Coprostanol (5β-cholestan-3β-ol) in lagoonal sediments and mussels of Venice, Italy

Coprostanol, a fecal sterol indicative of mammalian waste, was analysed in sediments and mussels collected from 25 stations in the canals and lagoon of Venice, Italy, to investigate dispersal and accumulation of untreated sewage. Concentrations of sedimentary coprostanol ranged from 0.2 μg g−1 in a reference station in the northern Adriatic Sea to 41 μg g−1 in an interior canal of Venice. These values made up 4% to 44% of the total sterols, and indicated which areas of the lagoon had the greatest contribution from sewage discharge. Coprostanol concentrations found in mussels were lower and less variable than in sediments, indicating that sedimentary coprostanol concentrations are a better indicator of sewage discharge in the lagoon. Areas with high sedimentary coprostanol concentrations either lacked mussels entirely or contained mussels showing severe environmental stress. Data suggest that sedimentary coprostanol concentrations appear to be a useful indicator of potential ecological problems in the lagoon and canals of Venice due to the direct input of untreated waste.