# APPENDIX D First Reno Pilot Study

Section 211(B) Tier 2 High-End Exposure Screening Study Of Baseline and Oxygenated Gasoline – Pilot Study

Final Report

Prepared for

AMERICAN PETROLEUM INSTITUTE

1220 L Street Washington, DC 20005-4070

Prepared by

Barbara Zielinska, John Sagebiel, Eric Fujita and Dave Campbell

Desert Research Institute 2215 Raggio Pkwy.

Reno, NV 89512

Jake McDonald Lovelace Respiratory Research Institute Inhalation Toxicology Laboratory

P.O. Box 5890 Albuquerque, NM 87185

Tomas J.Kelly and Darrell W. Joseph

Battelle 505 King Avenue, Columbus, Ohio 43201

June 13, 2002

## ii

## ACKNOWLEDGMENT

This work was supported by the American Pe troleum Institute (API) and was conducted

in coordination with the U.S. Environmental Pr otection Agency. We gratefully acknowledge the technical support provided by Dr. Will Ollison of the API and Dr. Ted Johnson of TRJ Environmental during the pilot study.

iii

## TABLE OF CONTENTS

Acknowledgment ................................................................................................................. ........... ii

List of Tables ................................................................................................................. ................ iii List of Figures................................................................................................................ ................ iv

1. INTRODUCTION ................................................................................................................... 1-1

1.1 Measurement Methods ......................................................................................... 1-1

1.2 Description of Microenvironm ents and Sampling Procedures ............................1-2

2. RESULTS

............................................................................................................................... . 2-1

2.1 Continuous Instruments ....................................................................................... 2-1

2.2 Integrated Samples ............................................................................................... 2-2

2.3 Solid Phase Microextraction (SPME) .................................................................. 2-5

2.4 Biological Samples .............................................................................................. 2-6

2.4.1 Breath VOC Concentrations .................................................................... 2-6

2.4.2 Urine VOC Concentrations ...................................................................... 2-8

2.5 Results of Additional Refueling Experiment (June 4, 2002, Reno) ..................2-10

2.5.1 MS200 and Canister Results .................................................................. 2-11

2.5.2 Breath Sample Results ........................................................................... 2-11

2.5.3 Analysis of Urinary VOC Concentrations ............................................. 2-12

3. RECOMMENDATIONS ......................................................................................................... 3-1

3.1 Exposure Measurements ...................................................................................... 3-1

3.2 Recommendations for Measurements of VOC in Breath ....................................3-2

3.3 Recommendations for Measurement of VOC in Urine ....................................... 3-3

4. REFERENCES ........................................................................................................................ 4-1

iv

## LIST OF TABLES

Table 1.1 API S211 (b) Exposur e Study-Reno Pilot Study ........................................................ 1-2

Table 2.1 Canister and Te nax/Carbotrap Data............................................................................ 2-3 Table 2.2 Comparison of MS 200 with Canisters ........................................................................ 2-4 Table 2.3 Comparison of Formaldehyde Data ............................................................................ 2-4 Table 2.4 Concentrations (ppbv) of vola tile organic compounds in breath and

microe nvironments...................................................................................................... 2-7 Table 2.5 Urinary benzene concentrations in two subjects exposed to three

Microenvironments ................................................................................................... 2-10 Table 2.6 Breath Data (ppbC) .................................................................................................. . 2-13 Table 2.7 Concentrations of Ethanol, MTBE & BTEX in urine samples (ng/L)...................... 2-16 Table 3.1 Recommendation Summary........................................................................................ 3-1

v

## LIST OF FIGURES

Figure 2-1 Concentration Ti me Series, Freeway AM ...........................................................F-1 Figure 2-2 Concentration Time Series, Surface Streets.........................................................F-2 Figure 2-3 Concentration Ti me Series, Freeway PM ............................................................F-3 Figure 2-4 Concentration Time Series, Refueling In-Cabin..................................................F-4 Figure 2-5 Concentration Time Se ries, Refueling out of cabin.............................................F-5 Figure 2-6 Concentration Time Series, Walking Downtown ................................................F-6 Figure 2-7 Concentration Time Series, Underground Garage...............................................F-7 Figure 2-8 Concentration Time Series , Residential Garage Background A..........................F-8 Figure 2-9 oncentration Time Series, Residential Garage Background B.............................F-9 Figure 2-10 Concentration Time Series , Residential Garage Sample C ...............................F-10 Figure 2-11 Concentration Time Series , Residential Garage Sample D ...............................F-11 Figure 2-12 Concentration Time Series , Residential Garage Sample E................................F-12 Figure 2-13 Concentration Time Series , Residential Garage Sample F................................F-13 Figure 2-14 Concentration Time Series , Residential Garage Sample G ...............................F-14 Figure 2-15 Concentration Ti me Series, Generator...............................................................F-15 Figure 2-16 MS200 Raw and Corrected Data .......................................................................F-16 Figure 2-17 MS200 Corrected Data Only .............................................................................F-17 Figure 2-18 Correlation between CO by T15 and by Innova ................................................F-18 Figure 2-19 Correlation between Innova and TEI for total hydrocarbons ............................F-19 Figure 2-20 Innova vs. TEI for total hydro carbons with three ou tliers removed..................F-20 Figure 2-21 Correlation between CO and formaldehyde ......................................................F-21 Figure 2-22 Correlation between DNP H and continuous formaldehyde...............................F-22 Figure 2-23 Pre and post exposure br eath samples during refueling.....................................F-23 Figure 2-24 Pre and post exposure breath samples during in-cabin fueling..........................F-24 Figure 2-25 Pre and post exposure breath samples during walk ...........................................F-25 Figure 2-26 Relationship between full and alveolar breath...................................................F-26 Figure 2-27 The three traces; benzene, toluene and sun of xylenes and ethylbenzene ......................................................................................................F-27 Figure 2-28 Data for BTEX and MTBE................................................................................F-28

vi

## 1. INTRODUCTION

This report summarized the results of a pilot study that was c onducted in Reno, NV, from February 25 through March 1, 2002 as part of a screening study of the high-end exposures to baseline and oxygenated gasoline. The study is being conducted for the American Petroleum Institute pursuant to Sec tion 211(b) of the Clean Ai r Act. The objectives of the pilot study were to evaluate various monitoring methods under realistic field sampling conditions and to determine their suitability for use in the main exposure study to be conducted in Atlanta, Chicago, and Houston during the upcoming summer and winter seasons. We also evaluated biological sampling methods (breath and urine) for their applicability to the final study. In addition to DRI, personnel from Lovelace Re spiratory Research Institute and Battelle participated in the pilot st udy. The refueling experiment wa s repeated on June 4, 2002 to evaluate the response of the portable mass spectrometer, whic h was not available for the refueling experiment during the pilot study. Th is report includes the results of the second refueling experiment.

1.1 Measurement Methods

During the pilot phase of the study, we evaluated the sensitivity, precision, accuracy, selectivity, power requirements, a nd portability of sampling and mon itoring devices to be used in the main study. The evaluations included met hods for continuous measurement of carbon monoxide (CO), methyl tertiary butyl ether (MTBE), formaldehyde (HCHO), benzene, toluene, ethylbenzene, and xylene s (BTEX), with time integration of 1-5 minutes, and time-integrated measurements of ethanol (EtOH), 1,3-butadiene, and acetaldehyde (CH 3 

## CHO). The following continuous analyzers were us ed during the pilot study:

Background CO, Monitor Labs. Research-grade non-dispersive infrared detection for carbon

monoxide. This was maintained in the mobile la b and measured CO during our runs. Property of

DRI.

T15 CO, Langan products. Electrochemical monitor for CO. Qu ite small and portable, but it is temperature dependant. Property of DRI

Photoacoustic Gas Monitor, Innova. A photoacoustic instrument th at uses infrared light to detect CO and total hydrocarbons (calibrated as propane ). In addition, this instrument could provide CO 2 

## and water vapor (relative humidity). Property of Lovelace.

Continuous Formaldehyde Monitor, Battelle. This instrument monitors formaldehyde in a continuous mode via a reaction to a fluorescent sp ecies and detection in a fluorimeter. Property

of Battelle.

Model TVA1000 FID, Thermo Environmental Instruments. This is a flame ionization based instrument for total hydrocarbons on a continuous basis. Sold primarily for leak detection at petrochemical plants. Property of TEI, on loan to DRI for the pilot study only.

MS200, Kore Technologies. An electron impact ionization time-of-flight mass spectrometer was used for the detection of VOC species. Rather than using a GC to separate species, this

1-1

## 1-2 instrument uses software to quantify species by apportionment of their mass fragmentation patterns. Property of DRI.

In addition to the continuous instruments, time-integrated samples were collected in stainless steel canisters and on 2,4-dinitr ophenylhydrazine (DNPH)-imp regnated silica gel cartridges and Tenax/Carbotrap solid adsorbent tr aps. These samples were collected over a onehour exposure period. The DNPH car tridges were sampled with a potassium iodide coated

denuder to remove ozone. The canisters were analyzed by gas chromatography with flame

ionization detection for BTEX , MTBE, 1,3-butadiene, and tota l nonmethane hydrocarbons. The extracts of the DNPH cartridges were an alyzed by HPLC/UV for formaldehyde and acetaldehyde. The Tenax/Carbotrap sa mples were analyzed for EtOH.

