| Title | Enhancement of Microbial-Mediated Cr(VI) Reduction Processes for Recovering Contaminated Groundwater |
| Abstract | Groundwater Cr (VI) pollution largely depends on industrial applications in the field of energy production, manufacturing of metals and chemicals, tanning, and subsequent waste and wastewater management. Cr(VI) is a hazardous environmental pollutant, because of its mobility and toxicity, especially for mammalian cells, which do not have efficient chromate detoxifying pathways. On the contrary, chromate-reducing genes are widely present in prokaryotes which can reduce Cr(VI) to the less toxic and less mobile Cr(III). Bioremediation represents a valid alternative to chemical methods which are ineffective at lower concentrations of Cr(VI) in large volumes of wastewater and could generate secondary pollution. Nevertheless, the biological treatment of Cr(VI) contaminated groundwaters is limited, because most known species capable of chromate reduction are heterotrophic, and need extra nutrition addition during the reduction process, especially in an oligotrophic groundwater environment. The aim of this work was to evaluate the extent of Cr(VI) reduction by groundwater indigenous microorganisms at a laboratory scale, aimed at potential application for in situ recovery of the industrial area of Barletta Municipality (Southern Italy). In 2020, two monitoring campaigns carried out on the study site revealed a Cr(VI) concentration in groundwater above the legal limit (Italian environmental law, D.Lgs. 152/06), ranging from 50 to 102 µg L -1 . Microcosms have been set up with groundwater and water-saturated soil, collected from the above-mentioned industrial area. Different experimental conditions have been tested, as follows: biological batch, biological batch with two different amendments and, the corresponding sterile controls. Specifically, the amendments employed in the microcosms' set up, were: 1) yeast extract, that resulted efficient in promoting a quick Cr(VI) bioreduction in our previous laboratory study; 2) polyhydroxybutyrate, that is well-known in scientific literature as a slowrelease substrate for enhancing biological reduction in bioremediation processes. A multidisciplinary approach has been performed to elucidate microbial-mediated Cr(VI) reduction processes. Changings in microbial abundance have been evaluated via Real-Time PCR in parallel with chemical and spectrophotometric analyses for monitoring Cr(VI) concentration. FTIR spectroscopy has been used to investigate chromium forms in microcosms solid phase. |
| Source | GLOBAL CHALLENGES. AN EMERGENCY FOR ENVIRONMENTAL SCIENCES., virtual congress, 03/05/2021- 06/05/2021 |
| Keywords | chromiummicrobial reduction |
| Year | 2021 |
| Type | Abstract in atti di convegno |
| Authors | M. Tumolo, C. Campanale, De Palma D., V.F. Uricchio, P. Cotugno, A. Tursi, V. Ancona |
| Text | 453817 2021 chromium microbial reduction Enhancement of Microbial Mediated Cr VI Reduction Processes for Recovering Contaminated Groundwater M. Tumolo, C. Campanale, De Palma D., V.F. Uricchio, P. Cotugno, A. Tursi, V. Ancona IRSA CNR UNIBA ABSTRACT BOOK SETAC EUROPE 31 ST ANNUAL MEETING Society of Environmental Toxicology and Chemistry Europe SETAC Europe Published version GLOBAL CHALLENGES. AN EMERGENCY FOR ENVIRONMENTAL SCIENCES. virtual congress 03/05/2021 06/05/2021 Internazionale Contributo Groundwater Cr VI pollution largely depends on industrial applications in the field of energy production, manufacturing of metals and chemicals, tanning, and subsequent waste and wastewater management. Cr VI is a hazardous environmental pollutant, because of its mobility and toxicity, especially for mammalian cells, which do not have efficient chromate detoxifying pathways. On the contrary, chromate reducing genes are widely present in prokaryotes which can reduce Cr VI to the less toxic and less mobile Cr III . Bioremediation represents a valid alternative to chemical methods which are ineffective at lower concentrations of Cr VI in large volumes of wastewater and could generate secondary pollution. Nevertheless, the biological treatment of Cr VI contaminated groundwaters is limited, because most known species capable of chromate reduction are heterotrophic, and need extra nutrition addition during the reduction process, especially in an oligotrophic groundwater environment. The aim of this work was to evaluate the extent of Cr VI reduction by groundwater indigenous microorganisms at a laboratory scale, aimed at potential application for in situ recovery of the industrial area of Barletta Municipality Southern Italy . In 2020, two monitoring campaigns carried out on the study site revealed a Cr VI concentration in groundwater above the legal limit Italian environmental law, D.Lgs. 152/06 , ranging from 50 to 102 µg L 1 . Microcosms have been set up with groundwater and water saturated soil, collected from the above mentioned industrial area. Different experimental conditions have been tested, as follows biological batch, biological batch with two different amendments and, the corresponding sterile controls. Specifically, the amendments employed in the microcosms set up, were 1 yeast extract, that resulted efficient in promoting a quick Cr VI bioreduction in our previous laboratory study; 2 polyhydroxybutyrate, that is well known in scientific literature as a slowrelease substrate for enhancing biological reduction in bioremediation processes. A multidisciplinary approach has been performed to elucidate microbial mediated Cr VI reduction processes. Changings in microbial abundance have been evaluated via Real Time PCR in parallel with chemical and spectrophotometric analyses for monitoring Cr VI concentration. FTIR spectroscopy has been used to investigate chromium forms in microcosms solid phase. Abstract in atti di convegno claudiacampanale CAMPANALE CLAUDIA marinatumolo TUMOLO MARINA vitofelice.uricchio URICCHIO VITO FELICE valeria.ancona ANCONA VALERIA domenico.depaola DE PAOLA DOMENICO |
