Pollution Characteristic And Risk Assessment Of Heavy Metals And Fluoride In Drinking Water Sources

The core issue of water environment protection is the guarantee of drinking water source.Heavy metal pollution is particularly sensitive to the health and the safety of drinking.Liangyungang is located in the ending of Huai river basin,along with the implementation of South-to-North Water Diversion and and the rapid development of social economy in Northern Jiangsu province,the protection of drinking water quality has become an important factor restricting the goal of Lianyungang.According to the planning of Lianyungang City drinking water source and the principle of uniform layout along the way,we set eight sediment sampling sites and and collected soil samples.According to the analysis results of water quality,we determined heavy metals of sediment and soil.The content and distribution of heavy metals in sediment samples were analyzed in the paper.We analyze the contents of heavy metals in sediments,study on the morphological distribution and migration ability and evaluate ecological risk of heavy metal pollution of water sources.Use multivariate statistical analysis to research the source of heavy metals and fluoride.According to the distribution characteristics of heavy metals in sediments,the distribution characteristics and migration ability of heavy metals in sediments were resolved.The risk assessment of heavy metal pollution in water source was carried out in this paper.The main content and results are as follows:1.By contrast with the average content of heavy metals in sediment and soil selected background values,the average of all the elements in sediment exceeded the background value in sediment and the average of Cd,Cu,Hg,Pb and Zn elements exceed the background value in soil.The content of Cd,Cu,Hg,Pb and other elements in the upper reaches of drinking water sources have been affected by human activities in different degrees.2.Analysis sources of heavy metals based on multivariate statistics:By using the correlation analysis,the correlation coefficient of Cd,Cu and Zn is higher,and it has the same source.Principal component analysis showed that Cu,Pb and Zn in the first principal component,reflecting their enrichment and source.Cluster analysis showed that the first category includes As,Cd,Cu,Hg and Pb,the second category includes Cr and Zn,the third category includes fluoride.Source of the same class element is consistent.3.Cd mainly existed as carbonate phase and Fe-Mn oxide forms.The highest proportion of Zn is residual forms.Zn is the most stable element under normal environmental conditions.Six kinds of heavy metal migration from high to low are:Cd>As>Ni>Cu>Pb>Zn.Cd is considered to be a high risk factor for the release of sediment to the water.It is easy to release to water body when the conditions of pH and coexisting ions are changing.Compared with other heavy metals,Cd comprehensive pollution coefficient is relatively high,especially in soil.Compared with the evaluation results based on the heavy metal speciation,the comprehensive pollution coefficient is consistent with the result of the migration ability.Cd in high water period is significantly higher than those in the dry season,and it consistent with sediment migration.4.Using Pearson correlation analysis the relationship between fluoride and constant,heavy metal elements.P is a common factor affecting the fluoride pollution in sediment and soil.Fluoride and other heavy metals have a significant correlation and they have the same origin.From the evaluation results,fluoride in sediment and soil is in the mild pollution levels of Lianyungang drinking water source.5.Based on August 2014 to 2015 October Shu Xin Qu section of the water quality monitoring data,this paper selected the toxicological and chemical index meet the "Standards for Drinking Water Quality"(GB5749-2006).Water pollution does not produce negative effects and there is no risk of contamination from the source of life in rural areas,industrial pollution and bridges risk source.Overall,Lianyungang drinking water sources of heavy metals are in the moderate pollution levels based on the pollution source of Shuxin canal.The water quality of drinking water source has a certain degree of ecological risk.This paper researched heavy metals and fluoride in different environmental media of the upper reaches of the drinking water source in Lianyungang.It has important practical significance and in order to provide the basis for the water source of persistent pollution.