Fate Formation And Transport Of Indoor PM EPA04 T2.2 Larry Tavlarides & Meera Sidheswaren, Syracuse University and Phil Hopke & Xi Chen, Clarkson University 1

Task 2.2 Introduction Epidemiological studies link “reactive” fine particles to human health hazards including mortality (Pope and Dockery, 1996; USEP, 1997), especially those generated indoors (Long et al., 2001) Important to know chemistry of particle formation, the nature of VSVOC’s formed, and the fate of VSVOC’s due to interactions with room surfaces and secondary organic aerosols (SOA’s) Terpene and terpene-alcohol ozone reaction systems will be studied as these compounds exist in room fresheners, perfumes and laundry softeners. 2

Formation of SOA Initial Models

Formation of SOA More Complete Models – Odum et al., ES&T 1997; Liang et al ES&T 1997

Objectives: Task 2.2.4 Ozone Reactions of Linalool and Adsorption of VOC and SVOC By-Products on Surfaces and SOA Understand the kinetic mechanism which describes the gas phase reaction of linalool with ozone. These studies will be performed in the 150 ft3 stainless steel chamber. Determine the adsorption and desorption behavior of VSVOCs on building surfaces. These studies will also be performed in the same chamber with all walls exchanged with building materials. Characterize the growth of SOAs due to the adsorption of VSVOCs and develop size distribution and growth dynamic models. 5

Reaction Pathway Study Branch 1 Branch 2 6

Reaction Pathway Study: Branch 1

Reaction Pathway Study: Branch 2

Mass Spectra of Some Products 2-Ethenyl-5-methyl-5-hydroxytetrahydrofuran 2-(3-H)-Furanone-5-ethenyldihydro-5-methyl- 2-Furancarboxylicacidtetraydro-1-methyl-5-oxo 2-Hydoxy2,3-dimethylsuccinic acid 9

Particle Phase Analysis Similar to the analysis by Leungsakul et al., 2005 10

Experiments: Conducted at 22-24 °C Sl.no Linalool Concentration, ppb Ozone Concentration, ppb Humidity Mode of Operation 1 492 ± 7 ~502 22-25% Batch 2 512 ± 10 ~298 3 108 ± 5 ~100 Continuous (RT: 10mins) 11

Particle Size Distribution 12

Particle Size Distribution 13

Particle Size Distribution Linalool Concentration: ~100 ppb; Ozone Concentration: ~100 ppb Time of Sampling : Continuous. Time Scale: Reading 1: 15mins Reading 19: 285mins 14

Yield Model Linalool Concentration: 500ppb, Ozone Concentration: 500ppb, Humidity: 25% (T. Hoffmann, J. Odum, et al., 1997) 15

Batch Injection of Linalool in Mid-size Chamber 16

T2.2.4: Results The 150 ft3 chamber has been built, commissioned and is fully functional. Diffusion cell for continuous linalool injection is being fabricated. Gas and particle phase analyses using GC-MS technique have been developed. Initial qualitative analyses of products for preliminary estimation of the reaction pathway has been completed in the 100 L chamber. Two major products of linalool ozone reaction have been synthesized 17

T2.2.4: Future Work Quantification of significant linalool ozone products Proposed experiments for the particle size distribution and yield of SOA’s in the 150 ft3 chamber will be executed. Obtain sorption data for suggested building materials to quantify particle adsorption on surfaces. Obtain parameters for secondary organic aerosol growth models and describe the dynamics of aerosol formation. 18

Formation of Indoor Particles a-Pinene and Ozone There have been many studies of the a-Pinene and Ozone system. However, many of these studies have been performed to provide critical reaction rate constants for chemical transport models. Thus, the reactions with ozone need to be separated from the reactions with hydroxyl radical. For example, Presto and Donahue (ES&T 2006) summarize much of the prior data along with their chamber results where a hydroxyl radical scavenger like butanol has been added to the chamber

Formation of SOA a-Pinene and Ozone

Formation of Indoor Particles Current Progress Much of this year has been used to develop and test the experimental systems: Chamber Ozone Generation Reactive VOC Generator Particle Measurement System Particle Composition Measurements

