system
Given the following post, respond as if you're commenting on Reddit:
human
what causes green / yellow color in the armpits of shirts? 

I have had this problem with my shirts for as long as i can remember. It is not visible on my colored shirts but is very noticeable on my white shirts. I have been told that it is the type of deoderant that is used but im not too sure on that because i have used a couple different ones and the same thing still happens. It does not wash out of my shirts for some reason either. The shirts would be washed and you would not be able to see the yellow color in the armpit but if wet with water in that area you could see it. What causes this? How could i remove it? prevent it?
gpt
It's the reaction of your aluminum based antiperspirant with laundry detergent. You can minimize it by letting your antiperspirant dry before putting on your shirt or by using a deodorant without an aluminum based antiperspirant.