else-would-buy-this coffee that you could find. But yet, I've always enjoyed the coffee on airplanes, and to a surprising degree. I think every time I've ever gotten coffee on an airplane, my thought after the first sip was "OMG, that is SO good".
But, that could just be because I'm usually dead-tired, caffeine deprived, and jonesing for coffee like a crack addict craving their next hit, by the time I get on the plane. shrug
Damn near every flight I see the pilot and copilot enjoy a cup of coffee, and yet we don't hear about the waves of moribund pilots unable to perform their duties....
If you're paying attention you'll notice that, typically after cabin beverage service ends, the flight attendants will make and deliver coffee to the cockpit. What happens to that coffee once it's behind the door is, of course, purely speculation.
I see the pilot (or co-pilot) during at least 50% of the flights I take in the US over two hours in flight time. If you've noticed a FA blocking the aisle to the galley with a drink cart and standing posted at attention watching the passengers attentively, that's why. The cockpit door is rarely open more than 15-30 seconds. If either of the cockpit crew actually leaves the cockpit (say to use the restroom), then a FA must take their place and relock the door. This scenario requires a minimum of two FAs, one to watch the passengers / block the aisle, the other to fill-in in the cockpit.
What! Companies still use manned cockpits nowadays? It's a bit like letting a guy into the server room: Pilot error is the cause of 75%[1] plane crashes (Of course I'm kidding, the pilot is probably the cause of non-crashing 99.99992% [2] of the flights).
On a slightly bumpy ride yesterday, the pilot told us not to worry: the only concern in the cockpit was that they might spill coffee on their white uniform shirts.
"According to a 2004 EPA sample of 158 planes, 13 percent contained coliform. Two of the airplanes were found to have dangerous E.coli in the water."
That is kinda gross, but realistically all that bacteria would be killed by heating the water.
More of a concern is that is the same tap water in the bathroom for washing hands. Last flight I took I noticed there was a Purell dispenser in the bathroom next to the sink and I wondered why that was necessary given there was soap and water.
The safe temperature for killing bacteria is about 140°F or 60°C. To get water to boil at that low a temperature requires about ⅕ atmospheric pressure, or roughly the atmospheric pressure outside the aircraft.
yea wilderness survival says full boil for at least 3 minutes, more in higher altitude. While shopping for an on-demand hot water tap, I couldn't find a single one that even went up to boiling temperature, so my hunch is that airplanes don't even boil for a second.
It depends on what you're trying to kill. Some bacteria perish quickly at less-than-boiling temperatures. In the wild, you have spores and other hardy organisms that require a lot more heat and time to kill.
The 3 minutes idea is to kill anything that may be deeply imbedded the bits of wood, leaves, and other detritus suspended in the water.
It's generally considered paranoid overkill when you consider the water will take a while to cool - it will stay in the "kill everything" temperature for quite a while in the process.
Heat absolutely does kill bacteria. Heating water for just a few minutes at 60C will kill e. coli, 70C will kill it instantly. Coffee is brewed at 90-100C.
If you've ever had coffee or tea on a plane, you probably already know that the water usually tastes terrible anyway. So, germs or no germs, stick to cold drinks. Like gin and tonic.
That's my philosophy. The Quinine will also help suppress any malaria one might catch due to humid conditions in the rear cabin toilets. Slice of lemon for a Vitamin-C immune system boost. The mild sedative of alcohol to drown out the screaming void of my mind left idle without access to the internet.
They cook the shit out of everything now cause everybody’s afraid of food poisoning! Hey, where’s your sense of adventure? Take a fucking chance will you? You know how many people die in this country from food poisoning every year? 9000... that’s all; it’s a minor risk! Take a fucking chance... bunch of goddamn pussies! Besides, what do you think you have an immune system for? It’s for killing germs! But it needs practice... it needs germs to practice on. So listen! If you kill all the germs around you, and live a completely sterile life, then when germs do come along, you’re not gonna be prepared. And never mind ordinary germs, what are you gonna do when some super virus comes along that turns your vital organs into liquid shit? I’ll tell you what you’re gonna do... you’re gonna get sick, you’re gonna die, and you’re gonna deserve it cause you’re fucking weak and you got a fucking weak immune system!