We also tested the solid phase microextra ction (SPME) technique during the pilot study for the collection and analysis of BTEX, MT BE, ethanol, formalde hyde, and acetaldehyde. A

100 μ m (poly)dimethylsiloxane (PDMS) fibers and 75 μ m Carboxen/(poly)di methylsiloxane (CAR/PDMS) fibers were used fo r BTEX, MTBE, and ethanol and 65 μ m PDMS/divinylbenzene (DVB) fiber that was impregnated with o-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine hydrochloride (PFBHA) was used fo r carbonyl compound collection. The fibers were exposed in parallel for 15 to 30 min and were analyzed on a gas chromatograph with both FID and photoionization detector (PID ). Some of the fibers were also analyzed by GC/MS.

1.2 Description of Microenvironments and Sampling Procedures

A summary of the samples collected is presented in Table 1-1. This table details the samples that were taken and a brief summary of the conditions at the time of sampling. In addition, the following notes detail the experiment s. For the three driving exposures, we also collected GPS data showing location and time. Unless noted otherwise, each run last one hour. These are presented in the appendix.

In-cabin Freeway (R02022607), Run #1

For the first 15 minutes, the sampling van drove south on US 395 from Parr Boulevard to

south Reno. This was a stretch of high rush hour traffic. The second 15 minutes, the van drove

north from south Reno to Parr Boulevard. This was a stretch of low rush hour traffic. This loop was repeated for the third and fourth 15-minute periods. Data were not collected for the Innova photoacoustic instrument due to a failure of the pump. Only limited, hand logged, data were

available for the TEI FID because of a failure of the internal memory of that instrument. A few data points are missing due to power pr oblems at the beginning of the run.

In-cabin Surface Streets (R02022612), Run #2

For the first 15 minutes, the sampling va n drove within the “urban canyon” loop, consisting of south on Sierra, east on 4th, north on Virginia, west on 5 th 

## . (This made a total of 4

left turns around the Silver Le gacy Hotel/Casino.). The sec ond 15 minutes, the van drove a surface street loop, consisting of going east on 4th to Wells, north on Wells to Oddie, south on Sutro, and west on 4th. The third 15 minutes be gan at 4th, went north on Center, stopped atTable 1-1. API S211(b) Exposure Study - Reno Pilot StudyRun#Test IDDateStartTimeEndTimeMicroenvironmentExposure LevelLocation/ActivityVentilation ConditionR0202260702/26/0207100810In-cabin - freeway395 from Parr to south RenoR02022607a02/26/0207100725higher -stop& goSB 395 from Parr to south RenoR02022607b02/26/0207250740lower - free flowSouth Reno to DRI via 395R02022607c02/26/0207400755higher -stop& goSB 395 from Parr to south Reno1R02022607d02/26/0207550810lower - free flowSouth Reno to DRI via 395D&P-side windows open halfinch, heater on and vent open tooutside, keep temperaturebetween 60 and 65.R0202261202/26/0212001300In-cabin -surface streetsR02022612a02/26/0212001215higher - urban canyonS onSierra, E on 4th, N on Virginia, W on5th (4 left turns around Silver Legacy)R02022612b02/26/0212151230mixed - cross I-80 w/ostopping)From urban canyon loop, go E on 4th toWells, N on Wells to Oddie, S on Sutro, Won 4thR02022612c02/26/0212301245transect across I-80 with10-min stop at bridgeFrom 4th, N on Center, stop at bridge over I80 for 10 minutes, then go back to urbancanyon loop2R02022612d02/26/0212451300higher - urban canyonS on Sierra, E on 4th, N on Virginia, W on5th (4 left turns around Silver Legacy)D&P-side windows open halfinch, heater on and vent open tooutside, keep temperaturebetween 60 and 65.R0202261602/26/0216001700In-cabin - freeway395 from Parr to south RenoR02022616a02/26/0216001615lower - free flowSB 395 from Parr to south RenoR02022616b02/26/0216151630higher -stop & goSouth Reno to DRI via 395R02022616c02/26/0216301645lower - free flowSB 395 from Parr to south Reno3R02022616d02/26/0216451700higher -stop & goSouth Reno to DRI via 395D&P-side windows open halfinch, heater on and vent open tooutside, keep temperaturebetween 60 and 65.R0202270802/27/0208100910Refueling/in-cabinR02022708a02/27/0208100825baselineFrontage Road just south of Gold Ranchwindow open 1 inchR02022708b02/27/0208250840refueling/in cabinGold Ranch Pump #10window open 1 inch, closedoor once at startR02022708c02/27/0208400855refueling/in cabinGoldRanch Pump #10window half open, opened dooronce4R02022708d02/27/0208550910refueling/in cabinGold Ranch Pump #10window half open



## 1-3Run#Test IDDateStartTimeEndTimeMicroenvironmentExposure LevelLocation/ActivityVentilation ConditionR0202271202/27/0212001300Refueling/outsideR02022712a02/27/0212001215baselineTrailer park south of Gold Ranchwindow open 1 inchR02022712b02/27/0212151230refueling/outsideVan at Gold Ranch Pump #10, filled Suburuwith midgrade gas on Pump #9sampling line to pumpR02022712c02/27/0212301245refueling/outsideVan at Gold Ranch Pump #10, filled Corollawith regular on Pump #9, collected gasolinesamplesampling line to pump5R02022712d02/27/0212451300refueling/outsideVan at Gold Ranch Pump #10, filled Volvowith premium gas on Pump #9, collectedgasoline samplesampling line to pumpR0202281102/28/0211001200Pedestrian walk1 square block around Silver LegacyR02022811a02/28/0211001115Virginia St between 4th and 5th (southbound)R02022811b02/28/02111511304th betweenVirginia and Sierra (westbound)R02022811c02/28/0211301145Sierra between 4th and 5th (northbound)6R02022811d02/28/02114512005th betweenSierra and Virginia (eastbound)R0202281502/28/0215001600Garage undergroundR02022815a02/28/0215001515R02022815b02/28/0215151530R02022815c02/28/02153015457R02022815d02/28/0215451600Survey surrounding area, enter garage andsurvey upper level. Paused for 15 min toallow traffic to build up, then sampled for 1hour.D&P-side windows open 1 inchwith heater on if necessary andvent open while outside ofgaraged, window fully openinside garage, and side doorsopen when stationary.R0203010903/01/0209351340Garage residentialR02030109a03/01/0209351005Background 1R02030109b03/01/0210051035Background 2R02030109c03/01/0211101140Pull car in gar. open kitchen door 1 min andcloseR02030109d03/01/0211401210Kitchen door open.R02030109e03/01/0212101240Kitchen door closed, windows open8R02030109f03/01/0212401310Open garage door and let icar dle for 30 min.open door to kitchen for 1 minute and keepclose for remainder of period.Use house fan located in centerof room to circulate/mix air ingarage and kitchen. Measurecontinuous instruments with 10-min cycle time between garageand kitchen. Sampling linethrough deadbolt hole.



## 1-4

## 1-5R02030109g03/01/0213101340Post Exposure, back car out and close garagedoorRun#Test IDDateStartTimeEndTimeMicroenvironmentExposure LevelLocation/ActivityVentilation ConditionR0203011603/01/0216001630Generator ExhaustR02030116a03/01/0216001605Exhaust downwind (CO ~ 2-3 ppm)R02030116b03/01/0216051610Exhaust upwind (CO peak of 150 ppm)R02030116c03/01/0216101615Exhaust downwind (CO <10 ppm)R02030116d03/01/0216151620Exhaust upwind (CO 10-50 ppm)R02030116e03/01/0216201625Exhaust upwind (CO 20-150 ppm)9R02030116f03/01/0216251630Exhaust downwind (CO <5 ppm)10R0206041006/04/0210101101Refueling/outsideR02060410a10101025Parking west of Gold Ranch- backgroundSampling line outside of vehicleR02060410b10311046At Gold Ranch Pump#10, refueling Volvo (4min) with premium gas on Pump #10Sampling line at breathing highR02060410c10471101At Gold Ranch Pump#10, refueling Corolla(2 min) with regular on Pump#9Sampling line at breathing high

## bridge over I-80 for 10 minutes, then went b ack to the urban canyon loop. The van door was open during the stop at the freeway overpass. Fo r the fourth 15 minutes, the sampling van drove the “urban canyon” loop again, completing another 4 turn s around the Silver Legacy

Hotel/Casino. Data were collected from all in struments , but the MS200 instrument shut down during the run due to vacuum becoming too low.

