Car tires sitting in water will it cause PSI problem?

About a month and a half ago we had a hurricane hit the area I live in. We had some bad flooding in my apartment complex and since my car was parked outside it stood in the water about a good 2-3 days. The water was about half my tire in height. Since then I’ve noticed that the air in all four of my tires constantly goes down. I refill them to the PSI listed and then a week or so goes by and they start going down again. Today one of my back tires went from being around the required PSI to 17 psi overnight. I can check the levels because my car let’s me know when the psi is low. My question is could my tires have been damaged by them sitting in the water for those 2-3 days or could it be some other reason? Thank you