Cotton is probably bad for biking anyway as it’s a sponge so your sweat will just leave you with a drenched shirt. But I am trying to avoid plastic clothes bec

Cotton is probably bad for biking anyway as it’s a sponge so your sweat will just leave you with a drenched shirt. But I am trying to avoid plastic clothes because of their environmental impact, and possible leachate ending up in (or through) my skin. Wool, and cotton/wool blends work for me even in the summer. Amazingly a return to my childhood in this regard! But they are a little more work to look after than the plastics.