Which metal represents the greatest risk to freshwater ecosystem in bohai region of china?

Abstract

Abstract. Metals discharged from industrial effluents, agricultural wastewater, and sewage runoff by rapid urbanization are of concern as contaminants of freshwater ecosystem because of their persistence and high toxicity to aquatic organisms. This study attempted to identify which metal posed the greatest risk to freshwater ecosystem in the Bohai Region, China. The metals arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), mercury (Hg), iron (Fe), and manganese (Mn) were compared against norfloxacin and gamma-hexachlorocyclohexane (lindane). By comparing the median reported environmental and ecotoxicity concentrations, it showed that Cu, Fe, Zn, Mn, and Cr were the top five metals of concern. Of these, Cu was deemed to represent the highest risk and Hg the lowest risk. The risks for all metals were higher than those for norfloxacin and lindane. Almost all the metals except Hg had water concentrations that exceeded levels where ecotoxicity effects had been recorded in the literature. A comparison with the measurements across the UK rivers suggested that all metals examined had water concentrations about 5-to 10-fold higher than the UK median values except for Cu, Fe, Cd, and Pb. The Fuyang River, a tributary of the Haihe River Basin, seemed to be the location with the highest metal concentrations. However, comparing the post-2010 period to [2000][2001][2002][2003][2004][2005][2006][2007][2008][2009], concentrations of all the metals had fallen except for Fe and Mn, so risks have decreased over the last 7 yr with the greatest improvements for Cd and Pb. While metals still pose high risks to freshwater ecosystem in this region, there is encouragement that some control measures are taken into effect.

Ecology of industrial pollution in China

“…Previous methods for ERA cannot meet the need for such a complex environmental context. Therefore, integrated ERA approach based on multi-pollutants, multi-media and multi-receptors at the regional scale has been developed, such as weighted assessment method (Yan et al 2018;Yu et al 2013), probabilistic ERA (Shi et al 2016) and relative risk ranking (Johnson et al 2018;Su et al 2017;Zhang et al 2017bZhang et al , 2017c. These integrated ERA approaches pay attention not only to the chemical pollutants but also to the interaction with physical and biological stressors ( Figure 6).…”

Sensors Applied for the Detection of Pesticides and Heavy Metals in Freshwaters

“…Zn, Mn, and Cr were the top five heavy metals of concern in freshwaters in Bohai Region, China, while Hg showed the lowest risk [193]. The concentrations of many heavy metals in the river Ganga water and sediment exceeded the acceptable concentrations and threatened human health and aquatic organisms [194].…”

Ranking Ecological Risk of Metals to Freshwater Organisms in Lake Taihu, China

“…When the probability method was applied, the metals that posed high risks to aquatic organisms were Cu, Ni, Zn, Cd, Pb, and Cr. In previous reports, Cu and Zn have also been identified as the metals posing the greatest risks to freshwater ecosystems in the UK [9], in Lake Taihu, and in the Bohai Region of China [25,26] though the studies adopted different approaches. Notably, Al, which was reported in the first or second place in the order of risk in UK river water when water chemistry is not considered, was not targeted in the present study [7,9].…”