So bisphenol-a and a lot of these plastic chemicals, the primary root of excretion is through urine ... Sauna, you're excreting mostly is through sweat. And there are a lot of toxins that we're exposed to that we do excrete through sweat. A lot of those are heavy metals. So for example, cadmium and aluminum ... They're more readily excreted through sweat than through urine. And so when you get in the sauna, you can excrete a little bit of BPA. It does come out through sweat as well. However, the majority of chemicals that are being excreted through sweat are heavy metals.