Environmental Health Risks: The Health Effects of Ozone Environmental Health Risks: The Health Effects of Ozone

Healthy Carolinians Conference September 29, 2010

Susan Lyon StoneUS EPA Office of Air Quality Planning and Standards

stone.susan@epa.gov

Healthy Carolinians Conference September 29, 2010

Susan Lyon StoneUS EPA Office of Air Quality Planning and Standards

stone.susan@epa.gov

Review Process for StandardsReview Process for Standards

Scientific studies on health and environmental effects

EPA Integrated Science Assessment (ISA)

EPA Risk/Exposure Assessment (REA) + Policy Assessment (PA)

Scientific peer review of published studies

Reviews by CASAC and the public

Reviews by CASAC and the public

Public hearings and comments on proposals

Proposed Decision

Final Decision

Ozone final decision around the end October 2010

Human LungHuman Lung

• Air conducting– Trachea– Bronchi– Bronchioles

• Gas exchange– Respiratory

bronchioles– Alveoli

• Air conducting– Trachea– Bronchi– Bronchioles

• Gas exchange– Respiratory

bronchioles– Alveoli

Ozone Irritates AirwaysOzone Irritates AirwaysOzone Irritates AirwaysOzone Irritates Airways

• Symptoms– Cough– Sore or scratchy throat– Pain with deep breath– Fatigue

• Rapid onset• Asthma symptoms - greater in people

with asthma, also occur in people without asthma

• Symptoms– Cough– Sore or scratchy throat– Pain with deep breath– Fatigue

• Rapid onset• Asthma symptoms - greater in people

with asthma, also occur in people without asthma

Ozone Reduces Lung FunctionOzone Reduces Lung FunctionOzone Reduces Lung FunctionOzone Reduces Lung Function

BASELINEBASELINE 2HR2HR 4HR4HR

FE

V1,

% C

HA

NG

EF

EV

1, %

CH

AN

GE

-60-60

-40-40

-20-20

00

M-10

M-1c

Ozone Causes InflammationOzone Causes InflammationOzone Causes InflammationOzone Causes Inflammation

• Ozone reacts completely in surface layer - forms reactive oxygen molecules

• Increases permeability of cells that line airways• Influx of white blood cells and proteins • Damages cells that line the airways• Effect is greater 24 hours after exposure• Increases airway reactivity• Concern about repeated exposures

• Ozone reacts completely in surface layer - forms reactive oxygen molecules

• Increases permeability of cells that line airways• Influx of white blood cells and proteins • Damages cells that line the airways• Effect is greater 24 hours after exposure• Increases airway reactivity• Concern about repeated exposures

Respiratory Hospital Admissions by Respiratory Hospital Admissions by Daily MaximumDaily Maximum Ozone Level, Lagged One Day

Respiratory Hospital Admissions by Respiratory Hospital Admissions by Daily MaximumDaily Maximum Ozone Level, Lagged One Day

114

112

110

108

106

104

102

114

112

110

108

106

104

102

Ozone concentration (ppm)Ozone concentration (ppm)

Res

pir

ato

ry A

dm

issi

on

sR

esp

irat

ory

Ad

mis

sio

ns

.01 .02 .03 .04 .05 .06 .07 .08 .09 .1.01 .02 .03 .04 .05 .06 .07 .08 .09 .1

D-8a

(Burnett et al, 1994)(Burnett et al, 1994)

California Children’s Health StudyCalifornia Children’s Health Study

CHS: Ozone and School AbsencesCHS: Ozone and School Absences

• 20 ppb increase in O3 associated with an 83% increase in school absences for acute respiratory disease (Gilliland et al., 2001)

• Large economic impact of pollution-related school absences (Hall and Lurmann, 2003)

• 20 ppb increase in O3 associated with an 83% increase in school absences for acute respiratory disease (Gilliland et al., 2001)

• Large economic impact of pollution-related school absences (Hall and Lurmann, 2003)

CHS: Ozone and New-onset AsthmaCHS: Ozone and New-onset Asthma

McConnell et al., 2002McConnell et al., 2002

Evidence from 2008 Review of Ozone StandardEvidence from 2008 Review of Ozone Standard

• Evidence of lung function decrements and symptoms at 0.060 ppm in healthy people

• New information about physiological bases of increased sensitivity of people with asthma– Larger decreases lung function– Increased magnitude and duration airway responsiveness– Increased inflammatory responses– Different cellular responses

• Epidemiological studies show:– Increased symptoms and medication use in asthmatic

children– School absences– Emergency room visits and hospital admissions– Premature mortality

• Evidence of lung function decrements and symptoms at 0.060 ppm in healthy people

• New information about physiological bases of increased sensitivity of people with asthma– Larger decreases lung function– Increased magnitude and duration airway responsiveness– Increased inflammatory responses– Different cellular responses

• Epidemiological studies show:– Increased symptoms and medication use in asthmatic

children– School absences– Emergency room visits and hospital admissions– Premature mortality

Sensitive Groups for OzoneSensitive Groups for Ozone

• People with lung disease• Children• Older adults• People who are active outdoors

