In this case you can consider 16m as theoretical. If capsaicin is not dissolved in something. It won't reach your pain receptor and simply do nothing. If you know where the scoville scale comes from, 16m unit is real, it really needs to be diluted 16 million times to be undetectable by normal humans. But if it can't reach your pain receptors, it will actually feel less hot than properly dissolved capsaicin.