In-cabin Freeway (R02022616), Run #3

For the first 15 minutes, the sampling van drove south on US 395 from Parr Boulevard to

south Reno. This was a stretch of low rush hour traffic. The second 15 minutes, the van drove

north from south Reno to Parr Boulevard. This was a stretch of high rush hour traffic. This loop was repeated for the third and fourth 15-minut e periods. Data were collected from all instruments, but a few data points are missing due to power problems at the beginning of the run.

In-cabin Refueling (R02022708), Run #4

For both refueling experiments a rural but high volume service station was used. The station is located near a major interstate (I-80), bu t is otherwise in a rural area. The station has 18 fueling pumps and sells between 20,000 and 40,000 gallons of gasoline per day. The mangers indicated they are the largest gasoli ne seller in northern Nevada.

For the first 15 minutes, the sampling van pa rked on the frontage road, near the I-80 freeway, away from the filling station to coll ect a background sample. The goal was to be approximately the same distance from the freeway as we would be at the fueling station. For the next 50 minutes, samples were collected whil e the van was parked at pump number 10, the center pump of the center island. Most equipment worked well, except that the MS200 had vacuum problems and had to be shut down.

Refueling at Pump (R02022712), Run #5

Similarly as with the first experiment, during the first 15 mi nutes, the sampling van parked on the frontage road, near the I-80 freewa y, away from the filling station to collect a background sample. For the next 45 minutes, samples were collected in the breathing zone while the van was parked at pump 10, center of th e center island. Breathing zone was at pump 9 (opposite side of a dual-side pum p), while three cars we re filled with fuel. First was a Subaru that was filled with regular. Next came a Toyota that was filled with mid-grade, and finally was a Volvo filled with super. No formaldehyde data we re collected due to power failure. In addition,

the MS200 was not run due to vacuum problems.

Refueling at Pump, Re peated (R02060410), Run #10

During the first 15 min the vehicle with sampling equipment was park on the quiet parking area, west of Gold Ranch and away fr om the filling station to collect a background sample. Only MS and SPME samples were collect ed. For the next 30 minutes, samples were collected in the breathing zone while the vehi cle with sampling equipment was parked at pump 10, center of the center island. Brea thing zone was either at pump 10 or at pump 9 (opposite side of a dual-side pump), while two cars were filled with fuel. First was a Volvo filled with super,

1-6

## and next came a Toyota Corolla that was filled with regular grade. During 30 min one canister sample and two 15 min SPME samples were coll ected. MS200 was operat ing in a continuous

mode.

Pedestrian Walk (R02022811), Run #6

All the monitoring equipment was placed on two mobile carts with batteries and inverters. For one hour, monitoring was conducte d while the carts were slowly pushed around a large one square block area of central downtown Reno (the Silver Legacy Casino). The block was split roughly into equal time s with approximately 15 minutes spent on each leg of the block.

We started at 4 th 

## and Virginia, went south on Virginia, then west on 5 th 

## to Sierra, then north to 4 th



## and back to the starting point.

Data was collected from all instruments, except that for the first 15 minutes, no formaldehyde data was collected possibly due to a light leak in the fluorescence detector. In addition, the TEI FID did not coll ect data, although it appeared to be on the entire time. The

reason for this failure was never determined.

Underground Public Parking Garage (R02022815), Run#7

The van was parked in an underground parki ng garage for one and a half hours during the period of maximum car departur e. This garage has two underground levels, however the van remained on the upper of these two levels for two r easons. The first is that this level was nearly full while the lower level had only a few vehicles. The second reason is that the traffic ramps in the garage would allow travel from the first underground level down to the second, but from the second level the van could only go up to the surface, not back to the first underground level. The van’s position was relocated seve ral times to try and capture the cold start exhaust from departing vehicles. Data were collected for th e first 15 minutes, followed by a 15 minute zeroing,

and then data collection for the next hour.

Residential Kitchen and Garage without Car (R02030109a,b), Run #8

For both residential exposures a home was used that had an attached two-car garage. The home and the garage share a common wall and there is a door from the garage into the kitchen. For the duration of these experiments a vented 2.5 gallon gasoline storage container was also present in the garage during the sampling period, lo cated in the front center portion of the garage,

closest to the house. The can wa s approximately half-full and th e vent on the gas can was open. The sampling equipment was set up in a residentia l kitchen next to the door of the attached garage. For the first hour, the sampling was done with the garage door closed and no car. Samples were taken alternately for 10 minutes in the kitchen followed by 10 minutes in the garage for one hour.

Residential Kitchen and Garage with Car (R02030109c-g), Run #8

For these experiments the car used was a 1984 Honda Accord with a four-cylinder engine and it is carbureted. The vehicle is normally fu eled with regular gasolin e and annually passes the state smog check with no problems. Prior to pa rking the car in the garage, it was driven approximately 5 miles to warm the engine up. On ce parked in the garage, the air cleaner cover

1-7

## was removed, exposing the inlet of the carburetor and the oil filler cap on the valve cover was removed to allow additional evaporative emissions.

The sampling equipment had the same set up as the background samples. Separate integrated samples were collected in the garage and in the kitchen. The continuous instruments were switched between the garage and the kitchen at 10-minute intervals for 2.5 hours. The sequence of activities was as followed:

Time Activity

1110 1140 Pull car in gar. open kitchen door 1 min and close

1140 1210 Kitchen door open.

1210 1240 Kitchen door closed, windows open

1240 1310 Open garage door and let car idle for 30 min. Open door to kitchen for 1 minute and keep closed for remainder of period.

1310 1340 Post Exposure, back car out and close garage door

Sample probe was on the following sequence:

garage 11:10-11:20

kitchen 11:20-11:30

garage 11:30-11:40

kitchen 11:40-11:50

garage 11:50-12:00

kitchen 12:00-12:10

kitchen 12:10-12:20

garage 12:20-12:30

kitchen 12:30-12:40

garage 12:40-12:50

kitchen 12:50-13:00

garage 13:00-13:10

garage 13:10-13:20

kitchen 13:20-13:30

garage 13:30-13:40

Generator Exhaust (R02030115), Run #9

In the DRI staging lot, the exhaust hose of a gasoline powered elec trical generator was operated near the inlet of the sampling equipment. The genera tor exhaust hose was moved to a different location every 5 minutes. Adjusting its position relative to the instrument inlets; first downwind, then upwind, downwind, upwind, upwind cl oser to exhaust, and finally downwind.

1-8

## 2. RESULTS

The results from this study are presented in four parts: 1) continuous (or semicontinuous) instruments; 2) integrated samples; 3) SPME samples; and 4) biological samples. Where appropriate, comparisons are made between the continuous and the integrated samples. Results from the additional refueling expe riment performed in June 2002 in Reno are

summarized in Section 2.5.

2.1 Continuous Instruments

Figures 2-1 through 2-15 present the time seri es for the continuous analyzers. For the residential garage exposures (2-8 through 2-15) the plots are only 30 minutes, not 60 minutes as for the rest of the plots. This is because of the number of changes th at took place during these exposures. Also, during the residential garage exposures, the sample probe was moved to measure the kitchen area and the garage area as per the schedule listed a bove in the description

of the runs. This accounts for the sudden cha nges in concentration seen in the data.

The MS200 data is not presente d in these time series. When we examined the raw MS data, without background correctio n, we found very high concentr ation levels being reported. The MS200 data appear high during a ll runs, especially compared to the integrated canister data, however, the structure of the data suggests that the MS200 is accurately responding to changes in

ambient concentrations. Additional work was conducte d with this instrument to help explain this

effect. As a result of this work and discussions with the manufacturer (Kore), we have been able

to better understand these data. The data that the MS200 re ports is very dependent on the blank level. In addition, the membrane-based inlet a nd the relatively slow pumping mechanism appear to have the effect of slowing the 2-3 minute reco very time of the instrument, especially when the instrument is challenged with a high concentrati on. To test this we alternatively applied a high

concentration standard and a zero air to th e inlet of the MS200. On the basis of these experiments, we applied a correction that consisted of subtracting a background value consisting of a linearly sloping zero to the data, based on our experiments with the standards. This was difficult in the case of the residential garage where the instrument was switched every 10 minutes between the relatively high concentrations in the garage w ith the much lower levels seen in the kitchen. However, once these backgrounds were subtracted, the MS200 data generally showed agreement (within a factor of 2 at pp b levels) with the canister data, which will be discussed later. We are still working with Kore to develop a pre-concentrator inlet that will allow for a much lower detection limit, however , this will sacrific e time resolution.

An example of the correction applied is in chart 2-16 which shows the original benzene concentration, the zero function applied and the resulting correct ed benzene concentration. The next figure, 2-17 shows the corrected data from this run for benzen e, toluene, and the xylenes. In this chart, it is clear that th e corrected plots track each other in structure, as we expected. The other data sets were similarly corrected and ar e summarized in Table 2-1 with the canister data. The comparison with the canister is quite favorab le, except in the case of benzene at very low

concentrations and in some runs where limited da ta was available. This was generally due to problems with the vacuum system in the MS200.

