Should we keep re-using our water bottles?

Is it really dangerous to rinse and refill disposable plastic bottles?

Bacteria can grow on the surface of plastics, so washing your bottles between use is a must; a bottle brush and hot soapy water can help you get into all of the nooks and crannies. However, disposable bottles are usually made from thin polyethylene terephthalate (PET), which will start to crease and crack with time, providing even more places for bacteria to hide and grow.

You might sometimes hear that components from plastics will leach into your drinks over time too. In the UK, the Food Standards Agency and the European Commission regulate the materials that come into contact with our food and drink. They set rules about the types of plastics that can and cannot be used and the acceptable limits for the amount of plastic that can safely enter food.

Bisphenol A (BPA) is the chemical that’s most often mentioned, but so far the evidence that it causes harm to people isn’t conclusive. Plus, it’s used in the manufacture of rigid polycarbonate bottles, not disposable PET ones. If you’re worried, your best bet is to get hold of a reusable aluminium, steel or glass bottle and avoid the plastic conundrum altogether.


Cover image by priyanka98742

For more amazing science and technology news, check out the latest issue of How It Works. Pick up your copy from from all good retailers or from our website now. If you have a tablet or smartphone, you can also download the digital version onto your iOS or Android device. To make sure you never miss an issue of How It Works magazine, subscribe today!