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Effects of Volcanic SO 2 on Pulmonary Function. Reid Hoshide E Fernandez, J Orr, B Brooks, A Grandinetti , P Holck , EK Tam. Pu’u O’o Cone, 1983. Introduction. Major emissions are from Pu’u O’o vent and some from Kilauea Crater.
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Effects of Volcanic SO2 on Pulmonary Function Reid Hoshide E Fernandez, J Orr, B Brooks, A Grandinetti, P Holck, EK Tam Pu’u O’o Cone, 1983
Introduction • Major emissions are from Pu’uO’o vent and some from Kilauea Crater. • These volcanic emissions are comprised mostly of SO2, CO2, and H2O vapor. • Recent SO2 emissions can range from 300 tons per day (at pause) to 6000 tons when the volcano is active.
Dispersal of SO2 • Heavily dependent on wind patterns: • Predominantly tradewinds (from the northeast) from May to October. • More frequent periods of “Kona winds” from the south from November to April.
Previous research • In animal studies, high concentrations of SO2 shows airway inflammation and hyperresponsiveness1. • Studies on mild asthmatics that were introduced to SO2 levels of 500 ppb increased airway resistance when delivered in cold, dry air (4 degrees C and relative humidity 40%) while exercising2. • Epidemiological studies showed that sulfates increased bronchitis, chronic cough, and chest illness from man-made, fossil fuel sources3. 1Bethel RA, Erle DJ, Epstein J, Sheppard D, Nadel JA, Boushey HA. Effect of exercise rate and route of inhalation on sulfur-dioxide- induced bronchoconstriction in asthmatic subjects. Am Rev RespirDis 1983;128(4):592-6. 2Linn WS, Venet TG, Shamoo DA, Valencia LM, Anzar UT, Spier CE, et al. Respiratory effects of sulfur dioxide in heavily exercising asthmatics. A dose-response study. Am Rev RespirDis 1983;127(3):278-83. 3Dockery DW, Speizer FE, Stram DO, Ware JH, Spengler JD, Ferris BG. Effects of inhalable particles on respiratory health of children. Am Rev RespirDis 1989;139(3):587-94.
Volcano Village • 2,231 Residents (2000 census). • 4 miles north of Kilauea. 8 miles northeast of Pu’uO’o vent. • Can be exposed to SO2 levels as high as 2000 ppb (depends strongly on wind direction, duration, and speed). • (EPA’s regulation: 24 hour average from manmade sources should not exceed 140 ppb SO2)
Questions How does ambient SO2 concentration affect the pulmonary function of adults? What are the exposures in Volcano Village? What are confounding factors in the population of Volcano Village?
Methods • Study period: July 2006 – February 2007. • Concurrent measurement of ambient SO2 concentration with the measurement of pulmonary function. • Convenience study participants recruited according to protocol approved by the UH Committee on Human Studies.
Measuring SO2 SO2 was measured every 5 minutes in Volcano Village using a Interscan 4240-DSP monitor (Chatsworth, CA). Maximum, average, and cumulative SO2 concentrations were calculated for periods of 1, 24, and 72 hours before pulmonary function testing.
Participants Inclusion: Any adults whom lived in Volcano Village. Exclusion: Family or personal history of diabetes or heart disease, current smokers, current pregnancy. Total participants: 18
Measuring Pulmonary Function • EasyOnespirometers (ndd, Andover, MA) used to determine Forced Expiratory Volume in one second (FEV1) and the Forced Vital Capacity (FVC). • 6-8 spirometer measurements per subject per visit. • Best FEV1 and FVC were selected based on American Thoracic Society criteria for reproducibility and acceptability.
Statistical Analysis Because there were multiple measures for each subject, the use of the Generalized Estimating Equations model allowed for regression of SO2 concentration with pulmonary function tests amongst all measurements. Regression was done via SAS 9.1 (Cary, NC).
Table 1: Measures of SO2 Concentration Prior to PFT Test Period Recall: (EPA’s regulation: 24 hour average from manmade sources should not exceed 140 ppb SO2)
FEV1 *Exposure prior to pulmonary function tests
FEV1 to FVC ratio *Exposure prior to pulmonary function tests
Conclusion • FEV1 decreased significantly with increases in SO2 up to a maximum concentration of 450 ppb. • FEV1/FVC did not decrease statistically significantly in this exposure range. • This may suggest upper airway changes or more shallow breathing with less evidence of lower airway obstruction.
Future Aims • Additional monitoring of SO2 at more sites within Volcano Village during Kona wind seasons. • Increase the power of the study • increase sample size • repeated measures (longitudinal) • Study children • Fewer chronic conditions • Potentially more susceptible due to their larger surface to volume ratio than adults • Shorter • More active outdoors • Volcano School of Arts & Sciences (K-8; 140 students), is in the exposure area
Implications for Public Health • On high vog days: • Stay indoors • Use air conditioning • Moist handkerchief
Special Thanks…. • Dr. Peter Holck • Dr. John Grove • Dr. Andrew Grandinetti • AIR Project Research Team (Ed Fernandez, Jennifer Orr, Marianne Yoshida, Oana Bollt, Beau Dylan Fern, Jeff Sutton, Tamar Elias) Supported by: Centers for Disease Control, Hawaii Department of Health, American Lung Association of Hawaii, Leahi Fund, Hawaii Community Foundation.
Effects of Volcanic SO2 on Pulmonary Function Pu’u O’o Cone, 1983 Reid Hoshide E Fernandez, J Orr, B Brooks, A Grandinetti, P Holck, EK Tam