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Math of plastic water bottles

By Murray Bourne, 22 Apr 2009

water bottles

Today is Earth Day. I have become somewhat cynical of these one-off "environmental awareness" events, since they cause a flurry of activity for a short time, then fade away. But at least it's a start and if we manage to convince a few people to look after the planet a bit better, I guess it's worth it.

The Plastic Water Bottle Scourge

In many countries, there is no tap water at all, so clean bottled water is a valuable resource. In certain other countries, the tap water is so polluted that many people will use bottled water if they can afford it (I always do so when I am traveling around Asia).

But in the countries where tap water is abundant and (reasonably) clean, why is there such a love affair with plastic bottles?

water bottle pollution

In the US, sales of bottled water have skyrocketed, to around 30 billion plastic bottles sold during 2005.

The environmental cost of this is huge:

  • The plastic is a petroleum product and its manufacture pollutes air and water
  • Transport of the bottles uses up more gasoline
  • The water may have been pumped from river systems that are already fragile, disturbing wildlife and livelihoods downstream
  • A large proportion of plastic bottles are not recycled (or cannot be recycled) so they go into landfill, or end up in waterways and the oceans, ready to be consumed by wildlife
  • Re-using plastic water bottles can mean ingesting toxins - they are normally intended to be one-use affairs (of course, to increase sales).

The dollar cost: Tap water typically costs around 1/20 of 1 cent per litre, but consumers spend between 240 and 10,000 times as much on bottled water. (Bottled water is $500–$1,000 per cubic meter, compared with 50Β’ per cubic meter for tap water in California. One cubic meter of water is 1000 L, so 1 liter costs 0.05Β’. That's not 5Β’, it's 0.05 of 1 cent.)

This is yet another example of consumerism gone mad. It's ridiculously expensive, it's polluting, it's toxic and in many cases, it's unnecessary.

When you need to carry water with you, do yourself, and the Earth, a favor — use a re-usable bottle and be happy with tap water (filter it if you must).

[Image sources: Kiki and Quinn.anya.]

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