firstly, there was barely any odour. Some others have said that it would be so toxic smelling but honestly there was nothing noticeable at all.   I have to admit that I was skeptical at first given how compressed this topper was when it arrived. I followed the instructions to let it rise for 48 hours+ and it did completely!! every single crease and compressed spot was gone.  I put a cozy mattress cover on top and beautiful new sheets and WOW this is the most comfortable bed. I did want to mention that this box said 3inch topper not wayfair basics as ordered, but I didn't care.