Bottled water in America is big business. Two years ago a quarter of the world’s bottled water was sold in the US for over $12 billion. Some might say that two years is all water can last, judging by the expiration date printed on the bottle.

Sadly, the expiration date was printed on water bottles for reasons unknown. Several sites say the date was to comply with a poorly written law in New Jersey that has since changed. That seems hard to believe and I have found no evidence that it existed. In any case (pun not intended) an expiration date certainly does not relate to safety or health of the water.

Here is the FDA statement on the subject:

Bottled water is considered to have an indefinite safety shelf life if it is produced in accordance with CGMP and quality standard regulations and is stored in an unopened, properly sealed container. Therefore, FDA does not require an expiration date for bottled water.

Those paying 1000 times the price of water from the tap perhaps would be first in line to want an indefinite life. The DHS and American Red Cross have a different recommendation:

The U.S. Department of Homeland Security and the American Red Cross both encourage the public to change their bottled water every six months.

I suspect the DHS and Red Cross really want to ensure people actually have water, or to help them remember where their water is stored. They say the six months is targeted at people who bottle their own water, to ensure that bacterium does not form. This makes bottled water seem like the less-risky option again because of the process, but the bottles themselves are another matter.

The PET (#1 or polyethylene terephthalate) used for hand-held containers and HDPE (#2 or high-density polyethylene) for big containers is said to break down from chemicals, heat and UV as well as absorb materials around it. Coca-Cola has found their Dasani bottles introduce flavor to the water over time:

Susan McDermott, says the company has done research on its own Dasani brand showing that the taste of its bottled water changes after its one-year expiration date. But, she adds: “It is probably not something the average person will notice.”

Perhaps Coca-Cola could start to market Dasani water as better with age? Instead of an expiration date, they should print the date it is bottled like a fine wine. Imagine a Dasani bottle of water from 2006 that has been stored in an oak barrel…