Yes, it is fine. Look on the bottle and try to find the code for the type of plastic is is (probably on bottom). If it says PET 1 or PETE 1 you are good to go. I have several 6 gallon from vintage shop and better bottle and that is the code on them as well. I also just brought home a new 5 gallon water bottle i purchased from walmart that was only 5 bucks. The code on that is also PETE 1. I really like the plastic carboys as they are much lighter than glass and easier to move around especially when full. When they are empty they are so light that you can juggle them...lol.