Content Warning: This post mentions urine storage and may be unpleasant to read. Hi everyone, This is a bit embarrassing, but I really need some advice. Due to a long illness about a year ago, I had to use 2L PET bottles to urinate in. I sealed them tightly and planned to throw them away, but couldn’t manage it. So they’ve been sitting at room temperature for about 1 year. I’m worried that opening them could release toxic gases like ammonia or hydrogen sulfide. Could opening them indoors be dangerous or make someone sick? Also, does anyone know roughly how much ammonia or hydrogen sulfide can build up in sealed urine over that time? Some of the bottles still look like the original urine color, but others have turned a much darker yellow-brown, or even almost black, which makes me even more concerned. I’m also wondering if gases might have slowly leaked out even though the caps were closed tightly. There are about 20 bottles, and this is really stressing me out. Any scientific insight or experience would be greatly appreciated. I just want to deal with this safely and move on. Thanks for reading.