One really has to draw the hat to Business Insider pushing surprising insights: Long haul has more bacteria than short haul. I always thought bacteria would die off over time. /s
There is however a good chance coffee or tea messes with your sense of time so moderation when flying can be important. Especially when taking into account the beverages consumed of the ever increasing leg of the flight in the terminal.
Ummm... Pasteurization used to kill deadly bacteria in our food is done heating the substance to sanitize at 73-75 degree Celsius for around 15 seconds. For brewing a good coffee or tea you need a much higher temperature and I guess they don't immediately cool it down.
So, go ahead, drink your coffee or tea on the plane. Yes, it is disgusting, but it is a matter of taste, not of bacterial infection.
I take a can of V8, if they have it. A bit of nutrition and elctrolytes. If the water is a concern, then I guess it'll be a can of mineral water to go with it, instead of "tap".
I hate it when articles say "research found X in Y", without stating how much X there was and whether or not it is above normal level and is dangerous. It's California prop 65 story all over again. Bacteria are amazingly versatile and resilient, one can find _some_ of them practically everywhere, so finding some in an environment that is not specifically and thoroughly sterilized is no wonder. The question is how many of them and how dangerous that is to a common person. The article provides no information about it, and therefore is useless.
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[ 2.6 ms ] story [ 160 ms ] threadI've only ever seen bottled water for cold drinks as well, but I seriously doubt they're boiling bottles of Desani up front.
Note that sterilization requires higher temperatures for longer periods, but it's not required for food products consumed by the general public. Some bacteria may survive the boiling process, but your stomach acid + immune system will destroy them.
[0]: https://www.cdc.gov/healthywater/drinking/private/wells/dise...
I'm just curious since I know that controlling the level of E. coli contamination in milk is important from first-hand work on dairy farms, plus I know that pasteurization heats (not boils) the milk, and not for the ridiculous durations I see when searching online for "making water safe to drink".
Cruising altitude on a plane is roughly equivalent to air pressure at 1800-2400m, so using [1] that means water boils at around 93°C.
(If I had any familiarity with Fahrenheit, I wouldn't have bothered looking this up. 160°F = 70°C, and even on Everest water boils at a higher temperature.)
[1] http://docs.engineeringtoolbox.com/documents/1344/boiling_po...
Occasionally I find out that something that I thought / hoped / believed to be the case ... wasn't.
Killing 'nearly all germs' is good, but not really what you need when you may get sick or die from the kinds of germs that don't fit the 'nearly all' category.
Cryptosporidium and giardia (two things that Sydney residents became overly familiar with before our Olympic hosting) require a few minutes of rolling boil to kill. And the definition of 'rolling boil' becomes more onerous as you increase your altitude.
CDC says a full minute of boiling (3 minutes for elevations greater than 6,500ft) to deal with (the problem strain of) E. coli in well water. Momentary boiling is not sufficient for safety.
https://www.cdc.gov/healthywater/drinking/private/wells/dise...
However, you don't need sterile food; you just need to ensure that there are sufficiently few bacteria that your body can deal with the rest. I would suspect boiling water (to make the coffee) and holding it hot (for serving) helps quite a bit with this, but I was wondering if anyone had some actual numbers.
Sterilizing river water calls for one minute at a rolling boil, which you won't get from a kettle. But something like beef, with a much more restricted threat, can be done down around 160F, and bringing your kettle to a boil should easily get you a few minutes above that line.
Not all tea brewings will, but I'm guessing "boil it and throw in tea" is more common on airplanes than a delicate, 165F green tea production.
So... it'd be nice to hear from a microbiologist about the specifics on this one. Regulators seem concerned, but that's about drinking it as tap water, which I wouldn't do.
