A short answer is, yes, juice bags are safe. Let us see why.
A juice pouch is a small plastic bag that contains juice, and occasionally has a spout glued to it. The juice contained in such a bag is usually less than that in a plastic bottle and other packaging methods. This small amount of juice makes them single-serving packages. In other words, these bags usually carry only so much juice that can be consumed in a single drink. This reduces the risk of bacteria sneaking into the packaging, as the packet remains open only for a few minutes – while you are drinking from it. When the juice is finished, the pouch goes into the trash can. This is safer than larger plastic bottles where the likelihood of bacteria getting into your liquid packaging increases every time you open it.
Juice bags are safer than other kinds of food and beverage packaging for a second reason too. It is easier to detect a leak in a pouch of juice than in a plastic bottle, especially when it is near the opening. Detection is easier in juice pouches because the liquid oozes out, which may not happen in a plastic juice bottle with a puncture near the top.