Healthspan, Simply supplements, Natures Best etc. etc. all the known producers of supplements, manufacture them under stringent Government controls / conditions. Some........Healthspan for instance, operate out of the Chanel Islands; for business or Tax reasons, but still have to adhere to UK government manufacturing controls. The controls aren't just about the supplement itself, that is contained in each Tablet / Capsule; it's about the Binding agent in the Tablet / Capsule, that allows it to keep it's form. It's the same as cutting Heroine down from its pure form, to whatever purity is required, normally using sugar. Unscrupulous dealers will use Talc ( which is carcinogenic ) or other even worse additives. Supplements are totally different of course and I only use the analogy as an example. They do still however have to have additives, so that the Tablet / Capsule can have the varieties of strengths that are offered. The source of the Supplements and the additives contained in the Tablets / Capsules, are what is strictly controlled; so from a disreputable source, you would not be able to verify any of those facts. Why eBay doesn't control who sells these supplements, is beyond me; they won't allow Guns or Knives to be sold, but apparently don't guard against somebody being poisoned.