Increased respiratory morbidity associated with exposure to a mature volcanic plume from a large Icelandic fissure eruption

Hanne Krage Carlsen,Thor Aspelund,Haraldur Briem,Melissa Anne Pfeffer,Ragnhildur Gudrun Finnbjornsdottir,Thorarinn Gislason,Peter J Baxter,Throstur Thorsteinsson,Unnur Valdimarsdóttir,Francesca Dominici,Evgenia Ilyinskaya,Sara Barsotti,Thorolfur Gudnason,Thorsteinn Jóhannsson,Anja Schmidt

doi:10.1038/s41467-021-22432-5

Abstract

The 2014–15 Holuhraun eruption in Iceland was the largest fissure eruption in over 200 years, emitting prodigious amounts of gas and particulate matter into the troposphere. Reykjavík, the capital area of Iceland (250 km from eruption site) was exposed to air pollution events from advection of (i) a relatively young and chemically primitive volcanic plume with a high sulphur dioxide gas (SO2) to sulphate PM (SO42−) ratio, and (ii) an older and chemically mature volcanic plume with a low SO2/SO42− ratio. Whereas the advection and air pollution caused by the primitive plume were successfully forecast and forewarned in public advisories, the mature plume was not. Here, we show that exposure to the mature plume is associated with an increase in register-measured health care utilisation for respiratory disease by 23% (95% CI 19.7–27.4%) and for asthma medication dispensing by 19.3% (95% CI 9.6–29.1%). Absence of public advisories is associated with increases in visits to primary care medical doctors and to the hospital emergency department. We recommend that operational response to volcanic air pollution considers both primitive and mature types of plumes.

Highlights

The 2014–15 Holuhraun eruption in Iceland was the largest fissure eruption in over 200 years, emitting prodigious amounts of gas and particulate matter into the troposphere
Over 800 million people are estimated to live within 100 km from active volcanoes (2011 data)[1], a distance within which they are potentially exposed to air pollution from volcanic gas and aerosol particulate matter (PM) emissions
After emission into the atmosphere, SO2 gas transforms into sulphate PM (SO42−) at a rate that depends on multiple parameters including ambient temperature and humidity, solar flux, and interactions with other PM3

Summary

Introduction

The 2014–15 Holuhraun eruption in Iceland was the largest fissure eruption in over 200 years, emitting prodigious amounts of gas and particulate matter into the troposphere. In this study we assess the register-based health care utilisation after exposure to the non-forecast and nonmonitored chemically mature volcanic plume (low SO2/SO42− ratio). This study provides the most robust evidence to-date that ground-level exposure to a chemically mature volcanic plume leads to increased health care utilisation.

Results

Conclusion