Renee Sharp

Bill Walker
ENVIRONMENTAL WORKING GROUP 2

Acknowledgments

Thanks to Joann Lu and Samantha Scola of the California Air Resources Board

and Leland Deck of ABT Associates for help with data. Thanks to Kent

Bransford, Bob Gould, Amy Kyle and Gina Solomon, who reviewed and

commented on the report. Thanks to Liza West and her staff at EMS West for

help with press materials and release of the report. At EWG, thanks to Richard

Wiles and Jane Houlihan, who read many drafts and made many helpful

suggestions, and to Tim Greenleaf, who designed the report and produced

the graphics.

This report was primarily made possible by grants from the Steven and Michelle

Kirsch Foundation and the As You Sow Foundation. Additional support for

EWG’s air pollution work in California comes from The California Wellness

Foundation, the Richard and Rhoda Goldman Fund, the Clarence T. Heller

Charitable Foundation and the Homeland Foundation. Opinions expressed

are those of the authors, who are responsible for any errors of fact of

misinterpretation.

Environmental Working Group

EWG is a nonprofit research and advocacy organization with offices in

Washington, D.C., and Oakland, CA. EWG uses information technology to

conduct research and inform the public on a range of environmental issues,

particularly those affecting public health.

To order a copy

Copies of this report may be ordered from EWG’s Washington office for $20 each plus

$3 for postage and handling. (DC residents add 6 percent sales tax.) Send orders to

1718 Connecticut Ave. NW, Suite 600, Washington DC 20009

On the Internet

This report and other EWG publications are available online at www.ewg.org.
ENVIRONMENTAL WORKING GROUP 3

Particle Civics

Table of Contents

Chapter 1: A Life and Death Decision............................................... Page 7

Chapter 2: California’s Particulate Problem..................................... Page 17

Chapter 3: Air Pollution, Illness, and Death.................................... Page 25

Chapter 4: Particle Civics.................................................................. Page 31

Chapter 5: Who’s Against Clean Air?............................................... Page 37
ENVIRONMENTAL WORKING GROUP 4
ENVIRONMENTAL WORKING GROUP 5

Particle Civics

Executive Summary

Airborne soot and dust, technically known as particulate air pollution, causes

or contributes to the deaths of more Californians than car accidents, murder

and AIDS combined. State health officials are proposing new air pollution

rules that could save or extend more than 6,500 lives a year, but the proposal

faces strong and well-financed opposition from major oil companies and

automakers.

In California, respiratory illnesses caused or made worse by airborne particulate

matter (PM) are responsible for 9,300 deaths, 16,000 hospital visits, 600,000

asthma attacks and five million lost work days each year. By saving lives and

preventing illnesses, tougher standards could save more than half a billion

dollars a year.

In recent years, hundreds of studies worldwide have shown that PM pollution

kills people. Both short- and long-term exposure to particulate pollution at

levels lower than the levels currently experienced by millions of California

residents can cause death. The proposed new PM standards are the first new

regulations developed in response to a landmark 1999 state law requiring that

air pollution standards must be adequate to protect children’s health.

Statewide, total PM emissions are on the rise, and the great majority of

Californians are exposed to potentially harmful levels. The worst particulate

pollution in the state is found in Imperial County. But far more Californians

are affected by the severe problems in the South Coast Air Basin, covering

greater Los Angeles, which has the highest PM levels of any U.S. metro area,

and the eight-county San Joaquin Valley, which is among the six worst areas

in the nation. EWG estimates that the proposed new standards could save

more than 4,200 lives a year in the South Coast Air Basin, and more than 800

lives a year in the San Joaquin Valley.

EWG urges the Air Resources Board to resist pressure from polluters and

adopt the PM standards recommended by state scientists. Exemptions for

agriculture should be eliminated. To further protect children and other sensitive

populations, ARB should also set eight-hour PM standards, as it has for ozone.

Finally, the state PM standards must be more rigorously enforced.

Tougher state

standards for

particulate air

pollution could

save more than

6,500 lives and

half a billion

dollars a year.
ENVIRONMENTAL WORKING GROUP 6
ENVIRONMENTAL WORKING GROUP 7

A Life and Death

Decision

Particulate air pollution causes or contributes to the deaths of more Californians

than car accidents, murder and AIDS combined, according to an analysis of

state data by Environmental Working Group. EWG’s investigation found that

state health officials are proposing new air pollution rules that could save or

extend more than 6,500 lives a year, but the safer standards face entrenched

opposition from a deep-pockets alliance of major oil companies and

automakers.

