While traditional “smoking” via a joint is still the preferred by most, cannabis concentrates, or “BHO wax” have gained traction. Here's why...
wayofleaf.com
Ahhhh, thank you for posting a credible source! I prefer facts over opinions. Also, something not covered in that article is the fact that you will still have waxes and lipids in your rosin as well. For example, if your hash tests at 65% total cannabinoids mg/g, what is the other 35% of the mass? The answer, waxes, lipids, esters, plant material, etc...
As a side note, no cannabis professional I’m aware of will ever claim to be able to purge 100% of any solvents out. However, the FDA says over 4000ppm could pose a health hazard because it displaces oxygen. In MA, the maximum allowable limit is 12ppm in any extract.