The Characteristics Of Rare Earth Elements And Anthropogenic Gadolinium(Gd) Anomalies In The Surface Water Of Wuhan

In a broad sense,rare earth elements consist of 16 key elements,including Y,Sc,and 14 niobium elements from La to Lu.Traditional geochemistry studies of rare earth elements often use rare earth elements as tracers for rivers.Besides with the development of science and technology,Rare earth elements?REEs?are widely used in various fields because of their unique physical and chemical properties.With the increasing use of REEs,there are obvious anomalies found in many rivers around the world.In order to evaluate the distribution characteristics of rare earth elements in surface water in Wuhan City and the source of anthropogenic Gd anomalies,this study collected surface water samples from Wuhan City and measured the data of REEs using inductively coupled plasma mass spectrometry?ICP-MS?.The main conclusions are as follows:?1?The total amount of rare earth elements in the surface rivers of Wuhan city was between 6.76-163.88 ng L^-1 and the total amount of rare earth elements in lakes was between 15.74-88.85 ng L^-1.The total concentration of rare earth elements in the water of Wuhan is lower than that of the world's fresh water.In Fuhe River?FH?Xunsihe River?XSH?and Lake Jinyin,Lake East and Lake South showed high concentrations of total rare earth elements associated with the high concentration of Gd elements imported by anthropogenic Gd.?2?As can be seen from Post Archean Australian Shale?PAAS?normalized REE patterns,in rivers and lakes,all rivers and lakes show the characteristics of the distribution pattern of heavy rare earths relative to light rare earth enrichment,medium rare earths relative to light rare earths and heavy rare earth enrichment.The characteristics of normalized REE patterns in the surface rivers and lakes of Wuhan are the result of the joint control of its geological and hydrochemical processes.Samples of all rivers and parts of the lake showed negative Ce anomalies and positive Eu abnormalities.South Lake,Huangjia Lake and East Lake did not show significant Ce abnormalities,mainly due to Ce O₂ precipitation,mainly adsorption on the fine colloid,still as part of the solution.?3?In addition,the study also found that there are obvious Gd anomalies in surface water in Wuhan,rivers and lakes.The concentration of anthropogenic Gd is calculated by interpolation,varying more than two orders of magnitude from 1.11 to157.51 ng L^-1.Fuhe River and Xunsihe River?XSH?anthropogenic Gd account for97.04%and 92.25%,respectively.The Lake East and Lake South both accounted for94%of the anthropogenic Gd.Studies have shown that these high concentrations of anthropogenic Gd come directly from the water from the wastewater treatment?WWTP?,dating back to the original source of Gd contrast agents used in hospital magnetic resonance imaging?MRI?.With the continuous development of medical level,the load of anthropogenic Gd in the surface water system in Wuhan will continue to increase.It is of great scientific significance to study and monitor the distribution of Gd in the basin.?4?On the Fuhe River,as the distance from the water from the wastewater treatment increases the concentration of anthropogenic Gd elements,which may be related to the self-purification effect of the river.It can be seen that the anthropogenic Gd has obvious indicative effect on the drainage of urban sewage treatment plant,and has the potential to be an indicator of the degree of natural water being affected by urban wastewater in the future.