Airborne microscopic particles, much smaller than the width of a human hair,

are known as particulate matter, or PM. (The smallest particles are often called

“fine” particulates; the larger ones, still very tiny, are called “coarse” particulates.)

California Department of Health Services (DHS) data shows that respiratory

illnesses caused or made worse by PM pollution are responsible for the deaths

of more than 9,300 Californians a year. That is three times more than are killed

in car accidents, 4.6 times more than those who are victims of homicide and

six times the number who die of AIDS. (Table 1.) What’s more, even this

number is an underestimate of the total number of PM-related deaths each

year since it includes all deaths due to long-term exposure but only includes

some of those due to short-term exposure to particulate air pollution1

.

The air polluters’ lobby tries to divert attention from the overwhelming evidence

that particulate matter is deadly by arguing that compliance with the “impossibly

stringent” proposed new standards would be too costly and would not produce

Source: EWG, from California Department of Health Services 1999.

Table 1.

Particulate air

pollution in

California causes

or contributes to

more than 9,000

deaths each year.

 Cause of Death Number of Deaths 

in 1999

Particulate air pollution 9,340

Motor vehicle accidents 3,140

Suicide 3,047

Accidental poisonings 2,221

Homicide 2,042

HIV/AIDS 1,558

Accidental falls 1,202

Drownings 397
ENVIRONMENTAL WORKING GROUP 8

“any greater protection of public health than the current California standards.”

(Ford 2002, AAM 2002.) But EWG’s five-month review of hundreds of state,

national and international studies found just the opposite: By saving lives and

preventing illnesses, tougher PM standards could save the state and its citizens

more than half a billion dollars a year.

The price tag: $1 billion a year

Each year, PM pollution is responsible for more than 16,000 hospital or

emergency room admissions, at an estimated health care cost of $132 million.

PM-triggered illnesses also cause Californians to miss almost five million work

days a year, a loss to the state’s economy of more than $880 million2

. More

difficult to put a price tag on are the thousands of less severe illnesses that

result every year from PM pollution, including 600,000 asthma attacks and

13,500 cases of chronic bronchitis in California. (Tables 2, 3.)

Particulates, which are taken deep into the lungs by inhalation, have been

linked with a long list of respiratory ailments such as chronic cough, chest

pain, breathlessness, wheezing, phlegm, chronic bronchitis, decreased lung

growth, decreased lung function, and the exacerbation of asthma symptoms.

Table 2. Proposed new standards would prevent hundreds of

thousands of illnesses each year.

Source: EWG, from ARB/OEHHA 2001, EWG 2002.

Notes: In this table, the long-term mortality values are for PM2.5 and the short-term mortality

values are for PM10. Long-term mortality is deaths from long-term exposure to particulates, while

short-term is deaths from short-term exposure. Because the estimates of long-term mortality include some but not all short-term deaths, the two cannot be added together to get an estimate of

total mortality.

Ages 

Considered

Cases at 

Current PM 

Levels

Cases 

Under 

Proposed 

Standards

Cases 

Avoided 

Cases 

Reduced by

Long-term Mortality 30+ 9390 2865 6525 69%

Short-term Mortality All 4063 1772 2291 56%

Chronic Bronchitis 27+ 13530 5696 7835 58%

Chronic Obstructive Pulmonary 

Disease Hospital Admissions 65+ 2115 923 1192 56%

Pneumonia Hospital Admissions 65+ 3061 1340 1721 56%

Cardiovascular Disease Hospital 

Admissions 65+ 5452 2395 3057 56%

Asthma Hospital Admissions 64- 1624 692 933 57%

Asthma Emergency Room Visits 64- 3992 1691 2301 58%

Asthma Attacks All 592736 254466 338270 57%
ENVIRONMENTAL WORKING GROUP 9

PM concentrations have also been shown to be associated with hospital admissions for a wide variety of cardiovascular and pulmonary diseases, including asthma. Groups particularly at risk include children, the elderly, people

who already suffer from respiratory illness, and those of low socioeconomic

status, who tend to live in areas where particulate pollution is most severe.

In recent years, a major international scientific effort has produced a flood of

studies that has clearly established that PM pollution can kill people.

Epidemiological studies have been conducted in over 200 cities worldwide,

examining the effects of different exposure durations, and accounting for

contributing factors including age, smoking habits, weather, and other

pollutants. The results have been remarkably consistent: Both short- and longterm exposure to particulate pollution at levels lower than currently experienced

by millions of California residents can cause death. Compared to just a few

years ago, scientists today are much more likely to say plainly that PM kills,

than that it contributes to death.

