Generation and dispersal of volcanic ash during explosive eruptions can impact the environment at a serious level. Ashfall on natural waters and water supplies produces turbidity, induces pH variations and alters the natural concentrations of chemical elements. Several eruptions have resulted in contamination of pasture, sometimes with serious impacts on livestock. The study was carried out on different samples ash leachates of different samples of volcanic ash, in order to evaluate the different release of chemical compounds in the environment. Samples from the eruptions of Mt. Etna (Sicily) of April 24, 2011 and August 12, 2012 and Popocatépetl 2012 (Mexico) represent an opportunity to study leachates on fresh and not yet rain-washed samples. Fresh samples have been characterised by XRF and XRD on bulk rock and SEM-EDS on glass and mineral phases. Leaching experiments were carried out using mQ-water and water samples from Lake Ohrid (Macedonia-Albania). Both waters were previously characterised using surface electrode, gas electrode, ion-chromatography and ICP-MS. During the experiments the pH variation, the concentration of chemical compounds and saturation index were determined. It was observed alkalinisation in Etna leachates samples and acidification in Popo leachates samples with different release of anions and cations; in particular Etna leachates are rich in F- and Popo leachates are rich in SO4-2. Many of the elements that have been measured are included in the drinking water guidelines due to their potential toxicity. In many of the analysed ash leachates F-, Mn+2, SO4-2 and Fe+2 concentrations exceed the maximum values defined by Italian law (for examples the maximum value of F is 1.5 mg/l, while F concentration in Etna ash leachates reaches the value of 20 mg/l),. Ash leachates were also used as living culture for tadpoles, and the stages of growth observed at different time intervals. The results highlight the potential impact of volcanic ash deposition on environment and human health.
D’Addabbo, M., Sulpizio, R., Guidi, G., Capitani, G., Mantecca, P. (2014). Environmental pollution from volcanic ash particulate: Examples of ash leachates from Mt. Etna (Italy) and Popocatepetl (Mexico) volcanoes. Intervento presentato a: DUST International Conference, Castellaneta Marina (TA), Italy.
Environmental pollution from volcanic ash particulate: Examples of ash leachates from Mt. Etna (Italy) and Popocatepetl (Mexico) volcanoes
CAPITANI, GIANCARLO;
2014
Abstract
Generation and dispersal of volcanic ash during explosive eruptions can impact the environment at a serious level. Ashfall on natural waters and water supplies produces turbidity, induces pH variations and alters the natural concentrations of chemical elements. Several eruptions have resulted in contamination of pasture, sometimes with serious impacts on livestock. The study was carried out on different samples ash leachates of different samples of volcanic ash, in order to evaluate the different release of chemical compounds in the environment. Samples from the eruptions of Mt. Etna (Sicily) of April 24, 2011 and August 12, 2012 and Popocatépetl 2012 (Mexico) represent an opportunity to study leachates on fresh and not yet rain-washed samples. Fresh samples have been characterised by XRF and XRD on bulk rock and SEM-EDS on glass and mineral phases. Leaching experiments were carried out using mQ-water and water samples from Lake Ohrid (Macedonia-Albania). Both waters were previously characterised using surface electrode, gas electrode, ion-chromatography and ICP-MS. During the experiments the pH variation, the concentration of chemical compounds and saturation index were determined. It was observed alkalinisation in Etna leachates samples and acidification in Popo leachates samples with different release of anions and cations; in particular Etna leachates are rich in F- and Popo leachates are rich in SO4-2. Many of the elements that have been measured are included in the drinking water guidelines due to their potential toxicity. In many of the analysed ash leachates F-, Mn+2, SO4-2 and Fe+2 concentrations exceed the maximum values defined by Italian law (for examples the maximum value of F is 1.5 mg/l, while F concentration in Etna ash leachates reaches the value of 20 mg/l),. Ash leachates were also used as living culture for tadpoles, and the stages of growth observed at different time intervals. The results highlight the potential impact of volcanic ash deposition on environment and human health.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