Formation of SOA Experiment 1 Experiment 2 a-pinene (ppb) 59.6±4.8 a-Pinene and Ozone Experiment 1 Experiment 2 a-pinene (ppb) 59.6±4.8 67.6±9.6 Ozone (ppb) 45.8±0.2 33.8±0.7 Temperature (oC) 21-23 20-21 Relative humidity 28-36% 23-32% Air exchange rate (h-1) 0.53

Formation of SOA a-Pinene and Ozone – Experiment 1

Formation of SOA a-Pinene and Ozone - Experiment 2

Formation of SOA a-Pinene and Ozone

Figure from Fan et al., ES&T 2003. Formation of SOA a-Pinene and Ozone Figure from Fan et al., ES&T 2003.

Formation of Indoor Particles Current Progress Thus, initial results appear comparable with prior flow through chamber results. We need to extend the time to longer periods to examine steady-state behavior. We need to measure ROS concentrations resulting from the new particle formation. In other studies, we have been examining the nature of the reaction products for a-pinene and ozone.

Formation of Indoor Particles Future Work We will continue the work with a-pinene and ozone to obtain the D(Particle Formation) v D(Hydrocarbon Reacted) to provide results without the OH scavenger to provide curves relevant to indoor air modeling. To explore other possible reactive VOCs, we have started to explore the presence of compounds in a series of commercial air fresheners Analysis of a number of commercial air freshener products by GC/MS.

Possible SOA Precursors Found Limonene Terpineol Methyl-cinnamaldehyde Eugenol Rose Oxide Linalyl butyrate Beta-Ionone Linalyl anthranilate a-bergamotene a-Isomethylionone Hexenylsalicylate Muurolene Cis-verbenol

Results Many of these compounds have more than one double bond. These compounds behave differently from the single double bond compounds. As an example, some chamber studies have been made on terpineol

Time-dependent growth curves and final growth curve do not overlap; Formation of SOA Terpinolene and Ozone Time-dependent growth curves and final growth curve do not overlap; time-dependent growth curves show the contribution of the secondary reactions

Results These time-dependent growth curves for terpinolene ozonolysis cannot be fit with Odum equation, confirming that this model is only valid when the data represent final SOA growth. We will need to consider further how best to model the multiple stage reaction systems that the multiply double bonded compounds represent. We need to decide what species to pursue following the completion of the a-pinene-ozone work Terpineol Others?

Discussion and Questions Suggestions?

Formation of SOA a-Pinene and Ozone

Time series of ozone concentration in the chamber Formation of SOA a-Pinene and Ozone Time series of ozone concentration in the chamber

Formation of SOA a-Pinene and Ozone Time series of a-pinene concentrations from the diffusion cell for three different diffusion lengths

Characterization of ROS Species

Characterization of ROS Species (Contd.) a-Isomethylionone Hexenylsalicylate Muurolene Cis-verbenol a-bergamotene Linalyl butyrate

Experimental Set-up Experimental Apparatus Analysis Techniques 100L / 4274.5L stainless steel chamber Injection ports to inject linalool API 400 Ozone generator Dynacalibrator/Diffusion cell for Linalool generation Analysis Techniques API 440 Ozone Analyzer ppB RAE for VOC monitoring Tenax sorbents Samples pulled out through an ozone trap using handheld socket pump (ozone trap made of potassium iodide) PFPH coated Tanex for estimation of lower aldehydes (S.A. Hang Ho, J. Z. Hu, 2004) 39

Experimental Set-up (Contd.) Analysis Techniques ATD-GC/MS ATD: Perkin Elmer Turbomatrix 300 (Sorption Temperature @ 210 oC) GC-MS: Thermoelectron (Trace GC Ultra/DSQ) GC Column: Restek 5MS Temperature of Operation: Ramp to 200 C(@ 25oC/min) and holdup for 10 mins Particle Collection TSI 3086 Nano-Aerosol Sampler (Sampling size range: 2nm-100nm) Teflon Filter/Membrane Filter:>200nm Analysis using GC/MS after extracting particles with methanol using overnight Soxhlet Extraction