Visualizing Vulnerabilities and Impacts in Communities

Photo: GreenAction

Rachel Morello-FroschUC Berkeley, Department of Environmental Science,

Policy & Management and School of Public Health

Collaborators: Manuel Pastor, University of Southern California, Dept. of GeographyJames Sadd, Occidental College, Dept. of Environmental Sciences

CAPCOA – September 2007

Work supported by California Air Resources Board &US EPA, Region 9, RARE Grant

Science of Environmental Justice - Overview Influence of environmental justice framework on

environmental health science and regulation

Cumulative impact Community & individual vulnerability/resilience

Synergies between these factors that shape environmental health disparities

Segregation as a case study of area-level inequality in pollutant exposures

Birth outcomes as potential area for examining synergies between stressors and pollution exposures

Tomorrow’s Session: Mapping indicators of impact/vulnerability (M. Pastor)

Areas of Scientific Contention in Environmental Justice

EJ advocates have pushed researchers and regulators to operationalize the dynamics of: Cumulative impact from multiple environmental hazards

exposures faced by communities of color and the poor where they live, work, and play.

Community vulnerability to the adverse health effects of pollutants due to simultaneous exposures to psycho-social and physical stressors (e.g. poverty, material deprivation, malnutrition, discrimination)

Regulatory agency response: California Environmental Protection Agency Environmental Justice

Action Plan U.S. EPA Framework for Cumulative Risk Assessment

DeFur et al. (2007) Vulnerability as a Function of Individual and Group Resources in Cumulative Risk Assessment, Environmental Health Perspectives 115(5)

Segregation, Social Inequality, and Environmental (In)Justice

Aerial shot of fenceline community along Chevron Refinery in Richmond, CA

Chevron

General Chemical

Kinder Morgan Liquids Terminal

Tosco DistributionBritish Petroleum

National Gypsum

Levin Terminal

California OilsBio-RadLaboratory

Selected Pollution Sources Near Community

Richmond Pkwy

Chevron Refinery Fire – January 2007

Photos: KCBS News

Segregation, Social Inequality, and Environmental (In)Justice

Links spatial inequality and political economy of environmental health by asking: How do legacies of discrimination shape current spatial distributions

of pollution sources among diverse communities? Are observed pollution – health associations modified by measures of

social inequality and material deprivation? Do segregation patterns affect diverse communities differently?

Promotes interdisciplinary approaches Links sociology, city planning, policy and environmental health Moves inquiry upstream with policy-relevant measures of institutional

& socioeconomic drivers of environmental health disparities Changes scale of inquiry– regional focus:

Decisions about economic and industrial development, land use, and transportation tend to be made at a regional or metro level

Basics of Segregation

Describes spatial separation of people by race and (less often) by class

Applies to various contexts Residential Occupational Educational

Measurement Used to characterize racial inequality within a metro area or region Often focuses on dyadic comparisons

(e.g. Black v. White) Can also be considered in context of racial diversity

(e.g. multi-group segregation)

Community-level Impact Individual-level Impact

Community-level Stressors/Buffers

Built EnvironmentLand Use/Zoning

Traffic DensityHousing Quality

Social EnvironmentCivic Engagement/Political Empowerment

Poverty ConcentrationAccess to Services

Food SecurityRegulatory Enforcement Activities

Neighborhood QualitySocial Capital

Individual-level Stressors/Buffers

Social supportPoverty/SES

Working ConditionsHealth Care Access

Diet/Nutritional StatusPsycho-social Stress

Health BehaviorsReproductive Events

PollutantSource

Location

Area LevelContamination

ExposureInternal

DoseHealthEffect

Industrial Facility/Transportation

Corridor

Chemicals Emitted

Indoor/Outdoor Pollution Levels

ChemicalBody Burden Birth Outcome

Response &Resilience

DetoxificationCapacity/DNA

Repair

Ability to Recover

Co-Morbidity/Mortality

How Community and Individual Stressors/Buffers Combine to Shape Exposures and Susceptibility to Environmental Hazards

(Morello-Frosch & Shenassa, EHP, 2006)

Individual Immune Response/Weathering

Chronic Individual Stress

Segregation Measure: Generalized Index of Dissimilarity

Measures segregation across several demographic groups within a metropolitan statistical area (MSA)

Indicator of Spatial ‘Uneveness’

Index varies from 0 (no segregation) to 1 (completely segregated).

even uneven

# people who must move from one census tract to another to attain racial/ethnic balance within a metro area

maximum value of numerator if each racial/ethnic group were completely segregated

Dm =

high

low / moderate

extreme

segregation level

Border States

West Coast

South

regional group

Midwest

Northeast

Mountains & Plains

Multi-Group Racial/Ethnic Segregation in the United States

U.S. EPA’s National Air Toxics Assessment (NATA)

Gaussian dispersion model estimates long-term annual average outdoor concentrations for 1996 of 32 air toxics and diesel particulates for each census tract.