2-1

## 2-2 To compare the responses of the various inst ruments, we produced scatter plots, Figures 2-18 through 2-21. Figure 2-18 shows the compar ison between the Innova CO and the T15 CO. There is reasonable agreement, but especially at lower concentr ations, we find that the Innova occasionally is much higher than the T15. This may be due to the method the Innova uses, which is to take a grab sample into its internal chamber, measure the components of interest and then evacuate the chamber. If this grab sample is dur ing a particularly high br ief instant, this may result in the higher response seen.

Figure 2-19 compares the two continuous hydrocarbon (HC) measuring devices, the Innova and the TEI. There are two very high values from the Innova, which Figure 2-20 removes. The Innova data are adjusted upward by 10 to account for the expected difference in response from the photoacoustic vs. the FID. Thes e two instruments use fundamentally different methods to measure hydrocarbons and may be hard to compare. In general, the two are tightly correlated, despite the different response factors.

The correlation between the Battelle continuous formaldehyde monitor and the T15 CO is presented in Figure 2-21, without the data from the generator which was significantly higher and dominated the plot. This shows a weak correlation, but includes so me very high values. At more ambient concentrations, they ar e slightly better correlated. We should expect that these two would be correlated as they both are combustion-derived.

2.2 Integrated Samples

Integrated samples consist of canister s, DNPH cartridges (for aldehydes) and Tenax/Carbotrap solid adsorbent traps. Canister data and Tenax/Carbotrap data for ethanol are presented in Table 2-1. In addition to the va lues measured, we show the sum of the BTEX compounds. Of interest was to compare these valu es to the MS200; this comparison is presented in Table 2-2. In this table, the average values (canister) from the variou s exposures are presented along with the corrected MS200 va lues for these same exposures. The corrected data are

calculated as described above (Section 2.1). Generally the av erages agree better at higher concentrations, but lower concentrations are quite reasonable, considering we are working at or

near the detection limit of the MS200. In the case of the resi dential garage e xposures this was further complicated by the 10-minute cycle time between the garage (at high concentrations) and the kitchen (at much lower concentrations). In spite of all this, the correlations between the

canister and the MS200 were on the order of r 2 

## ~ 0.87 and the slopes were ~0.75, with the MS200 reporting less th an the canisters.

The DNPH samples were compared with the av eraged data from the Battelle continuous formaldehyde sampler. This comparison is presented in Table 2- 3 and Figure 2-22. The agreement is excellent for the 10 samples that ar e comparable. The correlation suggests that the Battelle unit is reading about 15% less than the DNPH cartridges are reporting.Table 2-1: Canister and Tenax/Carbotrap Data (concentrations in ppbv)Test IDDateLocation1,3-butadieneEthanol(T/C)MTBEbenzenetolueneethylbenzenem/pxyleneo-xyleneSumBTEXR020226072/26/02Morning FreewayCommute1.020.790.074.3210.770.953.651.2820.98R020226122/26/02Urban canyon,surface0.550.130.041.796.080.632.350.8611.70R020226162/26/02Afternoon FreewayCommute0.68Missing0.042.245.820.531.940.7011.24R020227082/27/02In van, gas station0.16nd0.121.146.720.632.630.9912.11R020227122/27/02Gas station,refueling1.58nd2.0610.3753.382.9312.003.9682.65R020228112/28/02pedestrian walk0.160.470.010.692.290.220.850.314.35R02030109a3/1/02Res. Garage,background0.03Missing0.030.291.670.311.150.503.93R02030109b3/1/02Kitchen, background0.03Missing0.010.311.250.130.490.202.38R02030109c3/1/02Residential garage0.220.980.959.53164.4411.1848.1717.39250.71R02030109d3/1/02Kitchen0.10nd0.363.6655.343.6015.545.6883.82R0203010163/1/02Mobile gasgenerator17.38nd0.5841.03123.239.9534.2112.16220.57



## 2-3Nd = not detectedMissing – missing sampleaa



## 2-4Table 2-DateTable 2-3. Comparison of Formaldehyde DataDate Time Test ID DNPH-HCHO Battelle-HCHO2/26/02 0710R020226076.667.92/26/02 1200R020226129.667.92/26/02 1600R020226166.846.22/27/02 0810R020227084.135.52/27/02 1200R020227124.622/28/02 1100R020228112.301.12/28/02 1503R02028154.963.53/1/02 0935R02030109a3.564.63/1/02 0935R02030109b2.393/1/02 1110R02030109c6.275.43/1/02 1110R02030109d4.155.23/1/02 1600R02030101623.2920.72. Comparison of MS200 with CanistersMS200CanistersSummary Corrected Values, ppbvLocationbenzene toluene ethyl benzem/p-xylene o-xylene Sum Xylenes Benzene Toluene XylenesMorning Freeway Commute 4.32 10.77 0.95 3.65 1.28 4.93 4.38 10.69 5.15Urban canyon, surface 1.79 6.08 0.63 2.35 0.86 3.20 9.20 8.66 4.33 Limite2/26/022/26/02d Dat2/26/022/27/02d DatAfternoon Freeway Commute 2.245.82 0.53 1.94 0.70 2.65 12.53 5.89 4.90In van, gas station1.14 6.72 0.63 2.63 0.99 3.62 9.17 4.71 4.82 Limite2/27/02Data2/28/023/1/023/1/023/1/023/1/023/1/02Gas station, refueling 10.37 53.38 2.93 12.00 3.96 15.96Nopedestrian walk0.69 2.29 0.22 0.85 0.31 1.16 3.11 2.37 2.60Res. Garage, background 0.29 1.67 0.31 1.15 0.50 1.65 2.57 5.21 11.76Kitchen, background0.31 1.25 0.13 0.49 0.20 0.69 8.69 5.84 10.40Residential garage9.53 164.44 11.18 48.17 17.39 65.56 9.30 91.20 46.59Kitchen3.66 55.34 3.60 15.54 5.68 21.22 13.95 66.25 32.15Mobile gas generator 41.03 123.23 9.95 34.21 12.16 46.37 38.33 115.25 51.79

## 2.3 Solid Phase Microextraction (SPME)

We tested the SPME technique during the pilo t study for the collection and analysis of BTEX, MTBE, ethanol, formal dehyde, and acetaldehyde. A 100 μ m (poly)dimethylsiloxane (PDMS) fibers and 75 μ m Carboxen/(poly)dimethylsiloxane (C AR/PDMS) fibers were used for BTEX, MTBE, and ethanol and 65 μ m PDMS/divinylbenzene (DVB) fiber that was impregnated with o-(2,3,4,5,6-pentafluorobenz yl)hydroxylamine hydrochloride (PFBHA) was used for carbonyl compound collection. The fibers were exposed in parallel for 15 min, with exception of the residential garage microenvironment where the fi bers were exposed for 30 min. The fibers were analyzed by inje ction into a GC housed in the m obile laboratory. Some of the fibers were also analyzed by GC/MS. The anal ysis was performed immediately after collection, when possible. However, some of the fibers had to be stored on dry ice in the cooler for a period

of several hours.

The initial SPME results from the pilot study are more qualitative than quantitative. The technique is new method for us and requires additional calibration work in the laboratory. Our major findings from the pilot study include:

• 75 μ m CAR/PDMS fibers are more sensitive than 100 μ m PDMS fibers and are thus more suitable for ambient measurements. We will be using 75 μ m PDMS fibers in the main study for the measurements of MTBE and BTEX.

• Although ethanol peak was observed in all ch romatograms, the etha nol concentrations were clearly too high. This is most probably due to the adso rption of ethanol from breath into the fibers. We measured up to 200 ppbv of ethanol concentr ation in the breath samples collected during this pi lot study. The fibers were situ ated in the br eathing zone during each experiment.

• Formaldehyde and acetaldehyde concentrations are too high as well when compared with continuous formaldehyde analyzer data and integrated DNPH cartridge data. This may also be due to the presence of acetaldehyde in breath (we measured up to 25 ppbv of acetaldehyde in the breath samples). In addition, formaldehyde may be present in the mobile lab where the PFBHA impregnation of the PDMS/DVB fibers took place. We are getting the continuous formalde hyde analyzed from Battelle, thus we do not see any need to monitor formaldehyde with SPME technique and we propose to drop this analysis. Acetaldehyde data are less important for this study and we will obtain this data from integrated DNPH cartridge method.

In summary we are still working on the develo pment of the standard procedures for the SPME technique. The calibration, storage, and op timal sampling time are being addressed. We will be ready for the main study starting in Ju ne and we propose to use the SPME method for

measurements of BTEX and MTBE.

2-5

## 2-6 2.4 Biological Samples

2.4.1 Breath VOC Concentrations

Breath concentrations are portrayed in Tabl e 2-4 and Figures 2-23 through 2-25 for two separate subjects during three separate scripted ex posures. For the pilot pr oject the subjects were two of the technicians collecting samples for micro-environmental concentrations. The objectives of this pilot program for the breath monitoring were to 1) evaluate the ability to analyze breath concentrations of VOC’s accordin g to methods developed by Pleil and Lindstrom (1995), 2) to see differences betw een full and alveolar breath co llections, 3) to assess breath concentrations between two subject s prior to and after scripted e nvironmental exposures, and 4) to develop a recommendation for the final sampling protocol and bi ological monitoring technique of choice. All of the samples shown and discusse d are “alveolar” samples unless designated as “full-breath” samples. Alveolar samples were collected to represent material that has undergone gas exchange in the lung. These sa mples were collected by breathing the end part of a breath directly into an evacu lated cylinder (1 or 3L). The re sults of the breath measurements

are described below.

