Our diets can have a lot to do with this problem. Sometimes eating or not eating certain things can enhance B.O. problems. Maybe if you befriend the offender you can find out if it's hygiene, nutritional, genetic or homelessness. Knowing these things can help you solve the problem.
If the offender has made the 30 days and you will be working near them for quite some time, I'd definitely try to get to the "bottom", (no pun intended), of this situation, before it "brews" into a bigger "mess"

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