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.
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.
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.
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.
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,” 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. 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…
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 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.
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.
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.
