My dreads are currently 5 years old and are completely natural. No hooking, waxing, ect. Just purely let them do their own thing. Regardless of this approach, I seem to have some form of residue in my dreadlocks that is blue-ish, with no smell and I recall it being a little sticky (if I rubbed it) if I managed to get some out of my dreads. I am of the impression that this could most likely be the residue of conditioners featuring emulsifying wax and in turn I no longer use any conditioners for some time now. I recall noticing discussions about this issue and I remember that certain products on the dreadlockssite shop can help remove such waxes from your hair.
I'll add a picture or two when I have the time.
Thank you for your time.