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Connecting Air Quality Research, Risk Assessment and Policy:

U.S. Air Quality Management

John Vandenberg, PhD

Director

Health and Environmental Effects Assessment Division

Center for Public Health and Environmental Assessment

U.S. Environmental Protection Agency

Research Triangle Park, NC 27711

Vandenberg.john@epa.gov

Disclaimer: These views are those of the author and do not represent US EPA policy.

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Goal: Air Quality Standards

Environmental Condition:Monitoring/ModelingEmissions Inventory

Enforcement/Compliance

State Planning:Stationary and Mobile

Sources

Track Progress

Framework for Air Quality Management

Effects/Exposure Research

Atmos Sciences/Engineering Research

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Approaches to Air Quality Management

1. Ambient Standards (Criteria Air Pollutants)

2. Emission Standards (Hazardous Air Pollutants)

3.Market-Based(Acidification and Eutrophication: another day)

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“Criteria” Air Pollutants

• 6 criteria pollutants:

– Ground-level = tropospheric ozone (O3)

– Particulate matter (PM2.5 and PM10)

– Lead (Pb)

– Sulfur dioxide (SO2)

– Nitrogen dioxide (NO2)

– Carbon monoxide (CO)

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Number of People Living in Areas with Air Quality Concentrations Above the Level of the Primary National

Ambient Air Quality Standards (NAAQS) in 2019

http://epa.gov/airtrends/aqtrends.html

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Approach for Evaluation of the Scientific Evidence

• Organize relevant literature for broad outcome categories

• Evaluate studies, characterize results, extract relevant data

• Integrate evidence across disciplines for outcome categories

• Develop health and welfare causality determinations using established framework described in the Preamble

• Synthesize evidence for populations potentially at increased risk (health only)

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Illustrative Example: Evidence Integration for Health

Air Pollution Health Effects Pyramid

Severity ofeffect

proportion of population affected

Mortality

Hospitaladmissions

Emergency room visitsPhysician office visits

Reduced physical performanceMedication use

Respiratory symptomsImpaired lung function

Sub-clinical (subtle) effects

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Figure 3-1 Potential biological pathways for respiratory effects following short-term ozone exposure.

EPA/600/R 19/093April 2020www.epa.gov/isa

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Figure ES-3 Cross-study comparisons of mean decrements in ozone-induced forced expiratory volume in 1 second(FEV1) in young, healthy adults following 6.6 hours of exposure to ozone.

EPA/600/R 19/093April 2020www.epa.gov/isa

Percent increase in respiratory-related hospital admission (HA) and emergency

department (ED) visits

Figure 6-19, page 6-153 Ozone ISA 2013 http://cfpub.epa.gov/ncea/isa/recordisplay.cfm?deid=247492

Black: all yearRed: summer onlyBlue: winter only

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Figure ES-2 Causality determinations for health effects of short- and long-term exposure to ozone.

EPA/600/R 19/093April 23, 2020www.epa.gov/isa

• Ozone primary standard: Decision in October 2015 to lower standard level from 0.075 ppm to 0.070 ppm– Secondary standard set equal to the Primary std.

• Final decision December 2020– Retain 2015 standards

Ozone NAAQS

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Summary: Criteria Air Pollutants

• Goal: National Ambient Air Quality Standards

• Management: ambient standards set to protect with an adequate margin of safety– Numerous and diverse stationary and mobile sources– Cost not considered in setting standards– Cost can be considered in implementing control programs

• States responsible to develop State Implementation Plans: many tools in the toolbox

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Approach 2

Emission Standards:Hazardous Air Pollutants

(aka Air Toxics)

Clean Air Act

• Hazardous air pollutants:– “increase in mortality or serious irreversible or

reversible, incapacitating illness”

• List Pollutants:– “for which the Administrator intends to

develop emissions standards”

• Set Standards:– “to protect public health with an ample margin

of safety”

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The Clean Air Act Amendments of 1990 -List of Hazardous Air Pollutants

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Numerous Biologic EndpointsNumerous Biologic Endpoints

• Mutations

• DNA damage

• Etc.

• Reproductive,

• developmental, neurological disorders

• Immunologic effects

• Acute effects (edema, CNS depression)

• Various other systemic effects (e.g., liver, kidney, lung damage)

Non-Cancer Cancer

Multiple Adverse Endpoints

Uncontrolled Growth of Cells

NASA Graphic

Inte

ract

ion

with

H

AP

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Planning and ScopingExposure AssessmentExposure Assessment Toxicity Assessment

Risk Characterization

Quantitative and Qualitative Expressions of Risk/Uncertainty

POPULATION CHARACTERISTICS

Measures of Exposure

CHEMICALCONCENTRATIONS

Air, Soil, Water, Food(monitor/model)

Air Toxics Risk Assessment Process

Dose/ Response

Assessment

Y

X

Chemical Release SOURCES

FATE AND TRANSPORT ANALYSISHazard Identification

EXPOSURE information

DOSE/RESPONSE information

SOURCE IDENTIFICATION

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Risk isacceptable withample margin

No furtheraction needed

Risk

1x10-6

Risk may beAcceptable

Look at Health Issues

Then consider costs/technical feasibilitybefore deciding if

emissions reductionsare needed

Risk is unacceptable

Take actionto reduce risks

Can only consider health

1x10-4

Risk Ranges

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Summary: Hazardous Air Pollutants

• Pollutants listed by Congress• Source categories• National Emission Standards for Hazardous

Air Pollutants (NESHAP) • Apply technology (e.g., limit to lb/yr)

– Maximum Achievable Control Technology• Evaluate residual risks (e.g., limit risks)

– Ample margin of safety

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“Across the Federal government, the rules with the highest estimated benefits as well as the highest estimated costs come from the Environmental Protection Agency and in particular its Office of Air and Radiation. Specifically, EPA rules account for 71 percent to 80 percent of the monetized benefits and 55 percent to 64 percent of the monetized costs. Of these, rules that have a significant aim to improve air quality account for over 95 percent of the benefits of EPA rules…. Importantly, the large estimated benefits of EPA rules issued pursuant to the CAA are mostly attributable to the reduction in public exposure to fine particulate matter (referred to in many contexts as PM2.5). (emphasis added)

2017 Report to Congress on the Benefits and Costs of Federal Regulations and Agency Compliance with

the Unfunded Mandates Reform Act

https://www.whitehouse.gov/wp-content/uploads/2019/12/2019-CATS-5885-REV_DOC-2017Cost_BenefitReport11_18_2019.docx.pdf

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Connecting Air Quality Research, Risk Assessment and Policy:

U.S. Air Quality Management

John Vandenberg, PhD

Director

Health and Environmental Effects Assessment Division

Center for Public Health and Environmental Assessment

U.S. Environmental Protection Agency

Research Triangle Park, NC 27711

Vandenberg.john@epa.gov

John.Vandenberg@duke.edu