Characterization of Chlorinated Aliphatic Hydrocarbons and Environmental Variables in a Shallow Groundwater in Shanghai Using Kriging Interpolation and Multifactorial Analysis

Abstract

CAHs, as a cleaning solvent, widely contaminated shallow groundwater with the development of manufacturing in China's Yangtze River Delta. This study focused on the distribution of CAHs, and correlations between CAHs and environmental variables in a shallow groundwater in Shanghai, using kriging interpolation and multifactorial analysis. The results showed that the overall CAHs plume area (above DIV) was approximately 9,000 m2 and located in the 2–4 m underground, DNAPL was accumulated at an area of approximately 1,400 m2 and located in the 6-8m sandy silt layer on the top of the muddy silty clay. Heatmap of PPC for CAHs and environmental variables showed that the correlation between “Fe2+” and most CAHs such as “1,1,1-TCA”, “1,1-DCA”, “1,1-DCE” and “%TCA” were significantly positive (p<0.001), but “%CA” and/or “%VC” was not, and “Cl-” was significantly positive correlated with “1,1-DCA” and “1,1-DCE” (p<0.001). The PCA demonstrated that the relative proportions of CAHs in groundwater were mostly controlled by the sources and the natural attenuation. In conclusion, the combination of geographical and chemometrics was helpful to establishing an aerial perspective of CAHs and identifying reasons for the accumulation of toxic dechlorination intermediates, and could become a useful tool for characterizing contaminated sites in general.

Enzymatic assays for the assessment of toxic effects of halogenated organic contaminants in water and food. A review

“…Bioaccumulation of CAHs has also been reported and trace concentrations of CAHs have been found in species like Pacific Walrus (Odobenus rosmarus divergens) (Seagars and Garlich-Miller, 2001). CAHs contamination is associated with anthropogenic activities, specifically, improper handling and release into the ecosystem, resulting in toxic and carcinogenic exposures (Guha et al, 2012;Leisinger, 1996;Lu et al, 2015).…”

“…Several examples of bioaccumulation and transference to higher trophic levels can be found for chlorinated organic compounds. The Yangtze River Delta (China) has been exposed to several soil and groundwater contamination incidents, leading to accumulation of CAHs (Lu et al, 2015).…”

Petroleum hydrocarbon rich oil refinery sludge of North-East India harbours anaerobic, fermentative, sulfate-reducing, syntrophic and methanogenic microbial populations

“…Nevertheless, eco-friendly, cost-effective and sustainable microbe-based in situ bioremediation of contaminated sites has gained considerable importance, as bioremediation technology is relying on the metabolic activity of the native microbial populations contributing in hydrocarbon mineralization through natural biogeochemical cycles [ 5 , 6 ]. However, the diversity, distribution and activity of native microbial communities are determined by the prevailing environmental factors of the contaminated sites to thrive in such inhospitable conditions [ 7 , 8 ]. Therefore, characterization of contaminated sites and inhabitant microbial populations have been considered as essential prerequisites for the development of bioremediation strategies as the success of bioremediation is very much influenced by the available physicochemical conditions and nutrient availability [ 9 – 11 ].…”

Prediction of Dichloroethene Concentration in the Groundwater of a Contaminated Site Using XGBoost and LSTM

“…As an important chemical raw material and organic solvent, chlorinated aliphatic hydrocarbons (CAHs) are widely used in agriculture and industries [ 1 ]. Due to improper storage and disposal, CAHs could enter the groundwater through volatilization, leakage, and discharge, and have been investigated in many studies [ 2 , 3 , 4 , 5 ].…”