Over time, reusable plastic water bottles occasionally develop unpleasant odours and/or tastes. This typically occurs when bottles are stored incorrectly or cleaned infrequently.
Most rigid water bottles are made out of either polyethylene plastic (which tends to be cloudy in appearance) polypropylene (which comes in medium to dark colours) or co-polyester (which can be clear, frosted or coloured). Most hydration system reservoirs have polyethylene linings, which retain tastes and odours more easily than polycarbonate. But all plastic bottles can develop unwanted tastes or odours if cared for incorrectly.
The best way to maintain any plastic water bottle or bladder bag is to rinse it out after each use and to let it air dry completely. Most odour and taste problems occur when bottles are stored in wet areas or kept sealed for long periods of time with liquid inside. Polyethylene bottles can also develop unpleasant tastes/odours when they’re used to store a variety of acidic juices.
If your water bottle develops a bad taste or odour, try the following procedure:
Tip: Some tastes and odours can be removed from plastic water bottles simply by rinsing them with anti-bacterial mouthwash.