Determining the microbial and chemical contamination in Ecuador’s main rivers

Abstract

One major health issue is the microbial and chemical contamination of natural freshwater, particularly in Latin American countries, such as Ecuador, where it is still lacking wastewater treatment plants. This study analyzed the water quality in twelve rivers of Ecuador (Coastal, Andean, and Amazonian regions). All rivers showed levels of E. coli and total coliforms above the maximum limit according to International and Ecuadorian legislations. The most polluted rivers were Zamora, Esmeraldas and Machángara. Also, E. coli pathotypes were found in six rivers. Several physicochemical and metal parameters were detected in high levels, such as CODTOTAL (in eight rivers), TSS (in six rivers), TS (in two rivers), Al (in nine rivers), Zn (in eight rivers), Pb (in three rivers), Cu (in three rivers), Fe (in two rivers), and Mn (in Machángara River). Our results agree with other studies in Latin America (such as Colombia, Brazil, and Peru) reporting similar contamination in water resources used for agriculture, livestock, and human consumption. Overall, Guayas, Guayllabamba, and Machángara Rivers showed the highest levels of physicochemical parameters (such as CODTOTAL and TSS) and metal concentrations (such as copper, zinc, aluminum, iron, and manganese). Further studies should evaluate contamination sources and public health impact.

Comments on the reduction in emerging contaminants in water samples from the Esmeraldas coast (Ecuador)

“…The relationship of Enterococcus faecium with faecal contamination can support the thesis that Ecuador rivers may be possible sources of this Gram-positive cocci, as recent research has reported that coliforms are above the maximal threshold established by USA, European and Brazilian guidelines ( Vinueza et al, 2021 ). Moreover, it is possible that other bacterial species, such as Rhodococcus ruber , which easily grows on plastic elastomers (usually polluting seawater and shores), participated in degrading pharmaceuticals available as ECs, for example diclofenac ( Mor and Sivan, 2008 ; Ivshina et al, 2019 ).…”

Dairy Farmers’ Willingness to Adopt Cleaner Production Practices for Water Conservation: A Discrete Choice Experiment in Mejia, Ecuador

“…The canton of Mejia is our case study because, in addition to being the leading Ecuadorian milk-producing region, it suffers from inefficient water management (Cachipuendo et al, 2017;GAD Provincia de Pichincha, 2015;Nieto et al, 2018), water pollution by solid and animal waste (Andrango and Sandoval, 2021;Bonifaz, 2018;Vinueza et al, 2021), and conflicts among water users (GAD Provincia de Pichincha, 2015). For instance, the primary irrigation systems in Pichincha are overhead sprinkler systems or flood irrigation techniques, resulting in only 60% of the water being purposively used (GAD Provincia de Pichincha, 2015).…”

History, Current Situation and Challenges of Gold Mining in Ecuador’s Litoral Region

“…As a result, chemical pollution is produced on the banks of the water bodies that flow through the mining areas by processes that release substances such as mercury, cyanide, nitric acid, zinc, lead, arsenic, cadmium and manganese [11][12][13][14]. They can also affect aquatic diversity, terrestrial ecosystems and even people [15][16][17][18].…”