Refueling

Subject 7: The out of cabin re-fueling experiment showed the highest average exposure concentrations for all of the samples where biolog ical samples were collected, by at least a factor of 5 for most analytes. As expected from results published by Philips and Greenberg (1992), all of the analytes (except MTBE) show a negative al veolar gradient (concen tration in breath lower than ambient air) relative to the average exposure concentrations of 60 minutes. Unfortunately there is no real time data for these compounds, and the elimination rate via breath is rapid enough that real-time levels towards the end of exposure would be most important for these compounds. For subject 7 there is an observed exposure effect, with pos t exposure alveolar concentrations higher than pre-exposure concentr ations by at least a fa ctor of 2. With the exclusion of MTBE and ethyl benzene, this exposure effect was not observed for most compounds in subject 3. Exposure for the outsid e refueling was terminated at 1300 hours. The mobile lab was located approxi mately 1-2 minutes walking di stance away from the exposure area and the exposure subjects were also responsibl e for much of the sampling responsibilities. Expired breath was not collected from subj ect 7 until 1302, and not from subject 3 until 1304. These short differences in times between sample s may explain the lack of an exposure effect observed in subject 3. This can be confirmed by the breath elimin ation half-lives published to be between 1 and 3 minutes for MTBE, benzene, an d toluene (Lindstrom and Pleil, 1996).

In-Cabin Refueling

Subject 7 was the only subject sampled for bo th pre and post samples of the in-cabin refueling exposure. With the exception of MTBE , there is no exposure e ffect. This is most likely due to the fact that the post-exposur e breath sample was no t collected until 0919, 9 minutes after exposure. This may be enough time to eliminate back down to background levels.

## 2-7Table 2-microFuAlvmicroenmicroFuAlv4. Concentrations (ppbv) of volatile organic compounds in breath and micro-environments.Sample Collection Time LocationSubject MTBE benzene toluene ethylbenzene m/p xylene o-xyleneBreath800In Cabin fueling PRE70.32 0.92 2.05 0.330.84 0.23Breath919 In Cabin fueling POST70.79 0.82 1.92 0.330.89 0.23environmentvan, Verdi gas station microenviront conc. 0.12 1.14 6.72 0.632.63 0.99Breath1149Refueling PRE70.35 0.75 1.74 0.330.85 0.27Breath1302Refueling POST73.99 1.83 5.73 1.063.70 1.58Breath1415Midday Background70.08 0.58 1.41 0.001.01 0.32Breath1150Refueling PRE30.22 1.34 2.62 0.001.86 0.41ll Breath1304Refueling POST31.54 1.52 3.16 0.671.76 0.44eolar Breath1305Refueling POST31.84 1.24 2.53 0.481.29 0.31vironmentVerdi gas station, refuel microenviront conc. 2.06 10.37 53.38 2.93 12.00 3.96Breath1415Midday Background30.47 1.10 2.26 0.551.44 0.33Breath1422Midday Background70.80 0.76 1.83 0.000.86 0.25environmentpedestrian walk microenviront conc. 0.01 0.69 2.29 0.220.85 0.31Breath924Morning Background30.28 1.18 2.42 0.631.63 0.00Breath1043Walk PRE30.69 1.56 0.00 0.651.70 0.43Breath1201Walk POST30.31 1.44 3.00 0.731.87 0.45Breath1047Walk PRE70.79 0.99 2.34 0.411.30 0.42Breath1200Walk POST70.32 0.84 2.18 1.165.25 2.18ll Breath1623 Direct Exhaust Exposure30.12 1.36 2.73 0.411.20 0.33eolar Breath1623 Direct Exhaust Exposure30.09 1.38 3.79 0.591.56 0.42

## Pedestrian Walk

Again for the pedestrian walk there is very little exposure effect observed from subject 3 while subject 7 shows at least a factor of 2 increa se in alveolar concentr ations after exposure for ethyl benzene, m/p xylene, and o-xylene. Similar to the refueling samples, subject 3 was did not give their sample at the same time as subjec t 7. There was a one-minute difference between subject 3 (1201) and subject 7 (1200). There wa s a negative exposure effect for MTBE in both subjects, suggesting that pre-exposure background or residual subject concentrations are higher than the exposure. The un-observable exposur e effect for benzene and toluene are not explainable, as the exposure to these compounds was actually higher than the compounds where an exposure effect was observed.

Full versus Alveolar Breath

Figure 2-26 shows the relationship between fu ll and alveolar breath. Full and alveolar breath are defined here by how the sample was collected. Full is th e entire breath blown into the canister sample, while the “alveolar” breath consists of partially reserved tidal volume and some expiratory reserve. The alveolar sample is collected at the end of a regular breath. As observed the agreement between the two br eath collection methods are reas onable, but vary slightly by analyte. Agreement is between 15-25% for MTBE, benzene and toluene; and about 40% for ethyl benzene and the xylenes. In general, th e difference is higher for compounds where the concentrations are less, indicating some contri bution from measurement uncertainty may affect

observed differences. Since the observed concentr ations are higher in the full breath samples (with the exception of MT BE), it is obvious that there are levels of these compounds in the “dead-space” region of the subject that has not undergone any gas exchange. CO 2 

## measurement between the two samples shows a difference of 10%, which is 5% less than the difference observed by Pleil and Lindstrom (1995). 15% is the expected am ount, based on a 15% dilution

of a 1 liter tidal volume. The full and alveolar br eath sample in this pilot study was taken from a 3 liter evacuated canister, which is different than the 1 L canister used by the second subject and in the Pleil and Lindstrom paper. Additiona l experiments should be completed comparing

full/alveolar breath CO2 dilution between the 1 and 3 liter canisters.

2.4.2 Urine VOC Concentrations

Urinary concentrations of MT BE, benzene, toluene, ethylbenzene, and the xylenes were measured for backgrounds and pre/post exposure le vels in two subjects from three scripted exposures. Shown in Table 2-5 are the urinary concentrations of benzene, which was the only urinary constituent consistently above the anal ytical limit of quantitation of 100 ng/L. The objectives of this pilot study was to apply the technique of 1) Fusti noni (1999) to measure urinary volatile organic compoun ds, 2) to measure concentra tions (and variability) in two separate subjects, and 3) to evaluate results in terms of their ability to relate to exposure concentrations. In the original proposal one objective was also to measure urinary creatinine levels. This was not conducted for this report because this is not conduc ted in the contemporary literature to report urinary conc entrations of VOC’s. “Older” literature used to measure

creatinine in order to normalize urinary components for dilution. The current be lief is that this is not necessary. The benzene results are di scussed below for each scripted exposure.

2-8

## In-cabin Refueling

Subject 3 had a high pre-exposure background (208 ng/L) prior to the in-cabin refuel. There was a negative exposure effect after the in-cabin exposure (<100 ng/ L), and a higher concentration one hour after exposure (138 ng/L) th an immediately after exposure. This sample was similar to the next pre-exposure concentration taken one hour later (120 ng/L). Subject 7 had both pre and post exposure levels for the in-cab in re-fuel that were below the detection limit of 100 ng/L (3 x baseline).

Table 2-5. Urinary benzene concen trations in two subjects exposed

to three micro-environents

Benzene Time Date subject activity ng/L 520 227 3 background 118.3 520 227 3 background 141.8 755 227 3 preexpos in cabin refuel 208.1

920 227 3 postexpos in cabin refuel 90.4 a



## 1010 227 3 mid background 139.8 1148 227 3 preexpos refuel 118.6

1308 227 3 post expos refuel 3.1 a



## 1417 227 3 post expos refuel 166.3 1524 227 3 post expos refuel 465.8 1645 227 3 post expos refuel 1100.6

950 228 3 pre walk 276.7 1225 228 3 post walk 335.5

445 227 7 background 163.9

752 227 7 preexposin cabin refuel 26.4 a



## 924 227 7 postexpos in cabin refuel 0.0 a



## 1150 227 7 preexpos refuel 15.4 a



## 1312 227 7 post expos refuel 11.4 a



## 1424 227 7 post expos refuel 18.1 a



## 1620 227 7 post expos refuel 101.8

545 228 7 background 0 a



## 1229 228 7 prewalk 106.5 1415 228 7 post walk 131.0 a: below the limit of quantitation of 100ng/L



## 2-9

## Refueling

Subject 3 showed a negative exposure effect immediately after exposure, but saw a steady increase in urinary be nzene excretion thr oughout the day. Measurements were made approximately every hour until 1645, and the hourly concentrations were 166, 465, and 1100 ng/L at 1417, 1524, and 1645, respectively. This indicates that for these samples the time course for urinary excretion is much slower than it is fo r breath, and there is a lag in the excretion. The exposure concentrations observed for subject 7 were all below 100 ng/L, with the exception of the post exposure sample collected at 1620, where the concentration was about 100 ng/L. These results are comparable to MTBE data repor ted by Lee and Weisel (1998) who showed an increase in urinary MTBE after exposure (1 pp m for 10 min) at about 1 hour, remaining about the same at 3.5 hours and dropping several-fold by 6 hours.

