What is a safe lubricant for around a baby? (Squeaky crib)?

I just bought a crib, and it has not been used in a while, it is very squeaky when you put the side rails up and down, i want to lube it up, but didnt think i should use WD-40, as it will be near the baby. Is there something else that will work to stop the squeak that is safe to use around babies? or is WD-40 safe? (Baby will not be able to chew in the part that needs lubed, and baby will not be here for another 2 months, so fumes shouldn't matter, but was wanting to be safe rather than sorry! ((Thank you mom)))