When buying pure fruit juice do we need to be concerned whether the fruit used to make it is from Israel.
If it is possible to verify where the fruits came from, you should. For example, if you are buying it from a private store that is squeezing it for you, and you can ask the store owner, that is what you should do. (As a side point, when asking him don’t make it obvious what he is supposed to answer, rather tell him, “I hope these come from Israel”. This way, if he says that he doesn’t know or that they don’t, you know that he is saying the truth.) If you can’t verify the origin of the fruits, you may assume that they don’t come from Israel, as most fruits in the world do not originate from E. Yisroel.
R’ Y. Cahen shlit”a