Hi, not all of Clarkson's Iodine is from Ricca. I stand corrected perhaps, but I don't think Ricca says poison on it. Aside from that, I agree with the earlier reply that the poison warning is to protect the manufacturer against use for which the product has not been sold and for purposes of this forum I would not be alarmed.
Finally, I do sell Ricca which is rated as Equivalent to USP and my house brand
which is USP without any qualifications.
Jeff@Crows