Estimates of volcanic mercury emissions from Redoubt Volcano, Augustine Volcano, and Mount Spurr eruption ash

Ash is a potential sink of volcanically sourced atmospheric mercury (Hg), and the concentration of particle-bound Hg may provide constraints on Hg emissions during eruptions. We analyze Hg concentrations in 227 bulk ash samples from the Mount Spurr (1992), Redoubt Volcano (2009), and Augustine Volcano (2006) volcanic eruptions to investigate large-scale spatial, temporal, and volcanic-source trends. We find no significant difference in Hg concentrations in bulk ash by distance or discrete eruptive events at each volcano, suggesting that in-plume reactions converting gaseous Hg0 to adsorbed Hg2+ are happening on shorter timescales than considered in this study (minutes) and any additional in-plume controls are not discernable within intra-volcanic sample variability. However, we do find a significant difference in Hg concentration of ash among volcanic sources, which indicates that volcanoes may emit comparatively high or low quantities of Hg. We combine our Hg findings with total mass estimates of ashfall deposits to calculate minimum, first-order Hg emissions of 8.23 t Hg for Mount Spurr (1992), 1.25 t Hg for Redoubt Volcano (2009), and 0.16 t Hg for Augustine Volcano (2006). In particular, we find that Mount Spurr is a high Hg emitting volcano, and that its 1992 particulate Hg emissions likely contributed substantially to the global eruptive volcanic Hg budget for that year. Based on our findings, previous approaches that use long-term Hg/SO2 mass ratios to estimate eruptive total Hg under-account for Hg emitted in explosive events, and global volcanogenic Total Hg estimates need revisiting

Self-limiting atmospheric lifetime of environmentally reactive elements in volcanic plumes

The 2018 eruption of Kīlauea, Hawai’i, produced exceptionally high discharge of metal pollutant elements, and an unprecedented opportunity to track them from vent to exposed communities over 200 km downwind. We discovered that magmatic volatility is an important control on the atmospheric behavior of elements, with [volatile elements] decreasing up to 100 times faster after emission than [refractory elements]. The differential deposition disproportionately impacts populated areas closest to the active vents, as the rapidlydeposited volatile elements generally have the highest environmental lability and potential toxicity

Rapid metal pollutant deposition from the volcanic plume of Kīlauea, Hawai’i

AbstractLong-lived basaltic volcanic eruptions are a globally important source of environmentally reactive, volatile metal pollutant elements such as selenium, cadmium and lead. The 2018 eruption of Kīlauea, Hawai’i produced exceptionally high discharge of metal pollutants, and was an unprecedented opportunity to track them from vent to deposition. Here we show, through geochemical sampling of the plume that volatile metal pollutants were depleted in the plume up to 100 times faster than refractory species, such as magnesium and iron. We propose that this rapid wet deposition of complexes containing reactive and potentially toxic volatile metal pollutants may disproportionately impact localised areas close to the vent. We infer that the relationship between volatility and solubility is an important control on the atmospheric behaviour of elements. We suggest that assessment of hazards from volcanic emissions should account for heterogeneous plume depletion of metal pollutants.</jats:p

The International Volcanic Health Hazard Network (IVHHN): reflections on 20 years of progress

Peer reviewed: TrueAcknowledgements: The authors would like to thank all collaborators (both academics and practitioners) who have supported the work of IVHHN over the past 20 years. Without such support, IVHHN would not be the organization that it is today. We also thank the Leverhulme Trust for funding a Research Interchange Grant in 2003, which supported the inception of IVHHN. Our thanks to Liz Westby, Katie Mulliken and two reviewers for their insightful reviews. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government

The International Volcanic Health Hazard Network (IVHHN): reflections on 20 years of progress