The model includes mobile and stationary emissions sources:

Manufacturing (point and area)e.g., refineries, chrome plating

Non-Manufacturing (point and area)e.g., utilities, hospitals, dry cleaners

Mobile (on road and off road)e.g., cars, trucks, air craft, agricultural equipment

Air pollutant concentration estimates allocated to census tract centroids.

Estimating Cancer Risk

Lifetime cancer risk calculated for each pollutant with toxicity information:

Rij = Cij * IURj

Rij = individual lifetime cancer risk from pollutant j in census tract i.

Cij = concentration of HAP j in ug/m3 in census tract i.

IUR = Inhalation Unit Risk: cancer potency associated with continuous lifetime exposure to pollutant j in (ug/m3)-1

Risks summed across pollutants

estimated cancer risk by source,and by racial/ ethnic residential segregation,

continental U. S. metropolitan areas

0

200

400

600

800

1000

all metropolitan areas(n=309)

0.16 to 0.39 0.40 to 0.59 0.60 to 0.82

esti

mat

ed li

feti

me

canc

er r

isk

from

am

bien

t ai

r po

lluta

nts,

1996

NAT

A es

tim

ates

(pe

r m

illio

n re

side

nts)

mobile non-road sources

mobile on-road sources

area sources

point sources

background

low/moderate high extreme

Segregation

Est

imat

ed L

ifetim

e C

ance

r R

isk

(per

mill

ion

resi

dent

s)

small emitters

mobile on-road sources

background

industrial facilities

mobile non-road sources

Estimated cancer risk associated with ambient air toxics by race/ethnicity and racial/ethnic residential segregation,

continental United States metropolitan areas

0

500

1000

1500

2000all

metr

opolit

an

are

as

(n=

30

9)

low

/m

odera

te

hig

h

extr

em

e

segregation (multi-group dissimilarity index)

est

imate

d lifeti

me c

ance

r ri

sk(p

er

mill

ion r

esi

dents

)

totalpopulation

non-HispanicWhites

non-HispanicBlacks

Hispanics

AmericanIndians andAlaska NativesAsians andPacificIslanders

Estimated cancer risk associated with ambient air toxics by race/ethnicity and poverty status,

continental Unites States metropolitan areas

0

500

1000

1500

2000

inco

me less

than p

overt

y

inco

me n

ear

povert

y

inco

me

gre

ate

r th

an

twic

e p

overt

y

est

imate

d lifeti

me c

ance

r ri

sk(p

er

mill

ion r

esi

dents

)

totalpopulation

non-HispanicWhites

non-HispanicBlacks

Hispanics

AmericanIndians andAlaska NativesAsians andPacificIslanders

Relative estimated lifetime cancer incidence associated with ambient air toxics continental United States metropolitan areas (adjusted model)

model adjusted for state regional grouping; metropolitan area population size; county voter turnout; census tract population density, poverty rate, and material deprivation

highly segregated extremely segregated

hazard ratio

hazard ratio

total population 1.04 ( 1.01 - 1.07 ) 1.32 ( 1.28 - 1.36 )

non-Hispanic Whites 1.04 ( 1.01 - 1.08 ) 1.28 ( 1.24 - 1.33 )

non-Hispanic Blacks 1.09 ( 0.98 - 1.21 ) 1.38 ( 1.24 - 1.53 )

Hispanics (all races) 1.09 ( 1.01 - 1.17 ) 1.74 ( 1.61 - 1.88 )

non-Hispanic American Indians & Alaska Natives 1.02 ( 0.77 - 1.35 ) 1.21 ( 0.90 - 1.64 )

non-Hispanic Asians & Pacific Islanders 1.10 ( 0.97 - 1.24 ) 1.32 ( 1.16 - 1.51 )*Risk Ratios use low segregation as reference group

95% conf. interval

95% conf. interval

1.0

1.2

1.4

1.6

1.8

2.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

hazard

rati

o

Individual and area-level drivers of environmental health inequalities – birth outcomes and air pollution (course PM)

Mural Photo: R. Morello-Frosch

Individual stressors can:

Affect birth outcomes directly (well studied) e.g., health behaviors, inter-pregnancy interval, access to adequate

health care, poverty, discrimination (using race as a crude proxy)

Enhance individual susceptibility to the toxic effects of pollutants (not extensively studied)

Bell et al., EHP, 2007: effect modification by race for association between PM2.5 and decrease in birth weight among black versus white mothers

