Wintertime Residential Biomass Burning in Las Vegas, Nevada; Marker Components and Apportionment Methods

Steven Brown,Paul Roberts,Taehyoung Lee,Jeffrey Collett

doi:10.3390/atmos7040058

Abstract

We characterized residential biomass burning contributions to fine particle concentrations via multiple methods at Fyfe Elementary School in Las Vegas, Nevada, during January 2008: with levoglucosan on quartz fiber filters; with water soluble potassium (K+) measured using a particle-into-liquid system with ion chromatography (PILS-IC); and with the fragment C2H4O2+ from an Aerodyne High Resolution Aerosol Mass Spectrometer (HR-AMS). A Magee Scientific Aethalometer was also used to determine aerosol absorption at the UV (370 nm) and black carbon (BC, 880 nm) channels, where UV-BC difference is indicative of biomass burning (BB). Levoglucosan and AMS C2H4O2+ measurements were strongly correlated (r2 = 0.92); K+ correlated well with C2H4O2+ (r2 = 0.86) during the evening but not during other times. While K+ may be an indicator of BB, it is not necessarily a unique tracer, as non-BB sources appear to contribute significantly to K+ and can change from day to day. Low correlation was seen between UV-BC difference and other indicators, possibly because of an overwhelming influence of freeway emissions on BC concentrations. Given the sampling location—next to a twelve-lane freeway—urban-scale biomass burning was found to be a surprisingly large source of aerosol: overnight BB organic aerosol contributed between 26% and 33% of the organic aerosol mass.

Highlights

Understanding the impact of residential biomass burning on aerosol concentrations in urban areas is of particular interest, since emissions are potentially controllable through burn-prevention or fireplace change-out programs [1,2] and because residential biomass burning can lead to high concentrations during the evening and overnight, when emissions are trapped in a shallow boundary layer [3,4]
K+ correlated poorly with both black carbon (BC) and UV-BC difference. These results suggest that K+ and UV-BC difference are only modestly good indicators of biomass burning in Las Vegas next to a roadway, probably at least in part because there are other sources of K+ and BC at the monitoring site
Urban-scale biomass burning was found to be a surprising source of aerosol at Fyfe Elementary

Summary

Introduction

Understanding the impact of residential biomass burning on aerosol concentrations in urban areas is of particular interest, since emissions are potentially controllable through burn-prevention or fireplace change-out programs [1,2] and because residential biomass burning can lead to high concentrations during the evening and overnight, when emissions are trapped in a shallow boundary layer [3,4]. These short, high-concentration events can have acute health impacts [5,6], and specific health effects have been associated with inhaling biomass burning. Biomass burning emissions include not just black carbon (BC) and organic matter (OM), and carcinogens such as benzene and polycyclic aromatic hydrocarbons (PAHs) [11]

Methods

Results

Conclusion