California’s current PM standards were set in 1982. New standards proposed

by scientists at the state Air Resources Board (ARB) and Office of Environmental

Health Hazard Assessment (OEHHA) would reduce the number of PM-triggered

deaths and illnesses dramatically. The scientists say cutting allowable levels of

PM to recommended levels will reduce deaths by at least 69 percent, asthma

attacks by 57 percent, hospital visits by 56 percent and cases of chronic

bronchitis by 58 percent. (Table 2.) Statewide, the recommended standards

would result in an annual reduction of about 3 percent of all mortality in the

population above age 30. (ARB/OEHHA 2001.) EWG estimates that these new

PM-standards would also result in savings of state direct and indirect costs of

more than $580 million a year. (Table 3.)

The Children’s Environmental Health Act

Gov. Gray Davis’ appointed ARB directors are scheduled to vote on the

proposed new standards in June 2002. Their decision is being watched closely

by health and environmental officials and researchers across the country. In

1999, California enacted the landmark Children’s Environmental Health Act

(SB 25), the first law anywhere in the U.S. to require that air pollution standards

must be stringent enough to protect children – as opposed to almost all other

environmental regulations designed to protect the average adult male. SB 25

required the ARB to review all of the state’s air pollution standards to determine

whether they adequately protect children. A preliminary review determined

that the current PM standards were inadequate and that revising them should

be ARB’s highest priority. Other standards determined to be inadequate must

be revised at a rate of one a year3

. The proposed PM standards could again

make California the national leader in air quality standards to protect public

health – but not if the air polluters’ lobby gets its way.

The Western States Petroleum Association, the Alliance of Auto Manufacturers,

the Engine Manufacturers Association and other industry groups and individual

companies have mounted a well-financed major campaign against the proposed

Hundreds

of studies

worldwide

confirm that

exposure to

particulate

pollution at levels

lower than

millions of

 Californians

breathe can

cause death.
ENVIRONMENTAL WORKING GROUP 10

standards. Their tactics are familiar: carping on minor inconsistencies between

scientific studies, exaggerating uncertainties although PM is perhaps the moststudied type of air pollutant, and drawing on industry-funded studies to dispute

the overwhelming consensus of peer-reviewed academic and government

research. If their campaign, for which a small army of lobbyists in Sacramento

has millions of dollars to spend, is only partly successful in watering down the

proposed standards, thousands more Californians will die from dirty air each

year.

Unlike most other air pollutants, particulates are regulated by size. Particles

with diameters less than or equal to 10 microns are called PM10 and are often

referred to as “coarse particles.” Particulates with diameters less than or equal

Table 3. Costs Associated With PM10-related Illness in California.

Source: ARB/OEHHA 2001, EWG 2002, Abt 2000, U.S. Census 2000.

Notes:

1) Hospital charge cost only. Mean hospital stay is 6.02 days with a

mean charge of $11,722 (1999 dollars). (Abt 2000)

2) Hospital charge cost only. Mean hospital stay is 7.01 days with a

mean charge of $13,929 (1999 dollars). (Abt 2000)

3) Hospital charge cost only. Mean hospital stay is 5.44 days with a

mean charge of $17,794 (1999 dollars). (Abt 2000)

4) Hospital charge cost only. Mean hospital stay is 3.03 days with a

mean charge of $6,303 (1999 dollars). (Abt 2000)

5) The average asthma ER visit cost is $299 (1999 dollars). (Abt 2000)

6) The median per-day income of California residents in the year 2000

was $180. (US Census 2002)

Ages 

Considered

Number at 

Current PM10 

Level

Cost at Current PM10 

Level (1999 $)

Number Avoided 

Under Proposed 

New Standards

Savings Under 

Proposed New 

Standards

Chronic Obstructive 

Pulmonary Disease 

Hospital Admissions 1

65+ 2,115 $24,792,990 1,192 $13,972,624

Pneumonia Hospital 

Admissions 2 65+ 3,061 $42,639,263 1,721 $23,971,809

Cardiovascular Disease 

Hospital Admissions 3 65+ 5,452 $34,362,621 3,057 $19,268,271

Asthma Hospital 

Admissions 4 64- 1,624 $28,904,937 933 $16,601,802

Asthma Emergency Room 

Visits 5 64- 3,992 $1,193,527 2,301 $687,999

Work Loss Days 6 64- 4,910,652 $883,917,360 2,814,815 $506,666,700

Total 4,926,896 $1,015,810,698 2,824,019 $581,169,205 
ENVIRONMENTAL WORKING GROUP 11

to 2.5 microns are called PM2.5 and are often referred to as “fine particles.” (A

single human hair has a diameter of 50 to 100 microns.) California’s current

standards regulate only PM10, but the proposed new standards would also

cover PM2.5.

