Acute and chronic activity of perchlorate and hexavalent chromium contamination on the survival and development of Culex quinquefasciatus Say (Diptera: Culicidae)

2006 ◽  
Vol 144 (3) ◽  
pp. 759-764 ◽  
Author(s):  
Mary A. Sorensen ◽  
Peter D. Jensen ◽  
William E. Walton ◽  
John T. Trumble
Keyword(s):  
Hexavalent Chromium ◽  
Culex Quinquefasciatus ◽  
Chromium Contamination ◽  
Survival And Development

scholarly journals Analysis of Hydrogeochemical Characteristics and Origins of Chromium Contamination in Groundwater at a Site in Xinxiang City, Henan Province

2021 ◽  
Vol 11 (24) ◽  
pp. 11683
Author(s):  
Wenfang Chen ◽  
Yaobin Zhang ◽  
Weiwei Shi ◽  
Yali Cui ◽  
Qiulan Zhang ◽  
...  
Keyword(s):  
Hexavalent Chromium ◽  
Groundwater Remediation ◽  
Saturation Index ◽  
Shallow Groundwater ◽  
Distribution Patterns ◽  
Scientific Basis ◽  
Henan Province ◽  
Contaminated Site ◽  
Control Mechanisms ◽  
Chromium Contamination

Hexavalent chromium contamination in groundwater has become a very serious and challenging problem. Identification of the groundwater chemical characteristics of the sites and their control mechanisms for remediation of pollutants is a significant challenge. In this study, a contaminated site in Xinxiang City, Henan Province, was investigated and 92 groundwater samples were collected from the site. Furthermore, the hydrogeochemical characteristics and the distribution patterns of components in the groundwater were analyzed by a combination of multivariate statistical analysis, Piper diagram, Gibbs diagram, ions ratio and hydrogeochemical simulation. The results showed that the HCO3-Cl-Mg-Ca type, SO4-HCO3-Na type, and HCO3-Mg-Ca-Na type characterize the hydrogeochemical composition of shallow groundwater and HCO3-Cl-Mg-Ca type, HCO3-Na-Mg type, and HCO3-SO4-Mg-Na-Ca type characterize the hydrogeochemical composition of deep groundwater. Ion ratios and saturation index indicated that the groundwater hydrogeochemical characteristics of the study area are mainly controlled by water–rock action and evaporative crystallization. The dissolution of halite, gypsum and anhydrite, the precipitation of aragonite, calcite and dolomite, and the precipitation of trivalent chromium minerals other than CrCl3 and the dissolution of hexavalent chromium minerals occurred in groundwater at the site. The minimum value of pH in groundwater at the site is 7.55 and the maximum value is 9.26. The influence of pH on the fugacity state of minerals was further investigated. It was concluded that the saturation index of dolomite, calcite, aragonite and MgCr2O4 increases with the increase of pH, indicating that these minerals are more prone to precipitation, and the saturation index of Na2Cr2O7, K2Cr2O7 and CrCl3 decreases with the increase of pH, implying that Na2Cr2O7, K2Cr2O7 and CrCl3 are more prone to dissolution. The saturation index of the remaining minerals is less affected by pH changes. The study can provide a scientific basis for groundwater remediation.

Calcium polysulfide remediation of hexavalent chromium contamination from chromite ore processing residue

2006 ◽  
Vol 364 (1-3) ◽  
pp. 32-44 ◽  
Author(s):  
Margaret C. Graham ◽  
John G. Farmer ◽  
Peter Anderson ◽  
Edward Paterson ◽  
Stephen Hillier ◽  
...  
Keyword(s):  
Hexavalent Chromium ◽  
Chromite Ore Processing Residue ◽  
Chromite Ore ◽  
Chromium Contamination ◽  
Ore Processing ◽  
Calcium Polysulfide

scholarly journals Hazardous Waste Disposal in Stromatolitic-Limestone Terrain and Hexavalent Chromium Contamination in Chhattisgarh State, India

2020 ◽  
Vol 10 (27) ◽  
pp. 200907
Author(s):  
Alka Banchhor ◽  
Madhurima Pandey ◽  
Meena Chakraborty ◽  
Piyush Kant Pandey
Keyword(s):  
Environmental Health ◽  
Hazardous Waste ◽  
Hexavalent Chromium ◽  
Water Discharge ◽  
Contaminated Water ◽  
Chromite Ore Processing Residue ◽  
Chromite Ore ◽  
Chromium Contamination ◽  
Ore Processing ◽  
Hazardous Waste Landfills

Background. Hexavalent chromium-containing waste from chromite ore processing is a major environmental health hazard due to its high toxicity. There have been instances of improper and unsafe disposal of this waste, leading to environmental health hazards. Objectives. The objective of the present study was to identify the cause of yellow colored water discharge and reported health issues in nearby residents and cattle. In addition, it investigated the improper disposal of chromite ore processing residue (COPR), a hazardous waste, in an abandoned quarry in stromatolitic-limestone terrain in central-east India. Methods. Standard methods of analysis of water and wastewater were used for the analyses of variables, including hexavalent chromium (Cr(VI)), pH, sulfate (SO42−), chlorine (Cl−), total hardness, calcium (Ca(II)), magnesium (Mg(II)), alkalinity and sodium (Na(I)) with proper sampling, quality assurance, and quality control protocols. Onsite Cr(VI) was analyzed using a chromium testing kit, and in the laboratory by atomic absorption spectrophotometry. Results. Large-scale contamination of surface and groundwater was noted due to the migration of hexavalent chromium-contaminated yellow colored leachate. High levels of hexavalent chromium were noted in the samples. The maximum Cr(VI) concentration observed was 1050 mg/L in leachate, 22 mg/L in surface water and 0.26 mg/L in the groundwater sample. Acute health effects were noted in cattle and by residents who consumed the highly contaminated water. Conclusions. A large volume of discharge of hexavalent chromium contamination from the COPR landfill was found, indicating the absence of containment features in the design (double high-density polyethylene liners, clay, leachate collection). Disposal of COPR in an abandoned limestone mine is inadvisable. The highly fractured stromatolitic-limestone environment at the study site was found to offer almost no resistance to the mobilization of Cr(VI) due to the absence of organic or eukaryotic deposition in the stromatolitic environment. It was also noted that the drainage pattern of the area facilitates a possible translocation of contaminated discharge to the nearby river system. Nearby residents were unaware of the adverse impacts of the contaminated leachates and were using the contaminated water for bathing, washing, etc. Applicable Indian governmental regulations regarding the construction of hazardous waste landfills were found to be insufficient with respect to the use of inactive limestone mines as landfill sites. Competing Interests. The authors declare no competing financial interests.

Effect of Pb, Cd and Cu on survival and development of Culex quinquefasciatus (Diptera: Culicidae)

2020 ◽  
Vol 36 (3) ◽  
pp. 205-219
Author(s):  
Ikram Ilahi ◽  
Ali Muhammad Yousafzai ◽  
Hazrat Ali
Keyword(s):  
Culex Quinquefasciatus ◽  
Survival And Development
Sign in / Sign up

Export Citation Format

Share Document