| With the rapid development of economy and society,the water quality of the Yellow River decreased obviously.Gansu Province,Ningxia and the Inner Mongolia Autonomous Region(hereinafter referred to as Gan-Ning-Meng region)are typical arid or semi-arid areas with agricultural and industrial developing where are considered as one of China's important industrial bases.The increase of regional ecological risk of Gan-Ning-Meng region must make the heavy metal pollution of Gan-Ning-Meng sections of the Yellow River worse.The research objects of this paper are the surface water,sediments of the Yellow River and the local residents' hair which sampled from the representative sampling sites(the junctions of the Yellow River and Gan-Ning-Meng boundaries).The research content is the concentration levels of As,Cd,Cr,Cu,Fe,Mn,Pb,Zn in the samples,the research purpose is to evaluate the content distributions and pollution status of heavy metals in different media,and discuss the characteristics of adsorption and desorption of Cr and Pb onto the sediments by using inductively coupled plasma mass spectrometry(ICP-MS).This paper could provide experimental data and scientific basis for protecting the Yellow River water and solving the public and the environment of the health problems in North-West China.The results showed:The highest concentration level of heavy metals of filtered water showed in the site P3,the average values of metals followed the order:Fe>Mn>Zn>Pb>Cu>Cr>As>Cd.The evaluation results of water quality index method and comprehensive pollution index method showed that the water quality were clean except for site P3.8 metals in this study showed the highest levels in site P3,although few factories built around there,site P3 is located in the lower reach of two major industrial cities-Lanzhou and Baiyin,which may lead to the high concentrations of heavy metals such as Pb and Cd.The research on the provincial flux suggested that there were new pollution sources around site P3 because of the increase of metals levels of the Yellow River water in Gansu section.Compared with upper reaches and lower reaches of the Yellow River,the water quality of Cd,Cr,Cu,Zn and other elements of upper reaches were better than that of this paper and lower reaches.The research results of concentration levels of surface sediments revealed that the metals contents in all sampling sites followed the order of Fe>Mn>Zn>Cr>As>Pb>Cu>Cd.It can be seen that there were tiny differences among different sampling sites,which is because the sediment is a very stable pollutant carrier.Refer to the local soil background values,the index of Geoaccumulation(Igeo)showed that moderate pollution for Cd in site P2,a intermediate pollution for Cd in P1,P3 and P4,and As in P1-P4,a slight pollution for Zn in P2.The potential ecological risk index(RI)evaluation results showed that the R1 values followed as P2(247.84)>P3(216.26)>P4(206.05)>P1(175.01),this suggested that the ecological risks of heavy metals in surface sediments were in moderate levels.The sediments enrichment factor method(EF)showed that the Cd and As of the four sampling sites had strong pollution,and it was caused by human activities.Comparison with the references,the most polluted elements in this paper was As,it was about 5 times of background value of the loess material,20 times of the middle reaches of the Yellow River.The results of hair metals analysis showed that the Cr concentrations were significantly high in the 4 sampling sites,which indicated that the Gan-Ning-Meng region probably had a high level of Cr exposure.There are significantly differences between female and male of Mn(p=0.001)and Fe(p=0.001)concentrations.The levels of Mn and Fe were significantly higher in female than in male,which may be caused by the differences in the intake of trace elements in food,thus affected the absorption and bioavailability of trace metals.For different age groups,Cr(p=0.021),Zn(p=0.003)and Pb(p=0.035)showed significant differences.Among them,the Pb concentration level in the young group was the highest,followed the middle-aged group,the lowest showed in the elderly group.Correlation analysis of biological samples and environmental samples showed significant negative correlation of Mn and Cr between in human hair and in sediments.Adsorption-desorption characteristics results of Pb(?)and Cr(?)onto surface sediments of Hequ section of the Yellow River showed that the adsorbtion had a low adsorption efficiency under strong acidity.When pH=6,the adsorption efficiency reached the maximum.The adsorption rates of Pb(?).and Cr(?)increased very quickly,with the time prolonging,the adsorption rate changed slowly,and reached the adsorption equilibrium at 60 min.Kinetic experiments showed that the adsorption processes of Pb(?)and Cr(?)were in accordance with Pseudo-second-order kinetics model,and the adsorption processes were mainly chemical adsorption.Adsorption isotherm experiments showed that the Pb(?)adsorption process was consistent with the Langmuir model,and Cr(?)was consistent with the Freundlich model.Thermodynamic results showed that the adsorptions of Pb(?)and Cr(?)were endothermic and spontaneous.The adsorbed Pb(?)and Cr(?)desorption slowly,reached basic balance at about 360min,and Cr(?)desorption was greater than Pb(?).The desorptions of the two metals were in accordance with the Elovich equation,which belonged to heterogeneous diffusion.The desorption amount decreased with the increase of pH.Competitive adsorption of coexisting ions showed that Pb(?)adsorption was better than Cr(?)onto sediment,and the competitive adsorption rates of Pb(?)and Cr(?)were lower than that of single ion in the coexistence system.The results of this study could provide experimental data and scientific basis for establishing the corresponding ecological compensation mechanism,protecting the Yellow River water and solving the problems of public and environmental health in North-West China. 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