Several people have suggested that the high lead (17 ppm) in this Bio-Syn UOA (compared to a mere 3 ppm of lead in my Pennzoil Platinum UOA, with 2 ppm being the universal average) may be a result of Bio-Syn cleaning off Anti-Wear additives from the engine's surfaces that have accumulated over the 3.5 years the car has been alive. Apparently, some oils have lead in them as an Anti-Wear additive, but these lead-containing oils seem to be rare.
In my signature, you'll see that the previous oils I've used have been Pennzoil Platinum, Mobil 1 5w-30, and Valvoline dino (the Valvoline was a dealer bulk supply before I started doing my own oil changes. I think I only used the Valvoline bulk once--no more than twice).
I've been looking at many Virgin Oil Analyses on this site, and I don't understand from which of my previous oils the lead could have come from. PP, M1 5w-30, Valvoline dino, and RLI Bio-Syn 0w-30 don't appear to use lead as an anti-wear additive.
I can only conclude, then, that the high lead came from the bearings, possibly as a result of the high 8.5 TAN to 2.0 TBN ratio. Iron, by the way, was also higher than I would have expected, though not extreme like the lead.
Others have noted that ester oils like BioSyn start off with a high TAN, and that's true, but the Virgin Oil Analyses I've seen usually show a virgin TAN for BioSyn between roughly 2 and 3. My UOA's TAN was 8.5.
Can anyone point out a UOA of Bio-Syn on this site that had a TAN over 6?