So how do I know if a supplier is providing a safe product?
Perhaps reading this ...
EU MRL Testing and Yunnan Sourcing Brand Pu-erh Teas
Yunnan Sourcing takes your health seriously! That’s why starting in October 2013 all of the Pu-erh teas produced under the Yunnan Sourcing Brand (云之源) were tested for pesticides (and for the pesticides we tested for), none of them exceed the EU's Maximum Residue Limit. Our Yunnan Sourcing Brand...
yunnansourcing.com
... will convince you to order from that purveyor of fine teas. I have ordered from him often, and been happy with the service and product.
This thread reminds me, I have to get some Russian Caravan tea. I love it’s smokey flavour.
It's the Lapsang Souchong that gives the smokey flavour, so ... you can order R.C. or L.S. with confidence.