TRANSPORTATIONRELATED AIR POLLUTANT EXPOSURE Implications for Regional Policies

TRANSPORTATION-RELATED AIR POLLUTANT EXPOSURE: Implications for Regional Policies and Public Health Arthur M. Winer, Ph. D. Professor of Environmental Health Sciences School of Public Health University of California, Los Angeles Transportation/Land-Use/Environment Symposium October 16 -18, 2005 Lake Arrowhead

INTRODUCTION • The contribution of transportation-related pollutant emissions to regional photochemical smog has been recognized for many decades • In contrast, only more recently have the exposures and health impacts due to localized transportationrelated emissions been characterized • This new characterization resulted from – A paradigm shift in air pollutant exposure assessment – New physical measurements and health studies in close proximity to roadways and other transportation facilities 2

PARADIGM SHIFT IN EXPOSURE ASSESSMENT “The Place Makes The Poison” Kirk Smith UC Berkeley School of Public Health 3

EXPOSURE ASSESSMENT PRINCIPLE Measure air pollutants in the “microenvironments” where people spend their time (rather than where air monitoring stations long distances away are measuring outdoor air). 4

EXAMPLES OF TRANSPORTATIONRELATED MICROENVIRONMENTS • Near-roadway environments • Passenger vehicle compartments • School buses • Near-roadway structures (schools pre-schools, homes) • Proximity to ports, airports, rail, etc. 5

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HEALTH IMPACTS OF VEHICLE EXHAUST • Over the past decade, dozens of studies from all over the world have shown that spending time in close proximity to heavy traffic, especially diesel truck traffic, is associated with a wide range of morbidity effects, as well as increased mortality • Diesel exhaust particulate (DEP) declared a toxic air contaminant by ARB in 1998 8

RELATIVE POLLUTANT CONCENTRATIONS vs DISTANCE FROM I-405 FREEWAY (Zhu et al. , 2002 a) 9

710 Freeway 10

Relative Particle Number, Particle Mass, Black Carbon, and CO Concentrations vs. Downwind Distance from I-710 (Zhu et al. , 2002 b) 11

ULTRA-FINE PARTICLES (UFP) • Because of dilution (and coagulation) UFPs behave like a “local” source • Central station monitoring is not useful for estimating UFP exposure and dose • A 1 -hr exposure on a freeway exceeds 23 hrs of exposure away from freeways 12

Influence of Vehicle Type and Exhaust Location on Exposure in Following Vehicle (Sources: Rodes et al. , 1997; Fruin et al. , 2004) 13

IN-VEHICLE EXPOSURE • Highly elevated roadway pollutant concentrations have profound implications for in -vehicle exposures: – In-vehicle concentrations of black carbon can be many times those in “background” ambient air – Ultra-fine particles are up to ten times higher on roadways compared to “background” air – The 6% of the day spent in a vehicle can account for ~1/3 to >half of daily exposure to DEP and 14 greater than 90% of daily exposure to UFP

Children’s Pollutant Exposure During School Bus Commutes UCLA: Eduardo Behrentz, Lisa Sabin, Seong Lee, Kathleen Kozawa, Steve Colome and Arthur Winer UC Riverside: Dennis Fitz and David Pankratz 15

BACKGROUND • Children are a vulnerable population • 70% of school buses in California are powered by diesel engines and DEP is a TAC • Children may be exposed to high concentrations of diesel particles and gases during bus commutes, at school bus stops, or at loading/unloading zones • Some children in southern California spend up to three hours a day on school buses 16

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Mean Pollutant Concentrations in Bus Commute Related Microenvironments & Background Air (Sabin et al. 2005) Mean Concentrations Backgrounda Loading/ Unloading Bus Stops Zone Bus Commutesb, c BC (mg m-3) 2 ± 0. 1 2 ± 0. 3 4 ± 0. 4 3 - 19 (8) PB-PAH (ng m-3) 27 ± 1. 5 15 ± 0. 3 44 ± 4. 5 64 - 400 (134) NO 2 (ppb) 49 ± 1. 0 35 ± 0. 2 54 ± 1. 9 34 - 110 (73) PC count cm-3)d 83 ± 3. 1 N/C 62 ± 1. 8 77 - 236 (130) PM 2. 5 (mg m-3) 20 ± 2. 4 e N/C 25 f 21 - 62 (43) N/C = Concentration data were not collected; a. These values were measured around Los Angeles with the bus parked, engine off, and with the windows fully open and represent urban ambient air background concentrations during the study; b. The ranges are associated with the different bus types and window position (open and closed); c. The values within parentheses are the means for all runs; d. In 0. 3– 0. 5 um 21 size e f range; From published data for Los Angeles basin. Not enough data to establish a confidence interval.