PM contains heavy metals, nitrates, sulfates, aerosols and other toxic chemicals,

as well as ordinary soot, soil, dust and smoke from both man-made and natural

sources, including cars, industrial pollution and unpaved roads. Recent research

suggests that PM from industrial and other man-made sources is more harmful

to human health than dust from natural sources. (See Chapter 3.) The makeup

of PM pollution varies considerably among different locations and at different

times of the year (or even day) in the same location. As a result, two areas in

California with the same level of particulates in the air may have distinctly

different PM problems, and within counties where overall PM levels are

relatively low, individual cities or neighborhoods may be exposed to high

levels. Although annual average PM levels have declined in recent years, only

small, mostly rural Lake County is in full compliance with current state standards.

Statewide, total PM emissions are on the rise, and the great majority of

Californians are exposed to potentially harmful levels:

♦ Over 99 percent of Californians breathe air that violates the

current PM10 standards during at least part of the year. (ARB/

OEHHA 2000.)

♦ Fifty-five of fifty-eight counties have average annual PM10

concentrations that exceed the proposed standards and fourteen

counties (or portions of counties) have average annual

concentrations that are at least twice as high, based on the last

three years of ARB monitoring data4. (Table 4.)

♦ Forty-three counties (or portions of counties) have average

annual PM2.5 concentrations that exceed the proposed

standards, based on the last two years of ARB monitoring data5.

(Table 4.)

Preventing deaths and asthma

The worst particulate pollution in the state is found in Imperial County (and

an adjoining part of Riverside County). But far more Californians are affected

by the severe problems in the South Coast Air Basin (Los Angeles, Orange,

Riverside and San Bernardino counties) which consistently records the highest

PM levels of any U.S. metro area, and the eight-county San Joaquin Valley,

which ranks among the six worst air basins in the country for particulate

pollution. (Grossi 2002, Table 4.) Considering the same factors state scientists

used in calculating statewide PM-related deaths and illnesses, EWG estimates

that the proposed new standards could prevent or delay more than 4,200

deaths a year in the South Coast Air Basin, and more than 800 deaths a year in

The Los Angeles–

Riverside

metro area has

the worst

particulate air

pollution in the

U.S., and the San

Joaquin Valley's

problem is also

among the worst.
ENVIRONMENTAL WORKING GROUP 12

Table 4.

55 of California's

58 counties are not

in full compliance

with existing PM

standards.

Source: EWG, from ARB/

OEHHA 2001.

