When purchasing Organic Germanium, the primary focus must be on purity and chemical structure. You should demand a Purity Level of ≥99.9%. It is critical to distinguish between Organic Germanium (Ge-132) and inorganic germanium dioxide (GeO2), as the latter is toxic. Ensure the CAS Number is 12758-40-6. Additionally, check the Heavy Metal Content, specifically ensuring that Lead (Pb), Arsenic (As), and Cadmium (Cd) are <1ppm, and the product is 100% free of Inorganic Germanium through rigorous lab testing.