• People with lung disease• Children• Older adults• People who are active outdoors

Air Quality IndexAir Quality IndexAir Quality IndexAir Quality Index

Descriptors Cautionary StatementGood

0 – 50

No message

Moderate

51 – 100

Unusually sensitive individuals

Unhealthy for Sensitive Groups

101 - 150

Identifiable groups at risk - different groups for different pollutants

Unhealthy

151 - 200

General public at risk; sensitive groups at greater risk

Very Unhealthy

201 - 300

General public at greater risk; sensitive groups at greatest risk

Air Quality IndexAir Quality Index

• Pollutant-specific health effects and cautionary statements Pollutant-specific health effects and cautionary statements address question “who will be affected”address question “who will be affected”

Dose = Concentration x Ventilation rate x TimeDose = Concentration x Ventilation rate x TimeC - be active outdoors when air quality is betterC - be active outdoors when air quality is better

V - take it easier when active outdoorsV - take it easier when active outdoors

T - spend less time being active outdoorsT - spend less time being active outdoors

• Reduce these factors (C,V,T) to reduce dose

• Pay attention to symptoms

• People with asthma – follow asthma action plan

• Coaches – rotate players frequently

• People with heart disease – check with your doctor

Physical Activity and Health

Activity

Ris

k o

f “D

i se a

se”

Prevention of Weight Gain

Diabetes Mellitus

Musculoskeletal InjuryFunctional Health Status

CHD

Stroke

Osteoporosis

Source: HW Kohl, University of Texas School of Public Health

Effectiveness of the AQI

• Effectiveness has been measured many ways– Surveys: What people say

• Behavior• Behavior and demographics (EPA, BRFSS)

– Activity diaries: What people do (RTI)– Health studies: Changes in health outcomes

• Surveys– Large proportion report awareness (50 -75%)– Of those about 50% report taking action– People of older age, fair or poor health status, and females

more likely to reduce exposure (EPA Health and Aging Survey)

– Recommendation by healthcare provider much more likely to reduce exposure (Wen et al., 2009 - 2005 BRFSS Survey)

• Odds ratio of changing behavior based on media reports = 2.16 (95% CI: 1.61, 2.90)

• Percent change in behavior based on alerts with professional advice = 50.7%; without professional advice = 14.2%

Determinants of Parents’ Ozone Forecast Monitoring

Parents of asthmatics more likely to report checking AQI forecast frequently

More serious asthma = more frequent checking

More children = less frequent checking

White parent = less frequent checking

Source: Carol Mansfield, RTI

Summary of results on time outdoors

Evidence that Air pollution sensitive asthmatics

reduce time outdoors on code red days (based on daily diaries)

30+ minute reduction in time outdoors on Code Red day relative to non-Code Red day

Source: Carol Mansfield, RTI

Air Pollution Sensitive vs. Not Air Pollution Sensitive Asthmatics

0

20

40

60

80

100

6 AM 7 AM 8 AM 9 AM 10AM

11AM

12 PM 1 PM 2 PM 3 PM 4 PM 5 PM 6 PM 7 PM

Time spent (minutes)

APSA - Code Red Days APSA - Code Green Days

Non-APSA - Code Red Days Non-APSA - Code Green Days

Source: Carol Mansfield, RTI

Health Studies

• Los Angeles study: Neidell and Kinney (2010)

– Asthma hospital admissions 1989-1997

– Control for air quality forecasts to account for avoidance behavior

– Accounting for behavior leads to significantly larger effects estimates; however there is a cost to behavior

• DFW: Carls U of MI dissertation– Forecasts protective of health and

alter relationships between asthma exacerbations and air quality

– Previous day O3 alerts were protective for high morbidity outcomes (hospital/ER); but not for the low morbidity outcomes (outpatient visits, medication use)

All 5-19 ≥ 65

No control 0.017 0.016 0.022

With control 0.027 0.037 0.037

Difference 1.59** 2.31** 1.36*

Increase asthma hospitalizations per 10 ppb O3 - Neidell and Kinney (2010)

**P<0.01; *P<0.10

No control 7.0%

Control 11.6%*

Orange Alert - 14.1%*

Red Alert -19.9%

Change in asthma hospitalizations per 20 ppb O3 - Carls (2010)

*P<0.05

AIRNow.govAIRNow.gov

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Web cams

AQI Curriculum for Children and StudentsAQI Curriculum for Children and Students

Colorful lessons and games Colorful lessons and games for children and studentsfor children and students

Children’s BookChildren’s Book

AQI BookletAQI Booklet

Ozone and Your HealthOzone and Your Health

Downloadable FactsheetsDownloadable Factsheets

Ozone Web Course Ozone Web Course for Health Care Providersfor Health Care Providers

Ozone Web Course Ozone Web Course for Health Care Providersfor Health Care Providers

MedicalMedical

PosterPoster

Social NetworkingSocial Networking

• Facebook:Twitter:

http://twitter.com/airnow http://www.facebook.com/airnow

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