Contaminants which cause all manner of adverse reactions including but not limited to infections. The whole issue of filtering semi-finished oils from bulk vendors has been beat to death around here.Do you mean contaminants that can cause infections? I have had good luck with domestic sources even on SST and haven't had too many issues. But prices keep getting more expensive on everything and most of them are using chinese sources anyways. I mean I seen some of the setups from sources on SST and they were a joke. I imagine there are more labs in china because they produce pharmaceuticals worldwide. My logic tells me if some backyard bandits on SST can produce a decent product, there is a good chance that established chinese companies can produce good products
Better safe than sorry but assume whatever risk level makes sense to you.
