Georgia 2008

Air Quality & Climate Summit

Communicating Risk:

How Should We Monitor Air Quality and Respond Appropriately?

Gerry Teague

We all agree that bad air is bad…..

BUT,

Are health risks the same for everyone?

Is there a minimum “safe” exposure level?

Aren’t you safe if you don’t live downtown?

Why the Health Message is Lost:Flaws in Current Air Pollution Policy

• Not consistent among agencies

• Shaped by political and commercial agendas

• Emphasis on public vs. personal exposure

Communicating Exposure

• When you can see bad air you hear about it!

• Vehicular emissions – personal aspects- micro-effects of busy thoroughfares - school buses

• Effects of age (children)

• Effects of activity (athletes)

The Atlanta Journal-ConstitutionMarch 2, 2007

Controlled Fire Leaves Atlanta AreaWheezing….

400 m

EC: 9 times higher at roadOC: 1.4 times higher at road

0

2

4

6

8

10

12

EC OC WSOC

Expressway vs GIT

ExpresswayGIT

Co

ncen

trati

on

, µ

gC

/m3

Two Filters10 am -10 pm

4.5

0.5

11

7.8

4.74.3

(Soot) (Water-Soluble)

Personal Exposure – How near a freeway issafe?

Courtesy of Rodney Weber, PhD, Ga Inst. Tech

The Dilemma of School Buses:What is Good for the Air Ain’t Good for You

Children who ride in school buses are exposedto levels of diesel soot high enough to result in anan additional 23-46 cancer cases per millionchildren exposed.

National Resources Defense Council,Coalition for Clean Air, UC Berkeley

Zone Concept: Children InhaleMore Indoor Irritants

2 ft.

Adult6 ft.

ChildBreathingZones

Toddlers

Disturbed Irritants,

Particles, andAllergens

Disturbed Irritants,

Particles, andAllergens

Athletes Hyperventilate Bad Air

• The lung is more exposed to airborne pollutants:

Rest Exercise Minute ventilation 5 40 - 80 (L/min)

• Athletes tend to mouth breath, and bypass the nasal filter.

Adverse Health Effects of Air Pollution

Excellent evidence: - exacerbations of asthma - increased heart attack and stroke

Fair to good evidence: - exacerbations of other chronic lung diseases (COPD, cystic fibrosis) - lung cancer - reduced lung growth in children

Growing evidence: - environmental genomics - effects of micro-climates - risks in athletes

The Challenge: Bad Air is A Soup

• Ozone (O3)

• Nitrogen dioxide (NO2)

• Sulfur dioxide (SO2)

• Carbon monoxide (CO)

• Lead (Pb)

• Particulate matter (PM2.5 and PM10)

Old and Young

Young children whose lungs are developing, and seniors and people with chronic disorders of the lungs

and heart are more sensitive.

SensitiveIndividuals

Individuals with asthma, chronic bronchitis,

emphysema, cystic fibrosis, and known cardiac conditions

should take extra precautions during air pollution episodes.

Healthy People

Everyone who works outside or engages in vigorous outdoor exercise for prolonged periods during smog episodes is at increased risk of

experiencing adverse health effects caused by smog.

Dose = (Pollutant Concentration) X (Breathing Rate) X (Time Engaged in Activity)

Another challenge:humans are complicated!

Levelof Risk:

Courtesy of MichaelChang

0 50 150Air Quality Index

Risk of symptoms

Symptom Risk and the AQI:Does Not Account for Human Variation

Does not take into account:- genetic susceptibility- antioxidant status- nutrition

Bad Air Myths

• A person is protected from air pollution if they live in the suburbs or on a farm.

• A healthy person is not threatened by bad air.

• Indoor air is safer than outdoor air during a pollution event.

• A “safe” level of air pollution has been identified.

What I Tell My Patient’s Parents

• Pay attention to the air quality report.

• If your child takes the school bus, insist on a “retro-fitted” one.

• On a bad air day avoid outdoors exercise between 4:00 and 6:00 pm.

• Live and go to school away from busy traffic corridors if you can.

• Don’t get ripped off by the indoor air purification industry.