Personal exposure assessment to air toxics in BRTs: Metrobus Insurgentes, Mexico City

Seventh Annual Transforming Transportation

Washington, D.C. January 13 th, 2010

Beatriz Cárdenas González

Instituto Nacional de Ecología

Outline

• INE: air pollution, transportation, GHG

• The impact of a Bus Rapit Transit System on Commuter‘s exposure to air pollutants in Mexico City: Metrobus Insurgentes 2004-2005

• Current projects:– Zero Emisions Corridor, Mexico City 2008 – Ruiz Cortines Corridor, Monterrey 2009

• Lessons learned and Next steps

4

Credits Credits

-• INE

– Adrian Fernández, President – Leonora Rojas and Victor Gutiérrez Avedoy– Project participants

• Henry Wöhrnschimmel, Beatriz Cárdenas, Miriam Zuk *

• Gerardo Martínez**, Julia Cerón• Salvador Blanco, Arturo Campos, Jepthé Cruz, Teresa Ortuño

• CTS– Adriana Lobo, Hilda Martínez

• Nuevo León State Goverment • Idolina de la Cerda, Juan Marin, Jaime Garza

• Hewlett Fundation • Embarq

INE

Climate Change ProgramEcosystems conservation  Chemicals, Urban and Regional pollution    National Center for Environmental Research and Training Environmental Policy and Economy   

Ministry of Natural Resources and Environment

National Institute of Ecology (technical and scientific branch)

Trends of Air quality in Mexico City Metropolitan Area: Ozone and CO

Source: http://www.sma.df.gob.mx/simat2/

Ozone

Carbon monoxide (CO)

Trends of PM in Mexico City Metropolitan Area

Source: Retama, 2009. http://www.sma.df.gob.mx/simat2/

Trends of the different PM fractions in MCMA

0

50

100

150

200

2501

99

0

19

91

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

20

06

20

07

20

08

Ind

ice

de

la m

ed

ia a

nu

al r

ela

tiva

(%

)

Año

PM10 PST PM2.5 Pb

Source: Retama, 2009. http://www.sma.df.gob.mx/simat2/

Trends of PM2.5 in Mexico City Metropolitan Area

Source: Retama, 2009. http://www.sma.df.gob.mx/simat2/

Carbon monoxide trends in Mexico city: in public transportation (personal exposure) and ambient air

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

010

2030

4050

60

año

CO

, exp

osic

ión

pers

onal

(pp

m)

01

23

45

6C

O a

mbi

enta

l (pp

m)

Introducción del convertidor catalítico para vehículos a gasolina modelo 1991

MicrobúsAutobúsAmbiental

Personal exposure

concentration

Ambient concentration

Introduction of Catalytic converter

Mexico City air monitoring

network

Impact of interventions: effect on communter´s personal exposure to air toxics and air pollutants

.

©©

Personal exposure to air toxics

Inventario Nacional de Emisiones de Gases de Efecto Invernadero 2006 . Contribución por sector (INE, 2009)

Procesos Industriales

7%

Agricultura6%

Cambio de uso de suelo y silvicultura

13%

Desechos14%

Funtes fijas y de área33%

Transporte20%

Emisiones fugitivas7%

Energía60%

711 million of tons CO2 eq./year

Power plants 20.7%Construction and manufacturing 7.9%Other sectors (residential included) 4.4%

Sources: INEGEI 2006. Instituto Nacional de Ecología 2009

Fixed and area sources

Transportation

waste

Change of soil use and agriculture

Industrial processes

Fugitive emissions

Energy

Shiohara, N., Fernández-Bremauntz, A., Blanco-Jiménez, S. and Yanagisawa, Y., 2005. The commuters’ exposure to volatile chemicals and carcinogenic risk in Mexico City. Atmospheric Environment 39, 3481–3489.

Volatile organic compounds in public transportation in Mexico City

Marr, L. C., Grogan, L. A., Wöhrnschimmel, H., Molina, L. T., Molina, J. M., Smith, T. J., Garshick, E. (2004) Vehicle traffic as a source of particulate polycyclic aromatic hydrocarbon exposure in the Mexico City Metropolitan Area. Environmental Science and Technology (38) pp. 2584-2592

PAHs in public transportation

Assessment of commuter´s personal exposure to air pollutants

Metrobús Insurgentes, Mexico City (2004-2005)

