I would defiantly clean it. Are you sure nothing was sprayed on it or near it? I would be leary of using it after it sat out side . Once you have determined it to be safe . I would also hit it with a power washer with just plain water and give it a good spray down if there is dirt or any thing on it
. I would also place it in water and allow it to leach out any thing bad you can use just old used salt water (if you have it ) or RO
water changing it out every other day .. Then place it into your tank add a bit of live rock from a couple places if possible and go from there .