Place-based stressors can: Affect birth outcomes directly (fairly well studied)

e.g. neighborhood poverty, material deprivation, income inequality, and segregation

Enhance susceptibility to the toxic effects of pollutants (not extensively studied)

Ponce et al., EHP, 2005: effect modification with neighborhood disadvantage for association between traffic density and risk of pre-term birth during winter season

Effect modification: Ponce et al EHP (2005)

DWTD and preterm deliveryLos Angeles 1994-1996

0.2

0.6

1

1.4

1.8

Summer Winter Summer Winter

OR

(95%

CI)

Low Neighborhood SES

High Neighborhood SES

Relationship between PMcoarse and birth weight

California Births from 1996-2003 Air pollution estimates for each live birth in the

dataset, according to the mother's residence at the time of birth within 2 kilometers of a CalAIRS monitor

Developed single and multiple pollutant models to assess air pollution effects on birth weight

Used individual and area-level SES measures to examine confounding and effect modification

Possible Biological Mechanisms - PM

Particulate matter

Altered immunity

Endocrine disruption

InfectionPreterm labor,

IUGR

Miscarriage, preterm labor

Lower progesterone

production

Th1 dominanceSlowed

embryonic development

B. Ritz, ISEE 2007

Change in birthweight, per 10 μg/m3 of coarse particulate matter,assessed within 2km, by quartiles of exposure

-60

-50

-40

-30

-20

-10

0

10

0 - 2

5%

25 -

50%

50 -

75%

75 -

100%

chan

ge in

bir

thw

eigh

t per

10μ

m/m3 o

f PM

coa

rse

Change in birthweight, per 10 μg/m3 increase in coarse particulate matter(within 2km distance of monitor)

-60.0

-50.0

-40.0

-30.0

-20.0

-10.0

0.0

10.0

chan

ge i

n bi

rthw

eigh

t in

gra

ms

per

10μ

m/m3

of

PM

co

arse

Individual factors = maternal race, marital status, education, age, parity, gestational age, infant sex, prenatal care, pregnancy risk factors, season and year of birth.

Neighborhood factors = unemployment, education, poverty, home ownership

N= 2,579,123 births

Change in birthweight, per 10 μg/m3 increase of coarse particulate matter by race/ethnicity

-60

-50

-40

-30

-20

-10

0

10

tota

l pop

ulat

ion

(PM

cour

se)

His

pani

cs (

PMco

urse

)

Afr

ican

Am

eric

an (

PMco

urse

)

Asi

ans

& P

acif

ic I

slan

ders

(PM

cour

se)

Whi

tes

(PM

cour

se)

Bel

l et a

l 200

7 A

f. A

m (

PM2.

5)

Bel

l et a

l 200

7 W

hite

s (P

M 2

.5)

chan

ge in

bir

thw

eigh

t per

10μ

m/m3 o

f P

M c

oars

e

Change in birthweight, per 10 μg/m3 of coarse particulate matter,by county income inequality

-60

-50

-40

-30

-20

-10

0

10

all c

ount

ies

med

ium

/low

Gin

i cou

ntie

s

(0.2

9 -

0.34

)

high

Gin

i cou

ntie

s

(0.3

4 -

0.36

)

chan

ge in

bir

thw

eigh

t per

10μ

m/m3 o

f PM

coa

rse

Implications for future work Evidence suggests spatial forms of social

inequality are associated with: Worse environmental quality across demographic lines Increased racial inequalities in pollution burdens

Indicators of social inequality and discrimination may reveal enhanced pollution/health outcome relationships in certain populations E.g. individuals or communities faced with chronic

socioeconomic stressors may be at higher risk of adverse health consequences of pollution exposures

Implications (cont.)

Macro-level Questions : Development of policy-relevant surrogates for

measures of impact and vulnerability Traffic/truck data as a surrogate for pollution

exposures of concern Area measures of social inequality, access to health

care as indicators of neighborhood vulnerability Examine different geographic scales that may be

more relevant for regulation and policy? E.g. zoning and facility siting decisions affect pollution

stream distributions among diverse communities and tend to operate regionally

Intervention points would focus on -- land use planning, industrial and transportation development

Four Policy/Regulatory Principles Consider cumulative impacts – move beyond facility-

by-facility regulation to holistic approaches that consider the community as the basic unit of analysis

Take into account social vulnerability – consider neighborhood stressors together with exposures/risk in regulatory programs and decision-making

Promote community participation – assessments of cumulative impact and vulnerability must involve input from and ongoing engagement of community residents.

Take meaningful action – precaution dictates that policy-relevant indicators of impact and vulnerability should guide decision-making in order to protect health and eliminate environmental health inequalities

What Is To Be Done?