Detail Abstract

Potential impact of global warming by effect of temperature on toxicity of Pb on aquatic life

Abstract

Lakes in the Hanoi urban area have been facing many environmental problems, such as 1) lack of water; 2) high turbidity from organic materials and garbage; 3) pollution from heavy metals and artificial organic chemicals; 4) algae blooms; and 5) biodiversity degradation.<br> Heavy metal pollution in urban lakes of Hanoi has become one of the major environmental issues in the last decades. Lead (Pb) is a heavy metal found in significant concentrations in the waters of Hanoi lakes and accumulates in the aquatic animals. Research on the toxicity of Pb is necessary due to the extent of its harm to aquatic ecosystems. The toxicity of Pb to aquatic organisms (determined through EC50 values) depends on different environmental conditions. The study was conducted to evaluate the effect of temperature on the toxicity of Pb on the test organism Moina Dubia, which is indigenous to the lake in Hanoi. Moina Dubia was cultured under laboratory conditions and has been used to conduct EC50 determination for Pb. Moina Dubia belongs to the Cladocera group (Cladocera) which is an indigenous creature collected at Lake Hanoi. The research process shows that Moina Dubia grows and develops well in the laboratory and is suitable as a test organism in toxicological studies. A survey of 24OC and 28OC temperature conditions shows that when the temperature increases, the EC50 value decreases, so higher water temperature is a factor that increases the toxicity level of Pb on Moina Dubia<br> Due to global climate change, the trend of increasing the ambient temperature is in red River Delta had been reported. As the consequence, the increase of water temperature in aquatic bodies can be observed. Clear impact of water temperature on toxicity of heavy metal as Pb showed that global warming may lead to the increase of toxicity of the heavy metal of aquatic bodies.<br> Results of this study strongly recommend for comprehensive approaches to improve environmental conditions in urban lakes of Hanoi.