Pedestrian Walk

There was a slight positive e xposure effect for benzene in both subjects from the in-town walk. Subject 3 had a pre-exposure urinary benzene concentrations of 276 ng/L and postexposure concentrations of 335 ng/L, while subj ect 7 had levels of 106 and 135 ng/L. For both subjects the starting background wa s different, and their increase wa s approximately the same for this exposure.

2.5 Results of Additional Refuelin g Experiment (June 4, 2002, Reno)

This experiment was conducted in order to test the respon se of MS200 (since we were not able to operate the instrument during the refueling experiment in February) in this microenvironment and to repeat breath and urine testing to confirm the conclusions drawn from the pilot study. There were important differences between this refueling and the one conducted for the pilot study. Most importantly:

• We only filled the canister during the actual exposure period of 30 min. During the pilot study, we filled the canister over 1 hour, which consisted of 15 min of background plus 45 min of exposure.

• Used one exposure subject rather than two.

• Refueled two vehicles instead of three.

• The MS200 data output was adjusted to sum the xylenes and ethyl benzene using a single library spectra. The reason for this is that there is very little difference between the spectra of these four compounds and we found th at the software did not do well trying to separate them.

In addition to the MS200 and the canister, we also collected 5 breat h samples and 8 urine samples that were analyzed by LRRI. The five breath samples were: Pre test; 15 min into test; approximatelly 2 min post test; 5 min later; a nd 10 min later. The urin e samples included: pretest; approximately15 min post exposure (no urin ary output between these two); approximately

2-10

## every hour thereafter for 6 more hours. All the vo ids from the test subj ect between the hours of

0730 and 1800 were collected.

2.5.1 MS200 and Canister Results

Figure 2-27 shows the time series of the concen trations of benzene, toluene and the sum of xylenes and ethylbenzene in parts per million by volume, ppmv. The data are one-minute averages recorded by the MS200. To convert this unit to canister data units (which are parts per billion of carbon or ppbC), multiply by the number of carbons and by 1000 to adjust ppm to ppb. For example, the highest spike seen (at a ppx 21 min) is 0.173 ppmv for toluene, which is equivalent to 1211 ppbC. Benzene in the same sp ike is 0.104 ppmv or 624 ppbC. Sum of xylenes highest reading at about 22 min is 0.135 ppmv or1080 ppbC.

The averages of the MS200 data are in good agreement with the can ister measurements. The data are as follows (units are ppbC):

Compound MS200 (ppbC) Canister (ppbC) % error

(difference/can value)



## Benzene 128.2 142.1 9.7

Toluene 413.8 438.4 5.6 Sum Xyl+EBz 336.6 368.2 8.6

2.5.2 Breath Sample Results

As explained above, the breath samples were co llected in 1-liter stai nless steel canisters from one subject. Table 2-6 below lists the resu lts obtained from these samples (the units are ppbC):

Table 2-6 Breath Data in ppbC

Site/Compound Pre refueling

breath Middle of run

breath Post exposure breath #1 (2 min) Post exposure breath #2 (5 min) Post exposure breath #3 (10 min)

sample_time (hr) 0945 1046 1103 1107 1111

sample_date 6/4/02 6/4/ 02 6/4/02 6/4/02 6/4/02

1,3-butadiene 0.21 0.83 7.46 0.44 0.41

MTBE 0.00 3.03 1.34 1.91 1.14

benzene 2.65 14.76 7.82 10.76 9.78

toluene 5.98 47.32 123.54 27.59 25.17
ethyl benzene 0.83 1.01 2.77 8.46 7.75 m/p-xylene 2.61 14.12 18.77 28.75 46.36
o-xylene 1.66 5.59 3.82 7.03 16.88



## 2-11

## These data are consistent with the data obtained during the pilot study, confirming very

short breath elimination half-liv es of the compounds measured. In addition, this elimination time is different for every compound. Whereas benzene concentration is the highest in the middle point of the exposure, and declines signif icantly two minutes after exposure, toluene concentrations are the highest 2 min after expo sure, declining sharply five minutes after the exposure. Thus, breath data obtained after an in tegrated exposure period of an hour will not accurately measure the biological uptake that occurs under variable condition during the exposure period.

2.5.3 Analysis of Urinary VOC Concentrations

Urinary concentrations of MTBE , benzene, toluene, ethyl Be nzene, and the xylenes were analyzed utilizing the same methods described fo r the Reno pilot study protocol. In addition, for these data we analyzed urinary creatinine values and urinary ethanol. Creatinine values were obtained using a standard creatinine analysis kit on a Monarch 2000 clinical chemistry

instrument. Ethanol data were obt ained utilizing the same solid pha se extraction fibers that were used for the other chemical species.

Table 2-7 lists the concentrations of measur ed species, including creatinine, and Figure 2- 28 shows the data for BTEX and MTBE. Urinary concentrations of all of the measured VOC’s except ethanol were present in detectable limits in most of the samples. The absence of ethanol may be due to the high detection limits of (0.5 ng/L) relative to the other analytes, which are

detectable in much lower concentrations. If urinary ethanol is to be monitored in follow on studies additional method development will be c onducted to decrease the limits of detection on this assay.

Concentrations of the other volatile organi cs reported here are complicated by the relatively high concentration observed in the pre-exposure samples. Concentrations postexposure increased throughout the day for benzene and toluene, which is similar to what was observed in the pilot study. Howe ver, at their peak, the concentr ations of these compounds were only slightly larger than the pr e-exposure backgrounds. The concen trations observed in the urine for benzene were consistent with what was observed during the pilot study and in the literature, with values in the range of 100-200 ng/L. Th e concentrations post-ex posure did not increase much beyond 200 ng/L for benzene. These low post- exposure concentrations are consistent with the results from subject 7. While the highest urinary concentrations for subject 7 in this study do not reach levels reported for subject 3 in the p ilot study, subject 7 does show an increase in urinary benzene and toluene through out the day, which is consistent with subject 3 in the pilot study. The currently reported results do show concentr ations of toluene that are increased relative to benzene, which is consistent with the higher concentrations of toluene that the subject was exposed to. The toluene concentrations do not , however, increase well above the pre-exposure background concentrations.

Creatinine was measured during this follow-on study in response to some criticism from

an external reviewer that crea tinine values would help determine concentration effects resulting from dilution. As reported in th e pilot study report, th e concentrations of urinary VOC’s in the contemporary literature are typica lly not normalized to creatinine concentrati on. One example of the rationale for not using creatinine correction is given in Albertin e et al. (2001), where

2-12

## 2-13 statistical relationships between exposure and urinary concentra tions of butadiene biomarkers were more significant when not normalized.Table 2-7Concentrations of Ethanol, MTBE and BTEX in urine samples (ng/L)



## 2-14Re-do of Refueling ExperimentConcentrations in ng/LSample#SubjectTimeDateDescriptionEthanolMTBEBenzeneTolueneEthBenzenep/mxyleneo-xyleneCreatininegm/dL178206/4/02pre exposure-morningnd0.0240.1650.2650.0620.0570.08072711156/4/02post exposurend0.0520.1030.1120.0390.0390.066333712156/4/02post exposurend0.0300.1350.1490.0570.0570.098564713276/4/02post exposurend0.0330.0890.1350.0470.0460.066235714306/4/02post exposurend0.0210.1430.2020.0510.0350.066266715226/4/02post exposurend0.0170.2030.2830.0420.0420.066137716246/4/02post exposurend0.0090.2380.2790.0510.0440.071138717186/4/02post exposurend0.0130.1060.1140.0460.0400.07022

## 3. RECOMMENDATIONS

This section describes the equipment and protocols we recommend for this program. We first summarize the equipment in Table 3- 1 and then discuss each individually.

Table 3-1 Recommendation Summary

Instrument Recommendation Notes

Battelle HCHO Yes We have requested Battelle build one for DRI.

Kore MS-200 Yes Needs protocol development and possibly

preconcentrator.

TEI TVA1000 No Not sensitive enough.

Innova

Photoacoustic No Grab sampling method; overlap with other

instruments. Langan T15 CO Yes Need to develop temperature dependence. Integrated Samples Yes

SPME Yes Would be used only for MTBE and BTEX

3.1 Exposure Measurements

Formaldehyde Monitor . The Battelle instrument appears to have performed quite well. We

evaluated a similar commercial instrument made by Alpha Omega during a three-day evaluation period at the end of May 2002. The evaluation consisted of collocated measurements with our CO analyzer, Kore MS200 analyzer and integrated DNPH measurements using microenvironmental exposures similar to those used during the pilot study. Base upon the results of this evaluation, we conclude d that the Alpha Omega HCHO monitor would be suitable for the main study.