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KEY FINDINGS • In terms of exposure, bus commutes are much more important than bus stops or loadingunloading zones. • Peak pollutant concentrations occurred for close proximity to other diesel vehicles and when idling (due to bus’s own exhaust). • Impact of a bus’s own exhaust is most important when windows are closed due to self-pollution. • Cleaner fuels (e. g. CNG) and particle traps reduce pollutant concentrations inside bus. 24

Recommendations for Reducing Children’s Exposure During School Bus Commutes • Minimize time spent on sidewalks in front of schools when diesel school buses are arriving or departing. • Assign the cleanest buses to the longest routes. • Instruct school bus drivers to avoid other diesel school buses. • Develop strategies to shorten commute times. • Instruct school bus drivers to turn off engines immediately on arrival at a school; do not turn engines on until ready to depart. • Properly maintain in-use diesel school bus engines to eliminate visible exhaust. • Phase out conventional diesel school buses and replace 25 with cleaner buses, such as CNG or trap-outfitted diesel.

GOODS MOVEMENT FROM THE PORTS Exposure Impacts Along Transportation Corridors

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Where is this cargo going and how will it get there? 28

HOW CARGO CONTAINERS LEAVE THE PORTS According to Alameda Corridor Transportation Authority (ACTA): – 50% by big-rig diesel trucks directly to businesses or to distribution warehouses • Warehouses in Riverside & San Bernardino Counties where cargo is sorted and sent to other cities/states – 25% by truck on I-710 to intermodal facilities where containers transfer to trains • Downtown L. A. , East L. A. , Commerce – 25% onto Alameda Corridor, a 20 -mile express railroad to downtown Los Angeles 29

Trucks on the Terminal Island Freeway 30

Terminal Island Fwy Hudson School Community Park 31

“Protecting” residents and students: a chain link fence! 32

POLICY IMPLICATIONS • . 33

REDUCING VEHICLE EMISSIONS: A TRIPLE WIN • Phase out dirtiest school buses • Maintain buses to eliminate visible exhaust • Encourage more rapid turn-over or retrofit the dirtiest diesel trucks • Eliminate “super emitter” passenger cars • Adopt remote sensing and buy/crush plans • Electrify diesel transfer stations and cargo ship docks (ie. reduce diesel idling) • Adopt more stringent fuel economy 34 standards

LIMITS OF TECHNICAL FIXES • > 50% of reductions in 2003 AQMP are in a “black box” of undefined measures • SCAQMD says they are out of viable options for cleaning up stationary sources • ARB’s ZEV program failed • Hybrids do not provide dramatic benefits • The “Hydrogen Highway” is pure hype • Major regulatory barriers exist to reducing marine and air traffic emissions • CONCLUSION: We must reduce VMT as well as emissions! 35

SMART GROWTH IMPLICATIONS • Reduce VMT and “cold starts” through “Smart Growth” strategies: – Create housing next to jobs and services – Use mass transit hubs as foci for housing – Promote mixed use and infill • But must avoid: – High density housing in close proximity to major roadways – Impacting residents with toxic air emissions from close-by industrial or retail sources 36

ENVIRONMENTAL JUSTICE • New EJ issues raised by our understanding of localized impacts of vehicle emissions: – Health disparity concerns may be overlooked by typical regional AQ “conformity” process – Non-white children 3 -4 times more likely to live in areas with high traffic densities – UCLA research shows minority and high-poverty neighborhoods in LA bear over two times the traffic density of rest of So. Cal. – These findings add to traditional concerns about disproportionate impacts of toxic release facilities and other stationary air pollutant sources in minority communities 37

CONCLUSIONS • AQ problems occur at two distinct scales: – Regional smog vs localized vehicle/facility impacts • Addressing both poses new challenges for government, the private sector and the public: – Growth in region may prevent us from reaching AQ goals absent new approaches – We need a new paradigm: • • • Reduce diesel emissions from all sources Develop effective strategies to reduce VMT Eliminate gasoline “super emitters” Create real and/or virtual “Buffers” along major roadways Pay attention to EJ issues posed by direct vehicle emissions – Will require greater cooperation and integrated policy approaches across “disciplinary” agencies 38