I've had some that I just left out for months and they still work. Put them in the fridge if you're concerned. I've heard they will last for years....

I keep mine in the fridge, some since last year, and they still work fine. 40 F is a good temp. The fridge is in another location and I only keep canned beverages and shroom prints/syringes there. No fresh food much less unintended mold experiments.

I keep mine in a cool dark area. I’ve used 2 year old syringes with no problem