Risk assessment of trace elements pollution of Manaus urban rivers

• Published in: The Science of the total environment Vol. 709; p. 134471
• Main Authors: Ferreira, Matheus da Silva, Fontes, Maurício Paulo Ferreira, Pacheco, Anderson Almeida, Lima, Hedinaldo Narciso, Santos, José Zilton Lopes
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 20.03.2020
• Subjects: Anthropogenic activity; Brazil; Cities; Contamination; Environmental Monitoring; Health risk; Metals, Heavy; Risk Assessment; Rivers - chemistry; Surface waters; Trace Elements; Water Pollutants, Chemical; Brazil; Cities; Surface waters; Environmental monitoring; Contamination; Anthropogenic activity; Health risk
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2019.134471

[Display omitted] •Trace elements inputs to Manaus rivers are allocated to the anthropogenic activities.•Waters low quality in some zones calls for decontamination management programs.•Water contamination level depends on human activities intensity.•Human exposure to trace elements contaminated water means adverse health effects. Manaus is the Capital City of Amazonas State, Brazil, in the heart of the Amazon rainforest. Its metropolitan area has a huge hydrographic basin where the disorganized urbanization has caused adverse effects in the urban rivers and creeks water quality. Thus, this study was conducted to evaluate the contents of Ba, Cr, Mn, Zn, Ni, Cu, the physicochemical parameters and their respective health risks in water samples from rivers and creeks located in urban areas with different degrees of urbanization in two different seasons. The determination of the physicochemical parameters showed the samples collected in areas with riparian vegetation presented mean values of temperature, pH, total dissolved solids and electrical conductivity lower than samples collected in urban environment. The hotspots of trace elements content were associated to the presence of industrial and domestic effluents as the main pollution source. The Water Quality Index results denoted a low water quality in four sampling sites, one during the rainy season and three others during the dry season. The overall non-carcinogenic health in the urban rivers was considered high in regions with huge population and intense anthropogenic activity. The results showed the potential risk of some of the trace elements on human beings, especially on children. The main element contributor to non-carcinogenic risk was Cr, although Mn and Ni also contributed to non-carcinogenic risk in a few areas, mainly for children during the dry season.