Zero Emissions CorridorEje Central México City (2008-baseline)in progress

BRT Ruiz Cortinez Corridor Monterrey, Nuevo León (2009-baseline)

in progress

CO, PM2.5, PM10 and benzene (before and after Metrobus

2004 2005

Metrobus Insurgentes

Detroit: Batterman et al., 2002Sidney: Duffy and Nelson, 1997Taichung: Kuo et al., 2000Taipei: Chan et al., 1994Boston: Chan et al., 1992Raleigh: Chan, 1991London: Bevan, 1991Mexico: Shiohara et al., 2005 Gómez-Perales et al., 2004 INE/UAMI/GDF-SMA 2009Tula: INE/UAMI 2008Salamanca: INE/IEG/UAMI 2007Monterrey: INE/CTS/APMARN/CETYV 2009Auto Motorbike Minibus Autobus Metro Walking/bike FSM

050

100

150

200

250

Exposure to Benzene

Per

sona

l exp

osur

e (u

g/m

3)

Detroit

MexicoCity

Sidney

Taichung

Taipei

Boston

LosAngeles

Raleigh

Taichung

Taipei

Boston

MexicoCity

MexicoCity

Detroit

MexicoCityMonterrey

MexicoCity

London

Detroit

MexicoCity

TulaMexicoSalamancaMexico

Sidney

05

1015

2025

conc

entr

atio

n at

Fix

ed S

ite M

onito

ring

(FS

M)

stat

ions

, ug/

m3

Benzene indoor levels reported in different cities

PM2.5 personal Exposure reported in the world

Auto Moto Microbús Autobús Metro Caminar/Bici FSM

05

1015

20

Exposición a monóxido de carbono (CO)

ppm

Helsinki

HongKong

Guangzhou

Paris

Amsterdam

Athens

Athens

London Helsinki

Mexico

HongKong

Helsinki

Mexico

HongKong

Guangzhou

Paris

Athens

London Helsinki

Mexico

Guangzhou

Helsinki

HongKong

Paris

Amsterdam

Athens

Athens

London

Mexico

Helsinki: Scotto di Marco et al., 2005Hong Kong: Chan, 1999Paris: Dor et al., 1995Amsterdam: Van Wijnen et al., 1995Athens: Vellopoulou et al., 1998 Duci et al., 2003Guangzhou: Chan et al., 2002Mexico: Gómez-Perales et al., 2002London: Kaur et al., 2005

CO personal Exposure reported in the world

Auto Moto Microbús Autobús Metro Caminar/Bici FSM

050

100

150

200

250

Exposición a Benceno

ppbv

Detroit

Mexico

Sidney

Taichung

Taipei

Boston

LosAngeles

Raleigh

Taichung

Taipei

Boston

MexicoMexico

Detroit

MexicoMexico

London

DetroitSidney

Detroit: Batterman et al., 2002Sidney: Duffy and Nelson, 1997Taichung: Kuo et al., 2000Taipei: Chan et al., 1994Boston: Chan et al., 1992Raleigh: Chan, 1991London: Bevan, 1991Mexico: Shiohara et al., 2005 Gómez-Perales et al., 2002

Benzene personal Exposure reported in the world

Auto Moto Microbús Autobús Metro Caminar/Bici FSM

050

100

150

200

Exposición a PM2.5

ug/m

3

Northampton

Guangzhou

Aberdeen

Boston

London

Mexico

HongKong

London

Mexico

Guangzhou

HongKong

Aberdeen

Boston

London

Mexico

Guangzhou

London

NorthamptonAberdeen

London

Guangzhou: Chan et al., 2002Mexico: Gómez-Perales et al., 2005London: Adams et al., 2001 Adams et al., 2002 Kaur et al., 2005Northampton: Gulliver and Briggs, 2004Aberdeen: Dennekamp et al., 2002Boston: Levy et al., 2002Hong Kong: Chan, 2002

©CENICA

PM2.5 personal Exposure reported in the world

Año Ruta Modo Referencia

1991 Indios Verdes – San Ángel; Tacuba – Pantitlán, Pino Suarez – Xochimilco; La Villa – Auditorio; Marina Nacional – Pantitlán

Auto particular, combi, microbús, autobús, metro, trolé, tren ligero

Fernández-Bremauntz & Ashmore, 1995

2002 Indios Verdes – San Ángel; Tacuba – Pantitlán, La Villa – Auditorio;

Microbús, autobús, metro

Gómez et al., 2004

2003 Indios Verdes – San Ángel; La Villa – Auditorio;

Microbús, autobús Gómez et al., 2007

2004 Indios Verdes – San Ángel Auto particular, Microbús, autobús

Wöhrnschimmel et al., 2008

Studies on personal Exposure reported inMexico

Study objective

• determine reduction in commuters’ exposure to air pollutants that may result from a change from a

conventional bus transport system to a BRT system.

Insurgentes

Methods

• Measurements of PM10, PM2.5, benzene and carbon monoxide invehicle concentrations in conventional public

transport and modern vehicles of a BRT system.