Kore MS200 . The MS200 appears to have performed rather well in the pilot study. We are currently refining the protocol fo r using this instrume nt, based on the results from the field study as well as the results of many e xperiments we have conducted since that time. We hope to install an automated system for zeroing the instrument dur ing the run times to confirm the zero point of the instrument as it changes during the day. In addition, we will be standardizing the zeroing procedure and are working on methods to auto mate the background subtraction process. We recommend the use of the instrument in the main study.

TEI TVA1000 . The TVA1000 is a FID based detector for total hydrocarbons. As such it responds approximately equally to the concentra tion of oxidizable carbon in the air. In the present experiment that means it has the ch allenge of measuring small amounts of the hydrocarbons of interest in the presence of a relatively high concentration of methane. In

3-1

## addition since there is no specia tion, we are not obtaining any information about the relative contribution of any of the components. Also, the ba seline is not very stab le and we do not think it

adds a lot of useful information. Our recomm endation is to not use this instrument.

Innova Photoacoustic . This instrument can measure CO, CO 2 

## , total hydrocarbons and water vapor (dew point). However, the instrument is no t a true “continuous” monito r, but rather it takes grab samples, measures that sample and then takes another grab sample. This means that the value determined may not accurately represent the average over the time period it is applied to. We feel that a better way to obtain total hydrocarbons is to compar e CO and BTEX from continuous instruments to the same compounds in the canisters. Our reco mmendation is to not

use this instrument.

Langan T15 CO monitor. This instrument appear s accurate and easy to use in addition to being portable with very low power consumption. It is , however, temperature dependant and we will need to develop a temperature based calibration to maintain accuracy. In addition, it appears to have a slower response time, es pecially post-exposure to a high concentrati on, but this was only noticeable in the extreme case of the generator at DRI where concentration changes were over 100 ppm in less than 1 minute. We do recommend using this instrument.

Integrated Samples . We recommend collecting integrated samples as a check on the continuous samples and to get more detailed speciation of VOCs. The association between the continuous

CO and BTEX data with the data from time-inte grated measurements can provide estimates of the time series for species wi thout feasible methods for con tinuous measurement such as 1,3 butadiene, acetaldehyde, et hanol, MTBE, and total nonmethane hydrocarbons..

SPME . Based on our pilot study, we consider this technique as very promising. We propose to use SPME for MTBE and BTEX, but not for etha nol, formaldehyde and acetaldehyde. We are currently working on perfecting ou r calibration procedure. We ar e also performing the series of experiments to determine th e optimal exposure time and the dependence of measured concentrations on storage conditions.

3.2 Recommendations for Measurements of VOC in Breath

During the pilot study breath concentrations of MT BE, benzene, toluene, ethylbenzene, and the xylenes was successfully conducted. Analysis of alveolar and full breath showed that the sampling technique to target alveolar breath excluded contributions of VOC’s present in the “dead-space” air present in a full breath becaus e their concentrations were lower. Breath concentrations between the two separate subjects differed in many cases most likely because of slight differences in the time of sample collecti on. This is because the breath elimination halflives of the compounds measured are between 1 and 3 minutes (Lindstrom and Pleil, 1996), so slight differences in the time of collection can make large differences in observed breath concentrations. This can also explain why for many of the samples there was little or no exposure effect observed. These samples were generally collected minutes af ter the end of the exposures, after which much of the target compounds would have been eliminated. This effect was observed by Lioy et al. (1991), who saw little co rrelation with breath benzene concentrations and microenvironmental exposure concentrations, a nd attributed their lack of agreement to the

short time course of benzene elimination via breath.

3-2

## When collected in exposure environmen ts where the concentrations are above background (e.g. refueling) there is an observable exposure effect when the sample is collected very close to the end of exposure. However, these breath concentrations will only reflect what the subject is exposed to in the last portion of the exposure, as the ma jority of the one-hour exposure will have been eliminated by the time the samples are collect ed. Therefore single

breath measurements at the termination of e xposures are not a good in dex of cumulative onehour exposures. Therefore, we do not recomm end breath measurements for urban exposure experiments during the main study.

3.3 Recommendations for Measurement of VOC in Urine

The method of Fustinoni (1999) based on a se nsitive SPME technique was developed for application to this study. Work at LRRI was conducted with the same instrument as used in that study, but the published quantitation limits of 12-34 ng/L were not attainable. We were able to observe good signal/noise for all of the analytes in what would likely be the sensitivity range published by Fustinoni (1999). However, the de uterated internal st andards utilized for quantitation had small amounts of the parent (u n-deuterated) compound pr esent that limited the limit of detection. The area counts of the parent compound in blanks showed integrated area counts from the mass spectrometer of approximately 600 for benzene, when the 100 ng/L

standard had area counts of about 2500. The use of the internal standards is necessary to reduce sample to sample variability in the uptake of the VOC’s by the SPME fiber.

Because of the low exposure concentrations observed in this study, the amount of urinary benzene and other VOC’s were extremely low. Although published excretion rates vary, a typical amount of un-metabolized benzene rela tive to exposure is on the order of 0.1% (Waidyanatha et al. (2001)). Fu stinoni (1999) showed urinary concentrations of benzene to be around 114 ng/L after an approximate 3.5 ppb exposur e, and Waidyanatha et al. (2001) have shown 145 ng/L concentrations in “non-exposed” subjects from an occupational exposure study. Similarly, Ghittori et al (1995) showed back ground levels of benzene in non-smokers of approximately 131 ng/L (geometric mean). Most of the urinary benzene concentrations observed in the currently reported pilot st udy are in the range of the low level exposures from previous

studies described above. Since the scripted exposures were low there was no strong correlation between exposure and urinary benzene in the pilot study. This is slightly in contrast to published results of Waidyanatha et al. ( 2001), who saw an exposure effect with benzene, but the exposure concentrations were in the ppm range.

After the highest exposure ther e was a relatively strong exposure effect observed in one subject and a lesser exposure effect observed in a second subject. There was a time course in the elimination of benzene that showed urinary benz ene concentrations increasing with time. These results are comparable to MTBE data repor ted by Lee and Weisel (1998) who showed an increase in urinary MTBE after exposure (1 pp m for 10 min) at about 1 hour, remaining about the same at 3.5 hours and dropping several-fold by 6 hours. Here urinary concentrations were only measured 3 hours post exposure, so we were not able to observe the start of elimination from the body. Because of an inab ility to see the decay of urinar y benzene after exposures, and the slight inconsistency in the two subjects ( one showed much higher urinary benzene), we repeated this highest end exposur e on June 4, 2002, to see if the urinary VOC concentration data

3-3

## can be linked strongly to an expos ure effect at these levels and to see the full time course of

elimination.

Because the additional measurements of ur inary MTBE/BTEX from the second refueling experiment were promising, we recommend this measurement as the biomonitoring technique of choice. We will pay special attention to the pre-exposure background urine sample collection, making sure that the subject is not exposed to gasoline exhaust at least 10 hours pr ior to sample

collection. Since we were not able to discrimina te urinary benzene concen trations in low-level exposures (e.g. walking down street), we pr opose to only conduct biomonitoring experiments from projected “high-end” exposures such as re fueling. Monitoring will be conducted similar to the pilot study, with pre and post exposure collections of the s ubject’s urine.

3-4

## 4. REFERENCES

Albertini et al. (2001). Chem. Boil ineract. Vol 135-137, pg 429-453

Fustinoni, S., R. Giampiccolo, S. Pulvirenti, M. Buratti, and A. Colombi (1999). Headspace solid-phase microextraction for the determina tion of benzene, toluene, ethylbenzene and xylenes in urine. J. Chromatogr. B 723 : 105-115.

Ghittori, S., Maestri, L., Fiorentino, M.L. and Imbriani, M. (1995). Evaluation of occupational exposure to benzene by urin alysis. Int. Arch. Occup. Environ. Health, 67, 195-200

Lee, C.W. and C.P. Weisel (2001). Toxic okinetics of Human Exposure to Methyl tertiary-butyl ether (MTBE) Following S hort-Term Controlled Exposures. J. Exposure Anal. And Environ. Epi., 11, 67-78

Lindstrom, A.B., and J.D. Pleil (1996). Alveol ar Breath Sampling and Analysis to Assess Exposures to Methyl Tertiary Butyl Ether (MTBE) During Motor Vehicle Refueling., J. Air and Waste Management, V. 46, p. 676-682

Lioy, P.J., Wallace, L., and E. Pelizzari ( 1991). Indoor/Outdoor, and Personal Monitor and Breath Analysis Relationships for Se lected Volatile Organic Compounds Measured at Three Homes During New Jersey Team, J. Exposure Anal. And Envir. Epi., Vol. 1, No. 1, pp 45-61

Philips, M. and J. Greenberg (1992). Ion-Trap Detection of Volatile Organic Compounds in Alveolar Breath, Clin. Chem. 38/1, 60-65

Pleil, J.D., and A.B. Lindstrom (1995). Collec tion of a Single Alveolar Exhaled Breath for Volatile Organic Compound Analysis., Amer ican J. Industrial Medicine, 28; 109-121

Waidyanatha, S., N. Rothman, S. Fustinoni, M. T. Smith, R. B. Hayes, W. Bechtold, M. Dosemeci, L. Guilan, S. Yin, and S. M. Rappaport (2001). Urinary benzene as a biomarker of exposure among occupationally exposed and unexposed subjects. Carcinogenesis 22 : 279-286.

