Good question! Our carbonating bottles have an expiration date when used for carbonation. Our bottles are made to withstand extreme pressure changes, and since plastic degrades over time, the bottles sadly can't be used forever for carbonation.
Make sure to check the expiration date and care information on the bottle before using and purchase new bottles as soon as the original bottles expire.
Old bottles can still be used to store sill water, but if you want to dispose of the bottles, all parts of the carbonating bottles except for the seal inside the cap are recyclable. Please check with your local recycling authority for more information on sustainable disposal options.