2004

Minibus

2004

Bus

2005

Metrobus

PM10 35 34 55

PM2.5 33 35 51

Benzene 29 29 53

CO 35 34 51

Number of measurements

Results

• Significant reductions in personal exposures inside vehicles of the BRT system between

• 32% and 59% were found for air pollutants associated with vehicular emissions.

• Commuting times dropped by about 20%

Minibus Bus Metrobus

010

020

030

040

050

0

PM10PM2.5

Particulate Matter (ug/m3)

PM10PM2.5

Minibus Bus Metrobus

010

2030

40

68.8

Benzene (ppbv)

Minibus Bus Metrobus0

1020

3040

75.3

Carbon Monoxide (ppm)

Cobenefits Metrobus Insurgentes

– Emissions reductions tons/per year • 144 HCT• 690 NOX

• 2.8 PM• 1.3 SO2

– Health impacts avoided• 6,100 lost days • 600 days of restringed activities • 12 new cases of acute broquitis• 3 premature deaths

– Economic benefits (yearly)• 3 millions USD in health cost• 1.3 m trip time• 12.3 m net benefit

280,000 tons of CO2 eq reductions

Source:INE

Before

• Only “trolebus”• Confined line • Reduccion in traveling

time and emissions • Reduction in personal

exposure to air pollutants • Improvement of urban

Zero emissions Eje Central

• Different routes and different vehicles for public transportation (trolebus, bus, minibus)

• Confined line and use of different lines

• Longer time

Zero Emissions Corridor Eje Central in Mexico City

Field measurements in June-July 2008

Field campaing for personal exposure assessment in Eje central

•Team 1.- Trolebús

•team 2.- mix route

•Team 3.- rotatino mix and trolebus

•team 4.- bus stop

Field campaing for personal exposure assessment in Eje central

Bus stop

Sampler at 1 m height

(to simulate breathing zone)

Field campaing for personal exposure assessment in Eje central

Trolebús Ruta Mixta Automóvil Parabús

05

1015

(ppm

)Monóxido de Carbono

Carbon monoxide

Eje Central Base line for Zero emissions corridor

Microbus (2004)

bus (2004)

Metrobús (2005)

Autobús (1991): 38 ppmMicrobús (1991): 55 ppm

PM2.5

Micro-, Autobús (2004)

Metrobús (2005)

Eje Central Base line for Zero emissions corridor

PM composition*: elemental carbon vs. Organic carbon

Eje Central Base line for Zero emissions corridor

* Subsample

BTX

Trolebús Ruta Mixta Parabús

05

1015

Benceno

Con

c. (

ppbv

)

Trolebús Ruta Mixta Parabús

05

1015

2025

Tolueno

Con

c. (

ppbv

)

Trolebús Ruta Mixta Parabús

05

1015

2025

3035

Xileno

Con

c. (

ppbv

)

Eje Central Base line for Zero emissions corridor

BTX

Trolebús Ruta Mixta Parabús

05

1015

Benceno

Con

c. (

ppbv

)

Trolebús Ruta Mixta Parabús

05

1015

2025

Tolueno

Con

c. (

ppbv

)Trolebús Ruta Mixta Parabús

05

1015

2025

3035

Xileno

Con

c. (

ppbv

)

Microbús (2004)

Autobús (2004)

Metrobús (2005)

Eje Central Base line for Zero emissions corridor

Trolebús Ruta Mixta Automóvil

8010

012

014

016

018

0

Tiempo de recorridoT

iem

po (

min

utos

)

Travel time

Resultados – línea baseEje Central Base line for Zero emissions corridor

Summary

• Trasnportation (public and prive) is an micro-environment with hihg exposure to air pollutants

• Differences in air pollutant concentrations and time being exposed to them result in different communter`s exposure

• Demonstrated reductions in communter`s exposore to air pollutants with Metrobus Insurgente

• Potential to use this data and transform into indicators

• Personal exposure assessment studies could be used to support the implemntation of BRTs but ...

– questions should be asked – Critical mass and analytical infraestructure need to be expanded– Communicate what is already available

• Potential to share experiences and learn from mistakes

• Assertive communication

Conclusions

• BRT systems have the potential to reduce in-vehicle concentrations of air pollutants in comparison to conventional transport modes.

• The additional reduction of commuting times further decreases total exposure and thus the health impact of

commuting.

• BRT systems contribute to increased quality of life of public transport users.

Next steps

• Field campaign at the Zero Emissions corridor

• Field campaign at the Monterrey Corridor

• Identify needs of information – Other cities – Other partners

Gracias

bcardena@ine.gob.mx

www.ine.gob.mx