# bacteria danger from refilling water bottle?

**URL:** <https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858>\
**Category:** Factual Questions\
**Created:** [August 22, 2013, 5:01am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858 "2013-08-22T05:01:59Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![Mr\_Downtown](https://avatars.discourse-cdn.com/v4/letter/m/8e8cbc/32.png) [@Mr\_Downtown](https://boards.straightdope.com/u/Mr_Downtown)\
**Post date:** [August 22, 2013, 5:01am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/1 "2013-08-22T05:01:59Z")

</div>

I much prefer to drink carbonated/sparkling water, so sometimes I want to have a bottle with me. I keep a couple of old San Pellegrino bottles in the freezer, with about three ounces of water so I start out with a plug of ice in the bottom. I just pour some sparkling water in and put the bottle in my pack.

Sometimes when I get back from an outing I might delay up to a week getting around to pouring the water out, putting a little bit of fresh tap water in, and then putting it in the freezer. It occurs to me that there might be bacterial growth in the bottle from backwash or other sources, and I don’t know if the cursory rinsing or the freezing takes care of that.

It isn’t practical to wash these bottles in the dishwasher or even very hot water from the sink, as the plastic will deform.

Part of me reasons that canteens don’t have any history of causing problems, including the many canteens used in the millennia prior to discovery of bacteria.

---

<div class="post-metadata">

**Author:** ![Peanuthead](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peanuthead/32/360_2.png) [@Peanuthead](https://boards.straightdope.com/u/Peanuthead)\
**Post date:** [August 22, 2013, 5:16am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/2 "2013-08-22T05:16:33Z")

</div>

I think you answered your own question in the last sentence. After all, you don’t use a brand new toothbrush every day do you? Samo -samo.

---

<div class="post-metadata">

**Author:** ![Bob\_Blaylock](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_blaylock/32/3235_2.png) [@Bob\_Blaylock](https://boards.straightdope.com/u/Bob_Blaylock)\
**Post date:** [August 22, 2013, 6:23am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/3 "2013-08-22T06:23:08Z")

</div>

If all you are putting in the container is water, then you shouldn’t have much of a problem. It’d be a good practice to wash the bottles out every so often, but I wouldn’t worry. Bacteria won’t grow without some source of nourishment, of which plain water contains none.

If you were putting something in these bottles which contains sugar, or fat, or some other nutritive component—say broth or non-diet soda, or fruit juice—it’d be a different matter.

---

<div class="post-metadata">

**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\
**Post date:** [August 22, 2013, 6:26am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/4 "2013-08-22T06:26:11Z")

</div>

We re-use water bottles perpetually till they get lost, just washing them in between. You must machine dishwash or handwash at an extraordinarily high temperature: we’ve never found distortion of plastic bottles to be a problem.

---

<div class="post-metadata">

**Author:** ![PSXer](https://avatars.discourse-cdn.com/v4/letter/p/48db29/32.png) [@PSXer](https://boards.straightdope.com/u/PSXer)\
**Post date:** [August 22, 2013, 6:27am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/5 "2013-08-22T06:27:32Z")

</div>

I read somewhere that re-using plastic bottles can cause cancer since it release plastic toxins into the water

---

<div class="post-metadata">

**Author:** ![tellyworth](https://avatars.discourse-cdn.com/v4/letter/t/977dab/32.png) [@tellyworth](https://boards.straightdope.com/u/tellyworth)\
**Post date:** [August 22, 2013, 6:44am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/6 "2013-08-22T06:44:16Z")

</div>

You might want to [wash them](http://foodsafety.k-state.edu/en/news-details.php?a=4&c=30&sc=218&id=27844) from time to time.

> [@](#):
>
> Cathy Ryan, a groundwater contamination scientist at the University of Calgary and one of the study’s authors, was cited as saying that the analysis showed the water in many of the bottles was so tainted that if it were from a municipal water supply, a boil-water order would be issued, adding, “It was not drinkable water. It certainly is not appropriate in terms of public health.”

---

<div class="post-metadata">

**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\
**Post date:** [August 22, 2013, 6:55am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/7 "2013-08-22T06:55:26Z")

</div>

> [@PSXer](#):
>
> I read somewhere that re-using plastic bottles can cause cancer since it release plastic toxins into the water

I read somewhere that dihydrogen monoxide was toxic. There is a lot of scaremongering BS out there.

