PERCH Air Quality Study – PAQS Special thanks to Carl Mohrherr Alan Knowes Staff of OJSES FL-DOH FL-DEP SEARCH Partnership for Environmental Research and Community Health

PERCH Air Quality Study – Phase II Scope: air toxics, ozone, and particulate matter. Identify, compile, and assess existing emissions and ambient air data from US EPA, FL DEP, and private (e.g. SEARCH). Review existing studies (particularly National Air Toxics Assessment and Gulf Coast Ozone Study). Any gaps? Complete a health impacts literature search. Screen for potential health risks due to realized and potential ambient exposures. Design and conduct field pilot study. Phase II Findings Reported at Meetings on 11/3/03 and 12/8/03, and in Quarterly Reports Nov’03 and Feb’04.

Pollutants at OJS and in the Region

Diurnal Characteristics: Averages, Std.Dev. OLF UWF ELY OJS PNS NAS NVR Convective winds Sporadic SO 2 events Bimodal CO and NOy Similar daytime O 3 maxima at all sites Less nighttime O 3 titration at NAS shoreline Trend to higher PM 2.5 mass in southern part

Air Toxics from VOC can samples Halogenated HCs F-114 F-11 F-113 CCl 4 Aromatics Benzene Toluene Ethylbenzene m-xylene p-xylene o-xylene 1,3-butadiene 4-ethyltolene 1,3,5-trimethylbenzene 1,2,4-trimethylbenzene AVG STD AVG STD

VOC Source Apportionment via CMB8

Gasoline related sources were dominant contributors (combined ~ 65 %), followed by primers and enamel, refinery fugitives, biogenics, and diesel exhaust. Trend to higher biogenic contributions during daytime. Trend to higher gasoline contributions during nighttime and early morning. Similarities to air toxics (aromatics). VOC Source Apportionment via CMB8

Transport from Local and Distant Sources Ozone (O 3 ) OJS WAR NAS NVR OLF ELY PNS

Transport from Local and Distant Sources Carbon Monoxide (CO) ELY WAR UWF OJS PNS NAS NVR OLF

Transport from Local and Distant Sources Fine PM Mass (PM 2.5 ) NAS NVR OJS PNS OLFELY

Fine Particle Composition Monitor “PCM” Reactive Gases and PM 2.5 Species Channel 1: NH 3 Na +, K +, NH 4 +, Ca +2 Channel 2: HF, HCl, HONO, HNO 3, SO 2, HCOOH, CH 3 COOH, (COOH) 2 F -, Cl -, NO 3 -, SO 4 =, HCOO -, CH 3 COO -, C 2 O 4 = Channel 3: EC, OC, “SVOC”

PCM Data Quality: Reactive Gases Reactive Gases

PCM Results: Reactive Gases NH 3 systematically lower at daytime ( ppbv) than nighttime ( ppbv). Formic and Acetic track closely, higher during day than night, indicating microbial soil (T) and photochemical atmospheric sources (esp. dry period at end). HNO 3 tracks with O 3, maximum at day, and towards high O 3 (and PM 2.5 ) period at end, pointing to photochemical source.

PCM Results: PM 2.5 Acidity Charge balance shows high acidity towards dry period at end of campaign.

PCM Results: PM 2.5 Mass and Composition Sulfate fraction highest towards end. Uncertainty in Un-ID caused by uncertain EC and OC!

PCM Data Quality: PM 2.5 PM 2.5 Mass and Water-soluble Ions

PCM Data Quality: EC/OC PM 2.5 Elemental and Organic Carbon Also, same punch analyses (precision): % uncertainty (usually <10%)!!

Phase II Findings Period 7/15-8/14 characterized by frequent precipitation. Period has been unseasonably wet for SE-US. Leading to low [O 3 ] and [PM 2.5 ] region-wide. Land-sea breeze circulation most prominent at shore sites. Sea breeze (southerly flow) converging with westerlies on middays. Highest [O 3 ] associated with southerly component flow at all sites. Highest [PM 2.5 ] with continental air mass during dry period at end. OJS predominantly influenced by mobile sources (CO, NOy). Sporadic SO 2 events during morning BL evolution. Gasoline related sources largest contributor to total measured VOC, highest at night and early morning. Biogenic VOC contribute most (8 +-4 %) during daytime. High O 3 and PM 2.5 event associated with highest HNO 3 and LOA. Formic and Acetic track closely, higher during day, indicating microbial soil (T) and photochemical atmospheric sources. NH 3 systematically higher at night, early a.m.  mobile sources? Highest SO 4 = mass fraction and acidity during high PM period. Large (>40%) but uncertain organics fraction, plus highly uncertain EC, due to hidden instabilities in TOT laser intensity and T controls.

Improve EC and OC data quality by reanalysis. Integrate and comprehensively evaluate regional PM 2.5 mass and composition data (incl. FLDEP, ADEM, GAEPD, SEARCH). Characterize air mass history from regionally elevated PM episode i.t.o. transport (back-trajectories) and chemical transformation; apply Lagrange box model, emissions, and STN observations. Identify origin and primary sources (distant but large wild fires?) for regional pollution. Estimate P(O 3 )/OPE and evaluate in conjunction with OM/OC estimates and relative OC fractions evolving at different T, to constrain OC oxidation state. Assess fraction of Secondary Organic Aerosol (SOA) from EC tracer method (OC/EC ratio). Develop selection criteria for primary EC/OC considering measured photochemical products (O 3, HNO 3, NOz/NOy) and primary source indicators (CO, SO 2, NOy and ratios) Phase III Outlook

Secondary organic aerosol (SOA): Organic compounds, some highly oxygenated, residing in the aerosol phase as a function of atmospheric reactions that occur in either gas or particle phases. SOA formation mainly depends on: Emissions & forming potential of precursors aromatics (BTX, aldehydes, carbonyls) terpenes (mono-, sesqui-) other biogenics (aldehydes, alcohols) Presence of other initiating reactants O 3, OH, NO 3, sunlight, acid catalysts Mechanisms (with half hr to few hr yields): Gas-to-particle conversion/partitioning e.g. terpene oxidation Heterogeneous reactions aldehydes via hydration and polymerization, forming hemiacetal/acetal in presence of alcohols Particle-phase reactions acetal formation catalytically accelerated by particle sulfuric acid (Jang and Kamens, ES&T, 2001)

Photochemical Processes Leading to O 3 and PM SOA NOz An Assessment of Tropospheric Ozone Pollution, A North American Perspective, NARSTO, National Acad. Press, 2000.

Atlanta JST Griffin downwind Elevated regional O 3 background reflected in regression’s intercept: higher in Aug 99! At JST higher intercept and slope during Aug ’99 (OPE= 4 vs 3): more efficient P(O 3 ). OPE in air mass arriving at Griffin is likely larger given by upper and lower limits. Lower limit assumes 1 st order loss of HNO 3 due to surface deposition at k ≈ 0.22 h -1. Air mass transitions from VOC-limited to NOx-limited regime due to Biogenic HC. High photochemical activity P(O 3 ) allows for high P(SOA): rural/urban gradient. Photochemical Activity Source – Receptor Considerations: O 3 /NOz as “OPE”

OPE Considerations for Pensacola 2003 Crude midday OPE is very similar for both sites, indicating moderate OPE. Intercept indicating relatively low background O 3 level. A much more refined analysis is required for true OPE. High PM 2.5 /O 3 case study: Compare on temporal and spatial basis.