The International Volcanic Health Hazard Network (IVHHN; www.ivhhn.org) is an interdisciplinary organization which coordinates research and provides advice on volcanic health hazards and impacts.The field of research on the human health hazards and impacts of volcanic eruptions dates to 1980 with the eruption of Mount St. Helens (Baxter et al., 1981; Buist and Bernstein, 1986; Horwell and Baxter, 2006). The principal concerns revolved around the respirable crystalline silica (RCS) content of volcanic ash, which blanketed a vast swath of the north-western United States, and its potential to cause the fibrotic lung disease silicosis in exposed communities. A well-known occupational hazard for mine and quarry workers exposed to natural mineral dusts, the consequences of 24-h exposure to the airborne ash, for children and the public, in general, required urgent appraisal to allay panic amongst the million people living and working in the affected areas.State and federal agencies were immediately mobilised to respond to the emergency and the later recovery phases of the disaster, in collaboration with academic and other research groups. The public health component of this vast undertaking involved many disciplines and was summarised in a volume edited by Buist and Bernstein (1986). The research at Mount St. Helens was reassuring in resolving the health concerns at the time, but also highlighted the future need to systematically identify and quantify the hazards and provide informed advice on mitigation measures because the mineralogy of volcanic ash, along with its respiratory hazard, varies with every eruption.The Mount St. Helens response was, without doubt, enabled by the financial resources and expertise in the United States. Indeed, the next eruptions to receive a concerted (or any) health response were related to other high-income countries: Sakurajima volcano, Japan, starting in the 1980s (reviewed by Hillman et al., 2012), and Soufrière Hills volcano, Montserrat, a British Overseas Territory, in the late 1990s (reviewed by Baxter et al., 2014), where RCS concentrations were substantially higher than at Mount St. Helens, presenting a significant silicosis risk for the islanders that required special mitigation measures (Hincks et al., 2006). The UK government had the legal responsibility for the health and safety of the Montserrat population and funded the health research as well as supporting the island’s disaster management. Apart from these events, individual research studies have been conducted at various volcanoes (reviewed in Horwell and Baxter, 2006; Mueller et al., 2020b; Stewart et al., 2022), but coordinated, interdisciplinary health responses have been rare, leaving communities both proximal and distal to volcanically active areas uninformed about exposure to airborne gas and ash emissions - and other volcanic hazards - and at risk.Interdisciplinary responses that inform hazard assessments are essential because critical public health decisions need to be made early in the exposure timeframe. Rapid geochemical and toxicological assessments can identify hazardous characteristics of volcanic ash (Horwell et al., 2013) that could otherwise take years or decades to manifest as respiratory or other chronic diseases. Immediate exposure assessment through ambient air quality monitoring of particles and gases can provide essential data for epidemiological and clinical studies, linking acute symptoms and future diseases to the correct exposure source (Mueller et al., 2020b; Whitty et al., 2020). Personal monitoring of high-risk individuals, such as outdoor workers, can justify implementation of mitigating measures to reduce exposures. Yet, often, experts in these different areas of environmental health sciences are not working together routinely prior to an eruption. Additionally, these experts may be inexperienced in the collection and analysis of volcanic materials

Physicochemical hazard assessment of ash and dome rock from the 2021 eruption of La Soufrière, St Vincent, for the assessment of respiratory health impacts and water contamination

La Soufrière, St Vincent, began an extrusive eruption on 27 December 2020. The lava dome was destroyed, along with much of the pre-existing 1979 dome, in explosive eruptions from 9 to 22 April 2021. Lava domes generate crystalline silica – inhalation of which can cause silicosis in occupational settings – which can become hazardous when dome material is incorporated into volcanic ash. La Soufrière ash (17 samples) was analysed, according to IVHHN protocols, to rapidly quantify crystalline silica and test for other health-relevant properties. The basaltic andesitic ash contained,5 wt% crystalline silica, which agrees with previous analyses of ash of similar compositions and mirrors the low quantities mea-sured in dome samples (2 area %). It contained substantial inhalable material (7–21 vol%,10 µm). Few fibre-like particles were observed, reducing concern about particle shape. Leaching assays found low concentrations of potentially toxic elements, which indicates low potential to impact health, contaminate drinking-water sources or harm grazing animals through ingestion. Collectively, these data indicate that the primary health concern from this eruption was the potential for fine-grained ash to increase ambient particulate matter, an environmental risk factor for respiratory and cardiovascular morbidity and mortality. Precautionary measures were advised to minimize exposure.</p