Bernadette M. Longo

Cardiorespiratory health effects associated with sulphurous volcanic air pollution

OBJECTIVE To investigate cardiorespiratory health effects associated with chronic exposure to volcanogenic sulphur dioxide (SO2) and fine sulphate particle (< or = 0.3 microm) air pollution emitted from Kilauea Volcano, Hawaii. STUDY DESIGN Environmental-epidemiological cross-sectional study. METHODS An air study was conducted to measure exposure levels in the downwind area, and to confirm non-exposure in a reference area. Cross-sectional health data were collected from 335 adults, > or = 20 years of age, who had resided for > or = 7 years in the study areas. Prevalence was estimated for cardiorespiratory signs, and self-reported symptoms and diseases. Logistic regression analysis estimated effect measures between exposed and unexposed groups considering potential confounding including age, gender, race, smoking, dust and body mass index (BMI). Students t-tests compared mean differences in blood pressure (BP), pulse and respiratory rates. RESULTS There were statistically significant positive associations between chronic exposure and increased prevalence of cough, phlegm, rhinorrhoea, sore/dry throat, sinus congestion, wheezing, eye irritation and bronchitis. The magnitude of the associations differed according to SO2 and fine sulphate particulate exposure. Group analyses found no differences in pulse rate or BP; however, significantly faster mean pulse rates were detected in exposed non-medicated, non-smoking participants with BMI <25, and in participants aged > or = 65 years. Higher mean systolic BP was found in exposed participants with BMI <25. CONCLUSIONS Long-term residency in active degassing volcanic areas may have an adverse effect on cardiorespiratory health in adults. Further study at Kilauea is recommended, and the authors encourage investigations in communities near active volcanoes worldwide. Public health interventions of community education, and smoking prevention and cessation are suggested.

Acute Bronchitis and Volcanic Air Pollution: A Community-Based Cohort Study at Kilauea Volcano, Hawai`i, USA

Eruption at Kilauea Volcano, Hawai`i, has continued since 1983, emitting sulfurous air pollution into nearby communities. The purpose of this cohort study was to estimate the relative risk (RR) of acute bronchitis over a period from January 2004 to December 2006 in communities exposed to the volcanic air pollution. A community-based case review was conducted using medical records from clinics and emergency rooms in exposed and unexposed study areas. Initial visits by local residents for diagnosed acute bronchitis were clinically reviewed. The cumulative incidence rate for the 3-yr period was 117.74 per 1000 in unexposed communities and 184.63 per 1000 in exposed communities. RR estimates were standardized for age and gender, revealing an elevated cumulative incidence ratio (CIR) of 1.57 (95% CI = 1.36–1.81) for acute bronchitis in the exposed communities. Highest risk [CIR: 6.56 (95% CI = 3.16–13.6)] was observed in children aged 0–14 yr who resided in the exposed communities. Exposed middle-aged females aged 45–64 yr had double the risk for acute bronchitis than their unexposed counterparts. These findings suggest that communities continuously exposed to sulfurous volcanic air pollution may have a higher risk of acute bronchitis across the life span.

The Kilauea Volcano Adult Health Study

Background: Millions of people reside near active volcanoes, yet data are limited on effects to human health. The Kilauea Volcano is the largest point source for sulfur dioxide in the United States, releasing air pollution on nearby communities since 1983. Objective: The objectives of this study were to provide the first population-based epidemiological estimates and qualitative descriptions of cardiorespiratory health effects associated with volcanic air pollution. Methods: An environmental-epidemiological design was used. Exposure levels of Kilaueas air pollutants were determined by environmental sampling. Prevalence estimates of cardiorespiratory health effects in adults were measured (N = 335) and compared between an exposed and nonexposed reference community. Descriptions of the human-environment interaction with the long-standing eruption were recorded from informants in the natural setting. Results: Ambient and indoor concentrations of volcanic air pollution were above the World Health Organizations recommended exposure levels. There were statistically significant increased odds associated with exposure for self-reported cough, phlegm, rhinorrhea, sore and dry throat, sinus congestion, wheezing, eye irritation, and diagnosed bronchitis. Thirty-five percent of the informants perceived that their health was affected by the eruption, mainly current and former smokers and those with chronic respiratory disease. Discussion: Hypotheses were supported regarding particulate air pollution and the association with adverse cardiovascular functioning. This emerging environmental health issue is under continuing investigation.

SO2 and fine aerosol dispersion from the Kilauea plume, Kau district, Hawaii, USA

Proximal ground-level assessment of sulfur dioxide gas and fine aerosol in the volcanic gas plume downwind from Kilauea volcano indicates high levels of both species. Fine aerosol and SO 2 data were collected in the Kau district, 37-74 km downwind from the eruption, and at a nonexposed control site in Hawi, Hawaii. Typical trade winds and effusive eruption occurred during sampling in August-September 2003. Ambient SO 2 concentrations, measured with diffusion tubes, ranged from 6 to 34 ppbv and correlated negatively with altitude. In contrast, fine aerosol (≤0.3 μm size) concentrations, measured with a cascade impactor, ranged from 0.61 to 11.82 μg/m 3 and correlated positively with altitude. We attribute decrease of SO 2 with altitude to rapid oxidation as diurnal wind patterns blow the plume from oceanic terrain landward to more abundant oxidation sources. Aerosol increase with altitude likely reflects emission of H 2 SO 4 from Kilauea, supplemented by oxidation of SO 2 in atmospheric hydrosols. Kau residents are exposed to volcanogenic pollutants at concentrations that warrant concern for adverse health effects.

Adverse Health Effects Associated with Increased Activity at Kīlauea Volcano: A Repeated Population-Based Survey

Eruptive activity at the Kīlauea volcano (Hawai`i, USA) has increased since 2008 resulting in volcanic air pollution (vog) at levels exceeding the national air quality standard for sulfur dioxide. Previous investigations during lower vog levels found adverse cardiorespiratory effects in the residents. The purpose of this 2012 survey was to reassess and compare the impact of the increased volcanic activity on population health. Prevalence of cardiorespiratory signs, symptoms, and diseases was estimated in vog exposed and unexposed communities, and descriptions of perceived health and environmental effects were collected door-to-door. Vog exposure was significantly associated with increased odds of self-reported cough, phlegm, rhinorrhea, sore/dry throat, shortness of breath, sinus congestion, continual wheezing, eye and skin irritation, and diagnosed hypertension. Field measurements identified significantly higher average systolic and diastolic blood pressures () and lower blood oxygen saturation (). Half of the participants perceived that Kīlauea’s intensified eruption had negatively affected their health with reports of financial impacts from degradation of agriculture and livestock. Relatively stronger magnitudes of health effects were associated with the higher exposure to vog. Public concerns remain about attributed effects of the ongoing eruption. Enhanced public health efforts are recommended at Kīlauea and other degassing volcanoes worldwide.