Getting som blood tests done next week for first time in over 5 years, noticed on the test papers it says Purple Top EDTA (FBC) and Yellow top SST gel (B12, fol, FEr, TFTF, Bone, UE, LFT)> The EDTA and the SST gel I’m guessing is the contents of the container bottle.. does any of that substance get into your blood system during the blood taking or is purely just collection?