# are there water-borne illnesses that cannot be stopped by boiling drinking water? **URL:** \ **Category:** Factual Questions\ **Created:** [June 12, 2011, 10:35pm UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255 "2011-06-12T22:35:56Z")\ **Posts on this page:** 13\ **Page:** 2
**Author:** ![brocks](https://avatars.discourse-cdn.com/v4/letter/b/7feea3/32.png) [@brocks](https://boards.straightdope.com/u/brocks)\ **Post date:** [June 14, 2011, 5:39am UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/21 "2011-06-14T05:39:08Z")
I live on the central Oregon coast, and a small town near me has had trouble with some kind of algae bloom in its reservoir for the last few summers. During those times, residents are advised to use bottled water, and are specifically told that boiling does not make the water safe to drink. I have no idea what is in the water that boiling won’t fix, or even if the warning is valid, but that’s what the official announcements on the radio say. ---
**Author:** ![Telemark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/telemark/32/372_2.png) [@Telemark](https://boards.straightdope.com/u/Telemark)\ **Post date:** [June 14, 2011, 6:54am UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/22 "2011-06-14T06:54:21Z")
> [@Son\_of\_a\_Rich](#): > > That would be one super pathogen what could survive 15 minutes of boiling. :eek: At altitude the boiling point of water is lower so you may need to boil for longer at a lower temp to get the same effect. At 4000 meters the boiling point is only around 190 F. ---
**Author:** ![phouka](https://avatars.discourse-cdn.com/v4/letter/p/c5a1d2/32.png) [@phouka](https://boards.straightdope.com/u/phouka)\ **Post date:** [June 14, 2011, 7:23am UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/23 "2011-06-14T07:23:30Z")
I’m relieved to read on Wiki that cryptosporidium is most reliably killed by boiling, so there’s that, at least. ---
**Author:** ![AaronX](https://avatars.discourse-cdn.com/v4/letter/a/7bcc69/32.png) [@AaronX](https://boards.straightdope.com/u/AaronX)\ **Post date:** [June 14, 2011, 11:52am UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/24 "2011-06-14T11:52:37Z")
> [@Canadjun](#): > > According to [Wikipedia](http://en.wikipedia.org/wiki/Toxin), a toxin (Greek: τοξικόν, toxikon) is a poisonous substance produced by living cells or organisms, so something like arsenic or mercury would not be a toxin (but would be a poison). But methylmercury is produced by organisms. What about prions? I think they’re heat resistant. ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [June 14, 2011, 2:31pm UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/25 "2011-06-14T14:31:32Z")
[Hyponatremia](http://en.wikipedia.org/wiki/Hyponatremia)? ---
**Author:** ![Ferret\_Herder](https://avatars.discourse-cdn.com/v4/letter/f/e47774/32.png) [@Ferret\_Herder](https://boards.straightdope.com/u/Ferret_Herder)\ **Post date:** [June 14, 2011, 4:06pm UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/26 "2011-06-14T16:06:48Z")
> [@brocks](#): > > I live on the central Oregon coast, and a small town near me has had trouble with some kind of algae bloom in its reservoir for the last few summers. During those times, residents are advised to use bottled water, and are specifically told that boiling does not make the water safe to drink. Check the link above on the dangers of cyanobacteria; it’s the scientific term for blue-green algae. ---
**Author:** ![Wizard\_One](https://avatars.discourse-cdn.com/v4/letter/w/6a8cbe/32.png) [@Wizard\_One](https://boards.straightdope.com/u/Wizard_One)\ **Post date:** [June 15, 2011, 5:55pm UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/27 "2011-06-15T17:55:58Z")
> [@AaronX](#): > > But methylmercury is produced by organisms. What about prions? I think they’re heat resistant. Prions are resistant to heat. There are a handful of proteins that won’t denature with heat as well. Some toxins won’t degrade with reasonable heating either, such as urushiol, the wonderful chemical produced by poison ivy and its cousins, which survives even being put into a fire (every couple of years, someone burns poison ivy and either injures themselves or others from the vapor from the plants, frequently with fatal results). That said, for most uses, boiling water SHOULD render it safe, save for those toxic blooms and chemical contamination. The vast majority of pathogens, if not killed outright, are dormant and would be unable to colonize your body. Of course, the most reliable method, a method tens of thousands of years old, is to not drink the water at all, use it to make beer, the yeast would kill off the pathogens, rendering the beer safe to drink. 