Faecal sterols as indicators of sewage contamination in estuarine sediments of the Tay Estuary, Scotland: an extended baseline survey

Abstract

Abstract. Sterol ratios are used to identify sources, occurrence and partitioning of faecal matter in sediments of the Tay Estuary, Scotland. The 5β/(5α+5β) ratio is used to discriminate between sewage and biogenic sterol sources by comparing the concentrations of coprostanols to cholesterol plus coprostanols. This index shows unambiguous sewage pollution in the Invergowrie Bay area (values >0.7). The coprostanol/epicoprostanol index is used to differentiate between human and non-human faecal inputs. Ratios confirmed the primary source as human-derived faecal material. The coprostanol/cholesterol ratio was calculated in order to elucidate the contribution of different biogenic sources to the sedimentary sterol budget. Ratios of >1 clearly indicate faecal sterol sources. Invergowrie Bay displayed no sterol signature other than sewage. A biogenic source of cholesterol influenced total sterol concentrations upstream of the City of Dundee. Attention is directed to the potential role of density fronts in compartmentalization of faecal material in bottom sediments.

Identification and significance of sterols in MSW landfill leachate

“…For example, linear alkylbenzenes (LABs) have been used as molecular tracers of domestic wastes [1,2]; stanol and stenol for faecal pollution [3,4]; and polycyclic aromatic hydrocarbons (PAHs) for oil fingerprinting [5,6]. For example, in the past decade, coprostanol has been recognized as a reliable indicator of faecal pollution of water [7][8][9]. Coprostanol is produced by the microbial reduction of cholesterol in the digestive systems of higher animals [10,11].…”

“…Although coprostanol as a faecal indicator in aquatic environment has been widely used for a long history [7][8][9], its quantitative aspects are still being refined. Several researchers have demonstrated a positive correlation between coprostanol concentrations, particle size, and fraction organic carbon [20,21].…”

Distribution and sources of phytosterols in coastal and river sediments of south central Chile

“…A possible explanation for the difference in phytosterol concentration found off south-central Chile in comparison with the sediments off Peru is sediment granulometry, because in the latter case there were mostly muddy sediments, whereas off south-central Chile there was fine sand (Volkman et al, 1987). It is known that finer sediments lead to greater retention of sterols (Reeves & Patton, 2005).…”

Use of Enterococcus, BST and Sterols for Poultry Pollution Source Tracking in Surface and Groundwater

“…Sterols indicative of fecal source pollution (cholesterol, coprostanol epicoprostanol desmosterol and dihydrocholesterol) were detected in all surface water samples; phytosterols (campesterol, stigmasterol and b-sitosterol), an indication of herbivores pollution sources, were detected (Leming et al, 1996;Reeves & Patton, 2005). The presence of individual sterols is generally not sufficient for tracking of fecal pollution in the environment although, for example, coprostanol is considered a marker for sewage contamination (Leeming et al, 1996, Shah et al, 2007.…”