Testing for tainting with pharmaceuticals is no doubt going to find it mostly in weight loss and sex pills. Heavy metals you'll find in the herbs. Proteins woul

Testing for tainting with pharmaceuticals is no doubt going to find it mostly in weight loss and sex pills. Heavy metals you'll find in the herbs. Proteins would probably be more contaminated with animal/food related issues like in canning. The general problem is that whatever you look at you are likely to find a type of contamination that isn't being checked for with the same level of oversight as the food industry or the pharmaceutical industry.