In vitro and in vivo toxicity of coal fly Ash Lechate

Abstract

Coal Fly ash is a major solid waste from coal-fired power stations. In Brazil, more than 4 million tons per year of fly ash are generated and only 30% is applied as raw material for cement and concrete production. The remaining is disposed in on-site ponds, nearby abandoned or active mine sites and landfills. The inadequate disposal of fly ash may pose a significant risk to the environment due to the possible leaching of hazardous pollutants into the surrounding soil and groundwater. A combination of leaching tests, cytotoxicity and ecotoxicological assays were used in this studyin order toevaluate the possible adverse effects of coal fly ash in non-target organisms. The sample was collected from coal-fired power plant located in Southern Brazil and the coal fly ash was submitted to a leaching procedure using USEPA SW 864 Method 1311. The leachate was prepared in six dilutions: 1.56%, 3.12%, 6.25%, 12.5%, 25% and 50%. Acute toxicity tests were performed on NCTC clone 929 (CCIAL-020) culture cells by neutral red uptake cytotoxicity method; acute ecotoxicity usingDaphnia similisand Danio rerio embryos according to ABNT NBR 12713 and OECD 236, respectively were employed. The cytotoxicity index (CI 50 ) obtained was 33%; the EC 50 of D. similis after 48 h of exposure to the leachate was 7.25% and the LC 50 of D. rerio after 96 h of exposure was 4.39%. The results of these bioassays indicated toxicity of the coal fly ash leachate toward exposed organisms.

Comparative Toxicity of Fly Ash: An In Vitro Study

“…The physicochemical and cytotoxic properties of fly ash of various origins are actively studied [ 21 , 22 , 23 ]. The harmful effects of coal fly ash were previously attributed to the presence of trace elements [ 24 ] as well as the particle size distribution of the samples [ 25 , 26 ]. Here, we analyzed the alumosilicate fly ash microparticles collected from several electric power stations and a metallurgic plant and assessed their toxicity in vitro using the HeLa cells (human cervical cancer cells) and Jurkat cells (immortalized human T lymphocytes), typical models in numerous cell culture-based experiments.…”