Q. Can one use olive oil that was left uncovered overnight for lighting the Chanuka menorah?
A. Kaf Hachaim (673: 11) quoting Ben Ish Chai, rules that one should not use for lighting the Chanuka Menorah olive oil that was left under one’s bed overnight and someone slept over it, as it acquires a spirit of impurity (ruach ro’oh), and one should avoid consuming it. Therefore, following the principle, that one should only use for the Menorah with oil that is fit for personal consumption. it should not be used.
However, there are Poskim that permit (See Piskei Teshuvos 673; 4: n. 31).
Horav Shlomo Miller’s Shlit’a opinion is that after the fact, one can use it.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a