What happened to the executives of that Chinese pet food company? Some are in prison and others committed suicide.
What happened when Box Elder sent out 200mg nicotine, labeled as 58mg nicotine? Nothing at all.
What happened to the U.S. company that sent out all those salmonella ridden eggs a while back. Nothing. They're still sold under any one of a hundred different names.
What happened to all those other companies that, for years now, have been shipping all kinds of food products containing e-coli? Nothing. Some company nobody ever heard of gets some bad PR during a 24 hour news cycle and a week later no one can tell you their name.
Fact is, when an American company cuts corners and sends out contaminated products, the worse thing that happens is that they have a recall, their insurance company pays their losses and they go on with business as usual. In a severe case, they go bankrupt, lowly employees lose their jobs and the execs bail out with golden parachutes, only to pop up on the Board of Directors for a different company six months later.
Over the last 30 years or so, inspection regimens by the U.S. gov't have deteriorated to the point that they are no better than many 3rd world countries, and they are far more lax than anything Europe would tolerate.
If you're concerned about the purity of what you vape, I suggest you buy your juice from a European manufacturer that uses European nicotine and European ingredients. Otherwise, you'll be getting the same purity of nicotine and ingredients that are in your pharmaceuticals, which are Chinese in origin and are just as pure as anything cooked up in a basement in Iowa.
All the major U.S. pharmaceutical companies get their ingredients largely from China and India, and not only nicotine. The consequences for Dekang if they ship contaminated product that harms someone are FAR worse than the consequences that await any U.S. manufacturer. U.S. Standards are no more rigorous than Chinese ones. Inspections are no less lax. Corruption is no less prevalent. That's the way it is, and has been, ever since the U.S. gov't decided that regulated industries were the "clients" of the agencies in charge of regulating them. That's been going on now since the early 80's.