Steroid markers to assess sewage and other sources of organic contaminants in surface sediments of Cienfuegos Bay, Cuba

Microbial water quality and sedimentary faecal sterols as markers of sewage contamination in Kuwait

“…It is also worthy to note that Saeed et al (2012), reported the highest values of coprostanol (41,228 ng g À1 dw) at Al-Fintas (S09 in this current study), which is also where a review of the EPA microbial water quality data recorded extremely high episodic pulses of microbial contamination. In comparison to studies conducted elsewhere the levels of coprostanol measured were similar to surface sediments from Venice Lagoon, Italy (40-4410 ng g À1 ; Fattore et al, 1997); Sochi, Black Sea Russia (54-5400 ng g À1 ; Readman et al, 2005), the Danube coastline, Black Sea Ukraine (170-2600 ng g À1 ; Readman et al, 2005), Babitonga Bay, Brazil (30-6080 ng g À1 ; Martins et al, 2014) and Cienfuegos Bay, Cuba (10-5400 ng g À1 ; Tolosa et al, 2014).…”

“…Lyons et al / Marine Pollution Bulletin xxx (2015) xxx-xxx 100 ng g À1 dw are indicative of uncontaminated environments, values greater than 100 ng g À1 dw indicate sewage contamination, while those in excess of 500 ng g À1 dw signify gross sewage pollution (Grimalt et al, 1990;González-Oreja and Saiz-Salinas, 1998;Tolosa et al, 2014). Of the 29 sites sampled 3 exceeded the 500 ng g À1 dw coprostanol threshold, indicating significant sewage pollution at these locations (Fig.…”

“…One of these chemical markers is coprostanol (5b-cholestan-3b-ol), which comprises 40-60% of the total sterols in human faecal waste, and has been used widely around the globe as a marker of sewage contaminated (Al-Omran, 1998;Readman et al, 2005;Reeves and Patton, 2005;Adnan et al, 2012;de Abreu-Mota et al, 2014). Coprostanol like many other faecal sterols is hydrophobic, readily associating with particulate matter in sewage effluent and consequently is incorporated into bottom sediments (Tolosa et al, 2014). Studies have demonstrated that coprostanol concentrations correlate well with coliform bacteria, especially in sewage contaminated environments (Isobe et al, 2002).…”

“…Under anoxic conditions coprostanol is relatively persistent and any decline will invariably be associated with sediment transport. In tropical waters coprostanol, along with other selected sterols, are considered to be a more robust and reliable marker of sewage pollution than faecal coliform enumeration (Carreira et al, 2004;Adnan et al, 2012;Tolosa et al, 2014). To gain a full understanding of sewage input and source, the analysis of coprostanol is also assessed in relation to other sterols.…”

“…To gain a full understanding of sewage input and source, the analysis of coprostanol is also assessed in relation to other sterols. For example, epicoprostanol, an isomer of coprostanol, can be used as a marker to indicate the level of treatment or age of the faecal matter (Readman et al, 2005;Martins et al, 2014;Tolosa et al, 2014). This compound is a by-product of sewage treatment systems and will only occur in low concentrations if the sewage is not treated or only partially treated, increasing in anoxic environments such as sewage sludge .…”