---

<div class="post-metadata">

**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\
**Post date:** [August 22, 2013, 7:02am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/8 "2013-08-22T07:02:52Z")

</div>

> [@tellyworth](#):
>
> You might want to [wash them](http://foodsafety.k-state.edu/en/news-details.php?a=4&c=30&sc=218&id=27844) from time to time.

What always amuses me about studies or articles like that is that they are full of “ZOMG!!! Bacteria!!!” scaremongering but totally fail to notice the obvious, namely that if the objects are All Dreadfully Contaminated but the people using them aren’t actually getting sick, then perhaps they need to think a bit harder about whether their findings are actually important instead of making alarmist pronouncements and feeding germophobic hysteria.

---

<div class="post-metadata">

**Author:** ![SeaDragonTattoo](https://avatars.discourse-cdn.com/v4/letter/s/df705f/32.png) [@SeaDragonTattoo](https://boards.straightdope.com/u/SeaDragonTattoo)\
**Post date:** [August 22, 2013, 7:17am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/9 "2013-08-22T07:17:21Z")

</div>

I have a water canteen/bottle I use at work, that I keep at work, and have never done more than rinse and let air dry. It’s been a couple of years now. I must be dead.

---

<div class="post-metadata">

**Author:** ![JBDivmstr](https://avatars.discourse-cdn.com/v4/letter/j/b4bc9f/32.png) [@JBDivmstr](https://boards.straightdope.com/u/JBDivmstr)\
**Post date:** [August 22, 2013, 8:42am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/10 "2013-08-22T08:42:43Z")

</div>

> [@PSXer](#):
>
> I read somewhere that re-using plastic bottles can cause cancer since it release plastic toxins into the water

Seriously? And… you _believe_ that? :rolleyes:

> [@Princhester](#):
>
> I read somewhere that dihydrogen monoxide was toxic. …

Absolutely DEADLY, it is! 😉  
Why, it _KILLS_ untold numbers of people _ **every day** _, all over the world! :eek:  
It needs to be _ **OUTLAWED** _, I tells you! 😛

---

<div class="post-metadata">

**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\
**Post date:** [August 22, 2013, 11:57am UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/11 "2013-08-22T11:57:54Z")

</div>

> [@SeaDragonTattoo](#):
>
> I have a water canteen/bottle I use at work, that I keep at work, and have never done more than rinse and let air dry. It’s been a couple of years now. I must be dead.

I had an old 20-ounce pepsi bottle that I refilled with water from the drinking fountain at work for several years. I never got sick, though the interior of the bottle did become horribly yellowed and crusty over time. It wasn’t rock-hard calcium carbonate deposits from evaporation, it was semi-soft crud that could be scraped from the inside of the bottle with a fingernail or paper towel, so I’m assuming it was some kind of bacterial mat. Wikipedia makes reference to [“extracellular polymeric substance,”](http://en.wikipedia.org/wiki/Extracellular_polymeric_substance) a material that bacteria deposit to help them form an enduring biofilm; that sounds about right.

Whatever bacterial colonies may have existed in that water bottle, they don’t appear to have been injurious to my health. Nonetheless, my wife was disgusted when she saw that bottle one day and insisted on replacing it with a [Camelbak Eddy bottle.](http://shop.camelbak.com/eddy-75l/d/1012_cl_3300) I’ve had this for a couple of years now, and the interior has no visible evidence of bacteria; my guess is that the bite valve and straw eliminate backwash, minimizing the potential for introducing bacteria, saliva and biological material into the bottle.

As I examine it now though, the inside of the bite valve _does_ appear to be getting crusty. Maybe time for a wash…😃

---

<div class="post-metadata">

**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\
**Post date:** [August 22, 2013, 12:00pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/12 "2013-08-22T12:00:09Z")

</div>

I re-use plastic bottles. Since I don’t have a mechanical dishwasher (just my two hands) I occasionally subject them to a bleach rinse, particularly if they had something other than water in them.

[This](http://www.ehow.com/how_5744461_wash-dishes-chlorine-bleach.html) is a quick how-to link. You don’t actually need the pH strips, there’s some wiggle room, just follow the measuring instructions. Bleach kills germs even in cold water.

---

<div class="post-metadata">

**Author:** ![excavating\_for\_a\_mind](https://avatars.discourse-cdn.com/v4/letter/e/e8c25b/32.png) [@excavating\_for\_a\_mind](https://boards.straightdope.com/u/excavating_for_a_mind)\
**Post date:** [August 22, 2013, 12:32pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/13 "2013-08-22T12:32:12Z")

</div>

> [@SeaDragonTattoo](#):
>
> I have a water canteen/bottle I use at work, that I keep at work, and have never done more than rinse and let air dry. It’s been a couple of years now. I must be dead.

