Sterols in marine sediment and fauna at Davis station 2009/10

Faecal sterols (primarily coprostanol) in sediments have been used for assessment of human sewage contamination in this environment, but in situ production and indigenous faunal inputs can confound such determinations. Using GC-MS profiles of both C27 and C29 sterols, potential sources of faecal sterols were examined in near shore marine sediments, encompassing sites proximal and distal to the wastewater outfall at Davis Station, Antarctica.

Faeces from indigenous seals and penguins were also examined. Several indigenous species faeces contained significant quantities of coprostanol but not 24-ethylcoprostanol, which is present in human faeces. In situ coprostanol and 24-ethylcoprostanol production was identified by co-production of their respective epi-isomers at sites remote from the wastewater source and in high total organic matter sediments.