4-1

## FIGURE FOR SECTION 2Figure 2-1 ConcentrationTime Series, Freeway AMFreeway AM (R02022607)0.05.010.015.020.025.0 7:10 7:15 7:20 7:25 7:30 7:35 7:40 7:45 7:50 7:55 8:00 8:05CO0.02.04.06.08.010.012.0HC & HCHObkgdCO(ppm)T15 CO(ppm)THC byFID(ppm)HCHO(ppb)F-1Figure 2-2 Concentration Time Series, Surface StreetsSurface Streets (R02022607)0.02.04.06.08.010.012.014.016.018.020.0 12:00 12:05 12:10 12:15 12:20 12:25 12:30 12:35 12:40 12:45 12:50 12:55CO0.02.04.06.08.010.012.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-2Figure 2-3 Concentration Time Series, Freeway PMFreeway PM (R02022616)0.05.010.015.020.025.0 16:00 16:05 16:10 16:15 16:20 16:25 16:30 16:35 16:40 16:45 16:50 16:55CO0.02.04.06.08.010.012.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-3Figure 2-4 Concentration Time Series, Refueling In-CabinRefueling In-Cabin (R02022708)0.01.02.03.04.05.06.07.08.09.010.0 8:10 8:15 8:20 8:25 8:30 8:35 8:40 8:45 8:50 8:55 9:00 9:05CO0.01.02.03.04.05.06.07.0HC & HCHObkgdCO(ppm)T15 CO(ppm)THC byFID(ppm)HCHO(ppb)F-4Figure 2-5 Concentration TimeSeries, Refueling out of cabinRefueling Out of Cabin (R02022712)0.01.02.03.04.05.06.07.0 12:00 12:05 12:10 12:15 12:20 12:25 12:30 12:35 12:40 12:45 12:50 12:55CO0.05.010.015.020.025.030.035.040.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)F-5Figure 2-6 Concentration TimeSeries, Walking DowntownWalking Downtown (R02022811)0.01.02.03.04.05.06.07.0 11:00 11:05 11:10 11:15 11:20 11:25 11:30 11:35 11:40 11:45 11:50 11:55CO0.01.02.03.04.05.06.07.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC asPropane(ppm*10)HCHO(ppb)F-6Figure 2-7 Concentration TimeSeries, Underground GarageUnderground Garage (R02022815)0.02.04.06.08.010.012.0 15:00 15:05 15:10 15:15 15:20 15:25 15:30 15:35 15:40 15:45 15:50 15:55CO0.01.02.03.04.05.06.07.08.09.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-7Figure 2-8 Concentration Time Series, Residential Garage Background AResidential Garage Background A (R02030109a)0.00.10.20.30.40.50.6 9:35 9:40 9:45 9:50 9:55 10:00 10:05CO0.01.02.03.04.05.06.07.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-8Figure 2-9Concentration Time Series, Residential Garage Background BResidential Garage Background B (R02030109b)0.00.10.10.20.20.30.30.40.40.50.5 10:05 10:10 10:15 10:20 10:25 10:30 10:35CO0.01.02.03.04.05.06.07.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-9Figure 2-10 Concentration Time Series, Residential Garage Sample CResidential Garage Sample (R02030109c)0.00.10.20.30.40.50.60.70.8 11:10 11:15 11:20 11:25 11:30 11:35 11:40CO0.02.04.06.08.010.012.014.016.018.0HC &HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-10Figure 2-11 Concentration Time Series, Residential Garage Sample DResidential Garage Sample (R02030109d)0.00.10.20.30.40.50.60.70.80.91.0 11:40 11:45 11:50 11:55 12:00 12:05 12:10CO0.02.04.06.08.010.012.014.016.018.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-11Figure 2-12 Concentration Time Series, Residential Garage Sample EResidential Garage Sample (R02030109e)0.00.10.20.30.40.50.6 12:10 12:15 12:20 12:25 12:30 12:35 12:40CO0.02.04.06.08.010.012.014.016.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-12Figure 2-13 Concentration Time Series, Residential Garage Sample FResidential Garage Sample (R02030109f)0.00.20.40.60.81.01.21.41.61.82.0 12:40 12:45 12:50 12:55 13:00 13:05 13:10CO0.02.04.06.08.010.012.014.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-13Figure 2-14 Concentration Time Series, Residential Garage SampleGResidential Garage Sample (R02030109g)0.00.10.20.30.40.50.60.70.80.9 13:10 13:15 13:20 13:25 13:30 13:35 13:40CO0.01.02.03.04.05.06.07.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)F-14Figure 2-15 Concentration Time Series, GeneratorResidential Garage Sample (R02030116)0.0100.0200.0300.0400.0500.0600.0700.0800.0900.0 16:00 16:05 16:10 16:15 16:20 16:25 16:30CO0.020.040.060.080.0100.0120.0HC & HCHObkgdCO(ppm)T15 CO(ppm)InnovaCO(ppm)THC byFID(ppm)THC asPropane(ppm*10)HCHO(ppb)Generator Sample(R02030116)F-15Figure 2-16 MS200 Raw and Corrected DataFreeway AMMS200 Raw Benzene, Zero, and Corrected-0.0100.010.020.030.040.050.060.070.080.090.10.11

ppmv0:00:00 0:07:12 0:14:24 0:21:36 0:28:48 0:36:00 0:43:12 0:50:24 0:57:36 1:04:48Elapsed timebenzenebz zerobz corrF-16Figure 2-17 MS200 Corrected Data OnlyFreeway AMMS200 Corrected Data Only-0.0100.010.020.03

ppmv0:00:00 0:07:12 0:14:24 0:21:36 0:28:48 0:36:00 0:43:12 0:50:24 0:57:36 1:04:48Elapsed timebz corrtol corrxyl corrF-17Figure 2-18. Correlation between CO by T15 and by Innova.y = 0.8754x + 0.4195R2= 0.7709024681012141618

Innova CO (ppm)024681012141618T15 CO (ppm)F-18Figure 2-19 Correlation between Innovaand TEI for total hydrocarbons.Chart Titley = 0.0703x + 3.0835R2= 0.287802468101214020406080100120140Innova HC as propane (ppm*10)

TEI HC as methane (ppm)F-19Figure 2-20 Innova vs.TEI for total hydrocarbons with three outliers removed.Chart Titley = 0.209x + 2.4854R2= 0.68190.002.004.006.008.0010.0012.0014.0016.0018.00

TEI HC as methane (ppm)0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00Innova HC as propane (ppm*10)F-20F-21Figure 2-21 Correlation betweenCO and formaldehyde.y = 0.5062x + 4.5338R2= 0.262102468101214160510152025T15 CO (ppm)

Battelle HCHO (ppb)

## Figure 2-22 Correlation between DNPH and continuous formaldehyde.

F-22 

## HCHO

y = 0.8543x + 0.6638

R 2



### = 0.9532

15 20 25

25le-HCHO



### 0

5 10

0 5 10 15 20

DNPH-HCHOBattelFigure 2-23. Pre and post exposure breath samples during refueling.Refueling01234567mtbebenzetolueetbzmp_xylo_xyl

ppbv7 Refueling PRE7 Refueling POST3 Refueling PRE3f Refueling POSTF-23Figure 2-24 Pre and post exposure breathsamples during in-cabin fueling.In-cabin Fueling00.511.522.533.544.55mtbebenzetolueetbzmp_xylo_xyl

ppbvIn Cabin fueling PREIn Cabin fueling POSTF-24Figure 2-25 Pre and post exposure breath samples during walk.Walk012345678910

ppbvmtbebenzetolueetbzmp_xylo_xylWalk PREWalk POSTWalk PREWalk POSTF-25Figure 2-26 Relationship betweenfull and alveolar breath.Realationship Between Full and Alveolar Breath0.000.501.001.502.002.503.003.50MTBEbenzenetoluene ethylbenzene m/p xylene o-xylene

ppbvFull BreathAlveolar BreathF-26Figure 2-27The three traces; benzene, toluene and sun of xylenes andethylbenzeneRefuel00.020.040.060.080.10.120.140.160.180.20:00:000:07:120:14:240:21:360:28:480:36:00Elapsed time

ppmvBenzeneTolueneSum xylenes+ethylbenzeneF-27Figure 2-28 Data for BTEX and MTBE0.0000.0500.1000.1500.2000.2500.3000 2 4 6 810Sample Number

ng/LMTBEBenzeneTolueneEth Benzenep/m xyleneo-xylenePre-exposure Post exposureF-28