I assume that this is a just alarmist journalism, since water for tea/coffee is heated to boiling, and all the taps in the bathrooms say some version of 'non-potable'.
Boiling at elevation is different to boiling at sea level.
To kill Cryptosporidium (etc) you need a rolling boil for 1 minute (no one does this) ... and that's at sea level. At > 2km up you need to run that for > 3 minutes (and absolutely no one does that).
And all this is before I even get started on the woefully uncivilised idea of using 100C water for green tea.
When I mentioned the >2km 'elevation' I meant in an airplane, which typically cruises around 10km ... but are pressurised, as you note. Unfortunately they're pressured to be around 2.4km (effective). Some newer planes will pressurise to around 1.8km but these are uncommon.
In any case, water boils at '2.4km effective' at around 92C ... and therein lies the problem.
I'm not sure if it's because there's more content available these days, but the "germs are everywhere" movement has far greater prominence than when I grew up. We'd spend all summer barefoot, put our hands in places they shouldn't and then in our mouths, eat food that we almost certainly shouldn't have and yet we somehow survived.
There's some things that we absolutely shouldn't consume, but airplane tea and coffee are pretty low down that list.
Depending on when you grew up it is likely that those two groups are more prevalent, or at least are more likely to fly than before (think HIV and autoimmune disorders). But for most people the "germs are everywhere" thing is pretty overblown.
Flavour doesn't fare well with the dryness and low pressure of airplanes at altitude.
See e.g. http://www.bbc.com/future/story/20150112-why-in-flight-food-...
Same thing with your own intestinal biome. You are sterile when you come out of your mother's womb. All of the bacteria that ends up in your intestine are ingested, often coming from your own family members.
Bacteria are everywhere. I'm not going to get overly worried about bacteria in the drinking water of planes unless it starts to make people sick.
Is that so? I thought that fetuses shared some of their mother's intestinal flora, somehow.
A baby's intestinal flora is develop through ingestion of bacteria after birth. It generally comes from the mother.
Also, quite notably during birth.
... people with a compromised immune system should steer clear of the in-flight beverage. He additionally noted that people with infants should “think twice” before filling a baby’s bottle with airplane tap water.
But, that could just be because I'm usually dead-tired, caffeine deprived, and jonesing for coffee like a crack addict craving their next hit, by the time I get on the plane. shrug
Its times like this that I'm reminded of the risks of failing to fund high-quality investigative journalism...
[1] https://en.wikipedia.org/wiki/Pilot_error
[2] https://curiosity.com/topics/how-do-people-survive-plane-cra...
http://www.abc.net.au/health/talkinghealth/factbuster/storie...
http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-he...
That is kinda gross, but realistically all that bacteria would be killed by heating the water.
More of a concern is that is the same tap water in the bathroom for washing hands. Last flight I took I noticed there was a Purell dispenser in the bathroom next to the sink and I wondered why that was necessary given there was soap and water.
It's generally considered paranoid overkill when you consider the water will take a while to cool - it will stay in the "kill everything" temperature for quite a while in the process.
https://besurvival.com/guides/how-long-should-you-boil-water
[1] https://academic.oup.com/jtm/article-pdf/3/1/11/5107757/jtm3...
Also, there are lots of diseases such as E. coli infection, etc, that are food borne. Stomach acid doesn't seem to help all that much with those.
But you can't distribute weaponized fluids when your entire world is literally being rocked.
So they hand out lukewarm tea or coffee. Yes it is safe but not fit for human consumption.
Looks like they saved us from e.coli as well by giving us that tepid stuff.
In wine there is truth, in beer friendship, in water... bacteria.
Consider doing something with your mind...
-George Carlin
There is however a good chance coffee or tea messes with your sense of time so moderation when flying can be important. Especially when taking into account the beverages consumed of the ever increasing leg of the flight in the terminal.
So, go ahead, drink your coffee or tea on the plane. Yes, it is disgusting, but it is a matter of taste, not of bacterial infection.
https://www.washingtonpost.com/national/health-science/hyper...
/s