unusual smell

I am in a small campground at Zolfo Springs, Fl. near the big Thousand Trails campground and will be there in seven days. Yes, I did smell the water heater area, refrigerator opening and could not detect any smell. The gray in the water heater is on the outside of the water heater area after the cover has been unfastened and let hang. Its like there might be a leak and ran out of the area and down the side under the panel. I was in this very campground when my neighbor had his propane tank filled. I wondered if it had anything to do with that, but the smell just did not smell like propane. I will check the batteries tomorrow, but at the moment, we are having a thunder storm go thru and its raining pretty hard. I am pretty sure that I checked the batteries before I left home the first week of Jan. I did not detect any unusual smell at that time, but I do realize that things could have changed since that time. I have not had the smell since we left this campground. My wife did say thaat on one ocassion, she smelled something bad smell of water. She has a better sense of smell than I do. Thanks for all of the help, but I will check the batteries tomorrow.

William