Fecal sterols as sewage contamination indicators in Brazilian mangroves

Araújo, Michelle P.; Hamacher, Claudia; Farias, Cassia O.; Soares, Mário Luiz Gomes

doi:10.1016/j.marpolbul.2021.112149

Cited by 9 publications

(1 citation statement)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…coli] and [stanol] WS can be considered high. In the environment, the highest stanol compound concentrations are often found at sampling sites located near domestic outfalls, and concentrations tend to decrease with distance from the sources, involving mixing and dilution processes. ,,− Hence, lower concentrations of stanol compounds found in, e.g., the Mekong Delta , are consistent with higher concentrations at the outlet of a village located within a headwater catchment such as the Laksip village. A common feature in rural areas of developing countries is that although some families have individual treatment systems (septic tanks), surface runoff water and most wastewater are not stored or treated before entering the river network.…”

Section: Results and Discussionmentioning

confidence: 98%

Village Settlements in Mountainous Tropical Areas, Hotspots of Fecal Contamination as Evidenced by Escherichia coli and Stanol Concentrations in Stormwater Pulses

Boithias,

Jardé,

Latsachack

et al. 2024

Environ. Sci. Technol.

View full text Add to dashboard Cite

Fecal bacteria in surface water may indicate threats to human health. Our hypothesis is that village settlements in tropical rural areas are major hotspots of fecal contamination because of the number of domestic animals usually roaming in the alleys and the lack of fecal matter treatment before entering the river network. By jointly monitoring the dynamics of Escherichia coli and of seven stanol compounds during four flood events (July–August 2016) at the outlet of a ditch draining sewage and surface runoff out of a village of Northern Lao PDR, our objectives were (1) to assess the range of E. coli concentration in the surface runoff washing off from a village settlement and (2) to identify the major contributory sources of fecal contamination using stanol compounds during flood events. E. coli pulses ranged from 4.7 × 104 to 3.2 × 106 most probable number (MPN) 100 mL–1, with particle-attached E. coli ranging from 83 to 100%. Major contributory feces sources were chickens and humans (about 66 and 29%, respectively), with the highest percentage switching from the human pole to the chicken pole during flood events. Concentrations indicate a severe fecal contamination of surface water during flood events and suggest that villages may be considered as major hotspots of fecal contamination pulses into the river network and thus as point sources in hydrological models.

show abstract