BIO-VOLCANO: PRELIMINARY DATA FROM MT. ETNA EXPEDITION

Mercury is one of the more harmful pollutants emitted by active volcanoes. Mercury has a long residence time in the atmosphere which holds a potentially negative impact on the health of communities living in the shadow of volcanic systems. Therefore, exploring the mercury emission route to the accumulation in organic and inorganic material has the potential to impact the safety precautions of those who live in the proximal areas to volcanic systems. This study aims to evaluate the possible correlation between the eruption intensity and magnitude to the total mercury concentration in organic and inorganic materials (plants, soils, and tephra) using Mt. Etna (Sicily, Italy) as the exemplary volcanic emitter of mercury during explosive eruptive activity. Specifically, volcanic tephra from paroxysm events of February 10 and 22, 2022, chestnut leaves, and soils were collected at fifteen different sites around the volcano in June 2022. Total mercury concentration was measured in representative samples of volcanic tephra, chestnut leaves, and soils at the Center for Applied Isotope Studies at UGA. The analysis shows that soils are exceptional mercury recorders in their top 5-cm layer. Conversely, the chestnut leaves do not display a clear correlation between Hg concentration and recent paroxysms of February 10 and 22, 2022 at Mt Etna. Finally, volcanic rocks display minimal mercury concentration, suggestive that mercury is largely partitioned in the volcanic gas emissions and rapidly accumulates in soils. Statistical analysis based upon the laboratory data and the interpretations of the p-values prove that there is a statistically significant relationship between the amount of mercury and the elevation at which the soil sample was collected, meaning that the former is dependent on the latter. Also, there is evidence of a positive correlation between of the amount of mercury and the distance from the main active vent, with soil samples carrying the average bulk of the concentration between the three mediums. This evidence can be used to conduct further research into establishing a predictive model for the amount of mercury released to the size of the volcanic eruption, thus proposing mercury dispersion and accumulation as possible monitoring parameters in volcanic hazard assessment.