Evaluating the metallic pollution of riverine water and sediments: a case study of Aras River

Abstract

Metallic pollution caused by elements Zn, Cu, Fe, Pb, Ni, Cd, and Hg in water and sediments of Aras River within a specific area in Ardabil province of Iran is considered. Water and sediment samples were collected seasonally and once respectively from the five selected stations. Regarding WHO published permissible values, only Ni concentration in spring and summer water samples has exceeded the acceptable limit up to four times greater than the limit. The concentration of metals Ni, Pb, and Fe in river water shows a direct relationship with river water discharge and the amount of precipitation. Enhanced soil erosion, bed load dissolution, and runoffs may play a key role in remarkable augmentation of metallic ions concentration. Furthermore, excessive use of pesticides which contain a variety of metallic ions (mainly Cu) in spring and summer may also result in an increase in the metals' concentration. The potential risk of Ni exposure to the water environment of the study area is assigned to juice, dairy products, edible oil, and sugar cane factories as well as soybean crop lands which are located within the sub-basin of Aras River in the study area. Regarding the sediment samples, the bioavailable metal concentrations indicate an ascending order from the first station towards the last one. In comparison with earth crust, sedimental and igneous rocks the reported metallic concentration values, except for Cd, lie within the low-risk status. Regarding Cd, the reported values in some stations (S2, S4, and S5) are up to ten times greater than that of shale which may be considered as a remarkable risk potential. The industrial and municipal wastewater generated by Parsabad moqan industrial complex and residential areas, in addition to the discharges of animal husbandry centers, may be addressed as the key factors in the sharp increase of metallic pollution potential in stations 4 and 5.

Heavy metal concentrations and ecological risk assessment of the suspended sediments of a multi-contaminated Brazilian watershed

“…Heavy metal contamination in suspended sediments is of particular concern due to its potential risks to human health and aquatic organisms (Silva et al, 2017). Metal contamination is traceable to a variety of sources, including sugarcane farming (which involves the high use of vinasse, pesticides and mineral fertilizers), domestic sewage, and wastewater from industrial and agricultural operations (Gunkel et al, 2007;Nasehi, Hassani, Monavvari, Karbassi, & Khorasani, 2013).…”

What is happening to our Lagoons? The example of Butuah Lagoon in Ghana

“…Most lagoons are polluted, mainly from anthropogenic waste input, because they lack proper watershed management strategies [1,2,4]. Among the major pollutants recorded in different lagoons around the world are heavy metals [4][5][6].…”

“…Among the major pollutants recorded in different lagoons around the world are heavy metals [4][5][6]. Heavy metals are very harmful, due to their [1,2,4] toxicity, persistence and deleterious impact on aquatic life and human health [5,6].…”

“…(3) Do the concentrations of heavy metals recorded in the sediment and water samples differ among the sampling stations? and (4) what is the degree of heavy metal pollution in the sediment as indicated by assessment index? The study provides information that could help in the development of management strategies and create awareness to other stakeholders.…”

Ecological risk assessment of metals contamination in the sediment of the Bamdezh wetland, Iran

“…Inputs of heavy metals and other pollutants to the coastal areas are likely increasing because of economic growth in Asian countries (Nasehi et al 2012). Heavy metals and petroleum hydrocarbons are considered as a common environmental contamination and a worldwide concern .…”