Every now and then, during the question period at the end of my talks, I get asked how long bottled water lasts and whether you can keep it past the expiration date; and I experience temporary panic. You see, I have typically kept my bottled water a year or two past the printed expiration date, because I’ve found it to be such a hassle to lug 14 gallons (in our case; 1 gallon per person per day for 7 days*) to a sink, empty them (it takes a LONG TIME), discard the jugs, and lug 14 more gallons from the store and individually bag them to put them on the shelf in our closet! I figure that even if it was unhealthy to frequently drink water that had been stored too long in plastic jugs, my emergency water is for an extremely rare event and I won’t mind a few days of it.
(*QuakePrepare.com recently pointed out that the Red Cross now suggests 14 days of supplies...but we don’t have enough space!)
However, I worry about giving this advice to people, because while I have felt that it is probably not a problem, I don’t know for sure. I would not want to counsel people to drink water that was potentially contaminated with leached chemicals. So, I answer that the expiration date on those gallon jugs typically gives you a year or two, and that I tended to over-store mine but this was not official advice and I could not guarantee that the water was healthy.
Well, yesterday I was reading a back issue of Consumer Reports (from October 2012), and they had a letter in their “ask our experts” column asking how long water should be used after purchase and whether the expiration date was meaningful. To my surprise, they said that the US Food and Drug Administration (FDA) considered bottled water to have an indefinite storage life as long as it was produced in accordance with regulations and was unopened. Let’s take a closer look at this, because not having to rotate out all this water would avoid a major hassle.
"In the U.S., bottled water and tap water are regulated by two different agencies; the FDA regulates bottled water and the U.S. Environmental Protection Agency (EPA) regulates tap water... FDA regulates bottled water as a food... Bottled water is considered to have an indefinite safety shelf life if it is produced in accordance with CGMP [Current Good Manufacturing Process] and quality standard regulations and is stored in an unopened, properly sealed container. Therefore, FDA does not require an expiration date for bottled water. However, long-term storage of bottled water may result in aesthetic defects, such as off-odor and taste. Bottlers may voluntarily put expiration dates on their labels...”
So this sounds promising! However, it’s from 2002, and while the page was last updated in March, the last few years have witnessed increasing debate about bisphenol A (BPA), the chemical in some plastics that’s been found in baby bottles, food can liners, and some plastic water bottles. If I drink 10-year-old water from an unopened jug, will I be full of BPA?
The website of the International Bottled Water Association says that:
“BPA is a chemical building block used primarily to make polycarbonate plastic and epoxy resins... Many bottled water companies use polycarbonate plastic for their 3- and 5-gallon water cooler bottles. It is not, however, used in any retail-sized PET bottled water containers... As noted by Health Canada, an adult would have to drink approximately 1,000 liters (or 264 gallons) of water from polycarbonate water cooler bottles every day to approach the science-based safe intake limit for BPA recently established in Canada.”
So it probably isn’t in your water jug, and even if it is, it probably isn’t bad for you according to this website. Now admittedly, this is the bottled water industry speaking here. So let’s check back with the FDA, in an article about BPA checked 7/1/13 that was last updated 5/24/13:
“The Food and Drug Administration’s assessment is that the scientific evidence at this time does not suggest that the very low levels of human exposure to BPA through the diet are unsafe.
The agency has performed extensive research on BPA, has reviewed hundreds of other studies, and is continuing to address questions and potential concerns raised by certain studies.
FDA scientists have also recently determined that exposure to BPA through foods for infants is much less than had been previously believed and that the trace amounts of the chemical that enter the body, whether it’s an adult or a child, are rapidly metabolized and eliminated.
Research has shown that people are exposed to BPA because small amounts can migrate into the food and beverages from their containers. Reports from some animal studies have raised potential concerns that BPA exposure may cause multiple health problems, including reproductive disorders, diabetes and cardiovascular disease.
There have also been studies that contend that BPA is a hazard to people too. But FDA—as well as the European Food Safety Agency (EFSA)—has carefully assessed these studies and finds no convincing evidence to support that belief.”
The FDA’s assessment will satisfy some people, but not everyone. Therefore, the next quote from their website is probably the most important:
“Plastic containers have recycle codes on the bottom. Some, but not all, plastics that are marked with recycle codes 3 or 7 may be made with BPA.”
Aha. So I went into my closet in which I had installed extra shelves on the back wall to hold 12 gallons of water (we just did not have any room for gallons 13 and 14!) and took a look at one of the jugs, with 2011 expiration dates. The recycle symbol shows a 2. So now I have a few more reasons to feel ok about storing my emergency water for a long time, and not minding if it tastes a bit off if I ultimately have to use it. If you are concerned about BPA, you can at least make sure you get water jugs that don’t have the 3 or 7 recycle symbol.
Remember also that if worse comes to worst, you can drink the water in your water heater assuming it is undamaged, and yes, the UPPER tank of your toilet has water that has never touched anything undesirable, as long as it is clear and colorless and doesn’t have added toilet cleaners. The running water from the tap might be suspect if the water pipes are damaged, so if that is all you have, the Centers for Disease Control and Prevention (CDC) says to pass it through a coffee filter or cloth if it is cloudy, and boil it for 1 minute (3 minutes over 6500 ft elevation) before drinking whether it’s cloudy or clear. If boiling isn’t an option, water purification tablets or a tiny bit of bleach can sterilize it; to 1 gallon water, add 1/8 teaspoon unscented bleach (8 drops, 0.75 milliliters) if water is clear or twice that amount if water is cloudy; mix and wait for 30 minutes.
(Did you know that San Francisco has emergency drinking water hydrants all over the city? Here's a map. I’m not sure about other cities.)
Hmm, I see that the same CDC website also says “observe the expiration date for store-bought water” and so does the Red Cross. Argh....well, it sounds like the FDA has been studying the issue pretty thoroughly and they are the ones who are charged with regulating bottled water.
Note though that if you take your own water from the tap or another source and store it in your own bottle, all bets are off. There’s no guarantee that you will have safe water to drink after 6 months; it depends on the condition of the water and the composition of the container or liner that you use. Also, everything I’ve said is based on US standards and I can’t vouch for its accuracy if applied to other countries. Nonetheless, if you are buying bottled water in the US or of comparable quality standards, hopefully this information has quenched your thirst for knowledge.