🙂 ---
**Author:** ![Wizard\_One](https://avatars.discourse-cdn.com/v4/letter/w/6a8cbe/32.png) [@Wizard\_One](https://boards.straightdope.com/u/Wizard_One)\ **Post date:** [June 15, 2011, 6:04pm UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/28 "2011-06-15T18:04:47Z")
> [@Sailboat](#): > > [Hyponatremia](http://en.wikipedia.org/wiki/Hyponatremia)? What is the relevance of a lack of salt in the body to the OP? ---
**Author:** ![Susanann](https://avatars.discourse-cdn.com/v4/letter/s/7ab992/32.png) [@Susanann](https://boards.straightdope.com/u/Susanann)\ **Post date:** [June 15, 2011, 6:29pm UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/29 "2011-06-15T18:29:34Z")
> [@aceplace57](#): > > May have been unwashed berries, the water or who knows what. Why would an unwashed berry, from the wild, make anybody sick? I have eaten lots of wild berries over the decades and never got sick from a wild berry. Seems to me a wild berry is inherently clean. ---
**Author:** ![Canadjun](https://avatars.discourse-cdn.com/v4/letter/c/76d3ee/32.png) [@Canadjun](https://boards.straightdope.com/u/Canadjun)\ **Post date:** [June 16, 2011, 12:26am UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/30 "2011-06-16T00:26:47Z")
> [@Wizard\_One](#): > > What is the relevance of a lack of salt in the body to the OP? I’m guessing he is referring to the ultimate in a “water-borne illness”, namely drinking too much water. I understand one of the most important effects of ODing on water itself is hyponatremia, i.e. ODing on water causes critically low sodium levels. ---
**Author:** ![brocks](https://avatars.discourse-cdn.com/v4/letter/b/7feea3/32.png) [@brocks](https://boards.straightdope.com/u/brocks)\ **Post date:** [June 16, 2011, 1:14am UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/31 "2011-06-16T01:14:52Z")
> [@Susanann](#): > > Why would an unwashed berry, from the wild, make anybody sick? Maybe a bird shit on it, and rain washed enough off of it to make it hard to see. ---
**Author:** ![Susanann](https://avatars.discourse-cdn.com/v4/letter/s/7ab992/32.png) [@Susanann](https://boards.straightdope.com/u/Susanann)\ **Post date:** [June 16, 2011, 2:18am UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/32 "2011-06-16T02:18:46Z")
> [@brocks](#): > > Maybe a bird shit on it, and rain washed enough off of it to make it hard to see. 1 in a million shot ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [June 16, 2011, 5:39pm UTC](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255/33 "2011-06-16T17:39:27Z")
> [@Wizard\_One](#): > > What is the relevance of a lack of salt in the body to the OP? Well, I was joking, because the usual place one encounters hyponatremia in the news is in stories of people who died after drinking too much water, usually while participating in marathons or the like. Pre-boiling the water obviously would not prevent the illness. However, regarding “lack of salt” – note the last line in this passage from the Wikipedia article I cited: > [@](#): > > Hyponatremia is most often a complication of other medical illnesses in which excess water accumulates in the body at a higher rate than can be excreted (for example in congestive heart failure, syndrome of inappropriate antidiuretic hormone, SIADH, or polydipsia). Lack of sodium is virtually never the cause of hyponatremia… [Previous page](https://boards.straightdope.com/t/are-there-water-borne-illnesses-that-cannot-be-stopped-by-boiling-drinking-water/585255.md?page=1)