Spatially modelling the risk areas of chronic exposure to hydrothermal volcanic emissions using lichens

Filipe Bernardo; Pedro Pinho; Paula Matos; Fátima Viveiros; Cristina Branquinho; Armindo Rodrigues; Patrícia Garcia

doi:10.1016/j.scitotenv.2019.133891

Spatially modelling the risk areas of chronic exposure to hydrothermal volcanic emissions using lichens

Sci Total Environ. 2019 Dec 20:697:133891. doi: 10.1016/j.scitotenv.2019.133891. Epub 2019 Aug 12.

Authors

Filipe Bernardo¹, Pedro Pinho², Paula Matos², Fátima Viveiros³, Cristina Branquinho⁴, Armindo Rodrigues³, Patrícia Garcia⁵

Affiliations

¹ Faculty of Sciences and Technology, University of the Azores, 9501-801 Ponta Delgada, Portugal; Centre for Ecology, Evolution and Environmental Changes, and Azorean Biodiversity Group (cE3c-GBA), University of the Azores, 9501-801 Ponta Delgada, Portugal. Electronic address: filipe.mt.bernardo@uac.pt.
² Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa (cE3c-FC-ULisboa), Edifício C2, 5º piso, Campo Grande, 1749-016 Lisboa, Portugal.
³ Faculty of Sciences and Technology, University of the Azores, 9501-801 Ponta Delgada, Portugal; IVAR, Institute of Volcanology and Risks Assessment, University of the Azores, 9501-801 Ponta Delgada, Portugal.
⁴ Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal; Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa (cE3c-FC-ULisboa), Edifício C2, 5º piso, Campo Grande, 1749-016 Lisboa, Portugal.
⁵ Faculty of Sciences and Technology, University of the Azores, 9501-801 Ponta Delgada, Portugal; Centre for Ecology, Evolution and Environmental Changes, and Azorean Biodiversity Group (cE3c-GBA), University of the Azores, 9501-801 Ponta Delgada, Portugal.

PMID: 32380593
DOI: 10.1016/j.scitotenv.2019.133891

Abstract

Human populations living in volcanically active areas are chronically exposed to volcanogenic air pollution, potentially contributing to long-term adverse health effects. However, mapping chronic exposure is difficult due to low spatial resolution of monitoring data on air pollutants and the need for time integration. To overcome these problems, lichens were tested as ecological indicators of hydrothermal volcanic air pollution, considering their bioaccumulation capacity over time, by transplanting them from a reference area to several sites (n = 39) in a volcanic area. The test was developed at Furnas volcano (Azores, Portugal). A stratified sampling design was followed using previous measurements of soil CO₂ flux at ground level and the distance to the main fumarolic fields. After 6 months of exposure, lichen transplants were analyzed for S isotopic ratio (δ³⁴S), which strongly related with the distance to fumarolic fields on a logarithmic regression, serving as an appropriate hydrothermal exposure biomarker. Considering kriging interpolated δ³⁴S values as tracer of airborne hydrothermal emissions and habitational areas as proxy of ongoing human presence, a map was built relating both information per area unit to spatially model risk areas. It was estimated that 26% of habitational areas in the study area stand at high or very high risk of outdoors chronic exposure to airborne hydrothermal emissions. This methodologic approach to produce chronic exposure risk maps is applicable to other volcanically active and inhabited areas of the world, with time-integration and high spatial resolution, contributing in this way for spatially focusing future human health assessments.

Keywords: Air pollution; Biomonitoring; Chronic exposure; Lichens; S isotopic ratio; Volcanism.

MeSH terms

Air Pollutants / analysis*
Azores
Environmental Exposure / analysis
Environmental Monitoring / methods*
Humans
Lichens / chemistry*
Portugal
Volcanic Eruptions*

Substances

Air Pollutants