a lot of people might say not to do it.
i really dont see the problem and i havent really heard of there being too much of a problem before.
just realize that when u put them together in the same syringe they arent going to mix. also when u inject, the oil will inject slower than the water. so if the oil is goin in first and then it hits the water, u might want to make sure ure goin slow.
rNg