This is all that is really necessary. As long as the inside is clean, a rinse and air dry is all that is needed. Bacteria need moisture to survive, if it is dry, those suckers ain’t gonnna live long.

You do have to keep the inside clean, however. Buildup of dirt, scale, deposits, etc, will hold water, preventing it from getting dry.

Now, there are spores and other critters that can survive a dry environment, but these things need a food source. If all you are going to put in there is water, even if there are a few (dry) mold spores and/or yeast cells present, just getting them wet (with no source food) isn’t going to allow them to do much. You have much worse growing in your mouth.

---

<div class="post-metadata">

**Author:** ![Uber\_the\_Goober](https://avatars.discourse-cdn.com/v4/letter/u/58956e/32.png) [@Uber\_the\_Goober](https://boards.straightdope.com/u/Uber_the_Goober)\
**Post date:** [August 22, 2013, 1:26pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/14 "2013-08-22T13:26:12Z")

</div>

> [@PSXer](#):
>
> I read somewhere that re-using plastic bottles can cause cancer since it release plastic toxins into the water

Why do you post to GQ?

Stop it. Your stupid is showing. At least scratch up a cite or something…

---

<div class="post-metadata">

**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\
**Post date:** [August 22, 2013, 1:55pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/15 "2013-08-22T13:55:45Z")

</div>

> [@Uber\_the\_Goober](#):
>
> Why do you post to GQ?
> 
> Stop it. Your stupid is showing. At least scratch up a cite or something…

**Moderator Warning**

**Uber\_the\_Goober** , you’ve been around long enough to know that insults are not permitted in GQ. This is an official warning. Don’t do this again.

Colibri  
General Questions Moderator

---

<div class="post-metadata">

**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\
**Post date:** [August 22, 2013, 2:12pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/16 "2013-08-22T14:12:13Z")

</div>

> [@Princhester](#):
>
> I read somewhere that dihydrogen monoxide was toxic. There is a lot of scaremongering BS out there.

I do my best to get rid of that shit. But I swear, every time I refill the bottle it re-appears immediately.

---

<div class="post-metadata">

**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\
**Post date:** [August 22, 2013, 2:52pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/17 "2013-08-22T14:52:14Z")

</div>

> [@PSXer](#):
>
> I read somewhere that re-using plastic bottles can cause cancer since it release plastic toxins into the water

I’ve run across this far-fetched idea several times recently. What the believers can’t seem to explain is how the toxins know not to leak into the original water, but to wait until the bottle is refilled.

---

<div class="post-metadata">

**Author:** ![jasg](https://avatars.discourse-cdn.com/v4/letter/j/f0a364/32.png) [@jasg](https://boards.straightdope.com/u/jasg)\
**Post date:** [August 22, 2013, 2:59pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/18 "2013-08-22T14:59:47Z")

</div>

> [@panache45](#):
>
> I do my best to get rid of that shit. But I swear, every time I refill the bottle it re-appears immediately.

DiHydrogen Monoxide is an insidious and universal contaminant of most drinks…I hate it when it sneaks into my scotch.

Regarding toxic plastic bottles, [Snopes](http://www.snopes.com/medical/toxins/plasticbottles.asp) is our friend again.

---

<div class="post-metadata">

**Author:** ![shijinn](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@shijinn](https://boards.straightdope.com/u/shijinn)\
**Post date:** [August 22, 2013, 3:20pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/19 "2013-08-22T15:20:57Z")

</div>

Wiki says one-use polyethylene terephthalate (PET) bottles will leech Antimony. the levels may not be hazardous but there it is.

---

<div class="post-metadata">

**Author:** ![Rachellelogram](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rachellelogram/32/8689_2.png) [@Rachellelogram](https://boards.straightdope.com/u/Rachellelogram)\
**Post date:** [August 22, 2013, 6:40pm UTC](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858/20 "2013-08-22T18:40:20Z")

</div>

> [@PSXer](#):
>
> I read somewhere that re-using plastic bottles can cause cancer since it release plastic toxins into the water

Please define what a “toxin” is, and which one inhabits water bottle plastic.

[Next page](https://boards.straightdope.com/t/bacteria-danger-from-refilling-water-bottle/666858.md?page=2)
