Urobilin hydrochloride is the metabolite of Hemoglobin (HY-P2995), that can be excreted through urine and feces in many mammals. Urobilin hydrochloride can be used as an indicator of human waste pollution[1].
References
[1] Jones-Lepp TL. Chemical markers of human waste contamination: analysis of urobilin and pharmaceuticals in source waters. J Environ Monit. 2006 Apr;8(4):472-8. DOI:10.1039/b512858g
