Okay, when I first starting to quilt 6 years ago, I was at a garage sale and the lady had 3 boxes of large wooden spools of mercerized cotton thread. There was 20 spools in each box and all colors. She told me she had stored them in here basement. No odors in them. They were $5.00 a box so I bought them. Well when I got them home, I tried to see how easily the thread broke. Immediately!!!!! Well, I sat back and thought a moment and then I took one spool and started unwinding the thread, snapped it, broke, kept going and all of the sudden I reached a point where the thread did NOT break. So, I sat watching TV in the evening with the hubby for the next couple of weeks and I think about a third of each spool had deteriorated but then I would hit the spot where it was strong and I couldn't break it. I have enough colors and thread to last quite a while. I store it in plastic boxes and it is protected from moisture! Just letting you know my experience.