A recent University of Alberta research looked into body odor and stinky clothes to find that cotton shirts did not stink as much as polyester shirts, before and after they were washed.
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The study revealed the presence of 1,000 to 2,000 molecules on every dirty shirt sample. After washing, the number of molecules on the cotton shirts reduced markedly than the molecules on the polyester shirts.
It is yet unclear which molecules contribute to the smell.
"Human sweat, in and of itself, doesn't smell. It’s the microbial action on the sweat, as the microflora on our skin and on our toes (interacting), that’s what generates the smelling compounds and molecules," researchers said.
Source-Medindia