Determination of faecal pollutants in Torrens and Patawalonga catchment waters in South Australia using faecal sterols

This research investigated faecal pollution by sterol profiling in two Adelaide metropolitan catchments in winter 2000 and summer 2001. Water was sampled from five sites on the River Torrens and two sites on Patawalonga river catchment. The steroids detected were coprostanol, epicoprostanol, cholesterol, cholestanol, stigmasterol, betasitosterol, and stigmastanol. The concentrations range from 5 ng/L (of coprostanol) to 34 microg/L (of stigmasterol), with cholesterol detected more frequently at relatively high concentrations (approximately 2 microg/L). Sterol profiling suggested two sites on two occasions may have been impacted by human faecal contamination. Other steroid profiles suggested that sources of pollution consistently included dogs and birds. The steroid concentrations in the Torrens catchment were higher in winter, however, this was not observed in the Patawalonga catchment.