Psittacofulvins in blue1 or blue2 feathers?

Blue Agapornis fischeri and Agapornis personatus are considered not producing any psittacofulvins (psittacines) in the feathers. However, we could not ignore the fact that there are breeders who argue that their – pure bred – blue2 birds sometimes show traces of psittacofulvins in their feathers (to be clear, blue2 not in combination with *sapphire*).
Others are 100% sure and state that even in budgerigars [Melopsittacus undulatus] and ring-necked parakeets [Psittacula krameri], blue (possible blue2 ???) birds always contain psittacofulvins remains in their feathers.  If we consider the possible genetic causes behind this mutation, then we can not completely exclude this possibility.
So, we believed it was time to try to find a clear answer and not to continue to rely on assumptions. There fore, we have collected feathers from (100% pure bred) blue2 Agapornis fischeri and Agapornis personatus. We have scan them with the Raman technology and found is NO evident or any traces of psittacofulvins in the feathers of blue1 or blue2 birds.