I started out years agowearing wool.  It was, and still is, pretty good, but over time I have switched to synthetics - more durable,as warmer if not warmer, easier to care for.  As for the enironment, I still have and use the Patagonia fleece I purchased in 1981.  I would have worn out several wool garments in that time.

 

Go wool if you like, but I wouldn't lose any sleep over the issue...

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