County Portion of 

County*

PM10 Annual 

Average 

(ug/m3)**

PM2.5 Annual 

Average 

(ug/m3)***

Alameda 21.7 15.8

Alpine 16.7 8.5

Amador 23.0 16.6

Butte 24.5 12.3

Calveras 23.0 16.6

Colusa 24.5 12.3

Contra Costa 21.7 15.8

Del Norte 17.5 7.5

El Dorado Lake Tahoe 

Basin 20.8 7.5

El Dorado Mountain 

Counties Basin 23.0 16.6

Fresno 39.5 22.3

Glenn 24.5 12.3

Humbolt 17.5 7.5

Imperial 70.2 13.1

Inyo 16.7 8.5

Kern Mojave Basin 21.6 10

Kern San Joaquin 

Basin 39.5 22.3

Kings 39.5 22.3

Lake 10.8 ≤ 5

Lassen 13.0 ≤ 5

Los Angeles Mojave Basin 21.6 10

Los Angeles South Coast 

Basin 40.7 22.2

Madera 39.5 22.3

Marin 21.7 15.8

Mariposa 23.0 16.6

Mendocino 17.5 7.5

Merced 39.5 22.3

Modoc 13.0 ≤ 5

Mono 16.7 8.5

Monterey 24.2 7.5

Napa 21.7 15.8

Nevada 23.0 16.6

Orange 40.7 22.2

Placer Lake Tahoe 

Basin 20.8 7.5

Placer Sac Valley 

Basin 24.5 12.3

Plumas 23.0 16.6

Riverside Mojave Basin 21.6 10

Riverside Salton Sea 

Basin 70.2 13.1

Riverside South Coast 

Basin 40.7 22.2

Sacramento 24.5 12.3

San Benito 24.2 7.5

San Bernardino Mojave Basin 21.6 10

San Bernardino South Coast 

Basin 40.7 22.2

San Diego 28.8 15.6

21.7 15.8

San Joaquin 39.5 22.3

23.0 11.8

San Mateo 21.7 15.8

23.0 11.8

Santa Clara 21.7 15.8

Santa Cruz 24.2 7.5

Shasta 24.5 12.3

Sierra 23.0 16.6

Siskiyou 13.0 ≤ 5

Solano Sac Valley 

Basin 24.5 12.3

Solano San Francisco 

Basin 21.7 15.8

Sonoma North Coast 

Basin 17.5 7.5

Sonoma San Francisco 

Basin 21.7 15.8

Stanislaus 39.5 22.3

Sutter 24.5 12.3

Tehama 24.5 12.3

Trinity 17.5 7.5

Tulare 39.5 22.3

Tuolumne 23.0 16.6

Ventura 23.0 11.8

Yolo 24.5 12.3

Yuba 24.5 12.3

San Luis Obispo

Santa Barbara

San Francisco
ENVIRONMENTAL WORKING GROUP 13

the San Joaquin Valley. Each year, more than 76,000 asthma attacks could be

averted in Riverside and San Bernardino counties alone. (Table 5.)

In December 2001, ARB and OEHHA staff scientists proposed that California’s

annual PM10 standard be lowered by one-third, from 30 micrograms per cubic

meter of air (μg/m3) to 20 micrograms, and that an annual state PM2.5 standard

be set at 12 μg/m3

. But the agencies also had to decide about standards for

short-term (24-hour) exposures to PM. They proposed to leave the short-term

standard for PM10 unchanged at 50 μg/m3. They at first opted not to propose

a state short-term standard for PM2.5, continuing to rely on the federal level of

65 μg/m3

. After criticism from an external scientific review panel and pressure

from state environmental advocates, however, ARB and OEHHA decided a

state short-term PM2.5 standard was necessary, and in March 2002 proposed a

level of 25 μg/m3

. (Figures 1 and 2.)

When the ARB directors meet to set the final standards, the stakes are high. If

the annual PM10 standard is strengthened only slightly to 28 μg/m3

, and the

PM2.5 standard is set at the federal level of 15 μg/m3

, as the oil companies

and automakers advocate, the result would be 3,000 more premature deaths,

3,000 more hospital admissions, 1,000 more emergency room visits for asthma,

3,500 more cases of chronic bronchitis, and 150,000 more asthma attacks each

year than if the standards were set at the proposed levels. For thousands of

Californians, it will be literally a life-and-death decision.

Recommendations

♦ Directors of the Air Resources Board should resist pressure

from polluters and adopt both the annual and short-term PM10

and PM2.5 standards recommended by state scientists.

♦ The de facto state exemption from PM regulations for most

agricultural activities – a major source of particulate pollution

in California – should be eliminated.

♦ To further protect children and other sensitive populations from

acute levels of particulates, ARB should also set shorter-term

standards for PM10 and PM2.5, on the model of the state’s

eight-hour standard for ozone air pollution.

♦ The PM standards adopted by the state should be rigorously

enforced. Currently the standards are non-binding, making

enforcement inconsistent and ineffective.

Gov. Davis' air

quality board

should adopt

the tougher

regulations

recommended by

state scientists,

and enforce

them rigorously.
ENVIRONMENTAL WORKING GROUP 14

Footnotes

1

 This figure is for estimated mortality due to long-term exposures to PM2.5 air pollution.

It is difficult to arrive at an absolute number of PM-related deaths because of overlap

in various estimates. For instance, the figures for long-term mortality are believed to

encompass some but not all short-term deaths, and therefore estimates of short and

long-term mortality can not be simply added together to get an estimate of total mortality.

2

 The median per-day income of California residents in the year 2000 was $180 (=46,802

dollars per year / 260 work days per year). (U.S. Census Bureau 2000.) The actual

number of work days lost to PM10-related illness is 4,910,652. (OEHHA/ARB 2001.)

The estimated cost to the state’s economy is the product of these two numbers.

3

 OEHHA categorized the air pollutants under review into two tiers based on the

agency’s assessments of potential risks to public health. The first tier includes PM,

ozone and nitrogen dioxide. The second tier includes lead, carbon monoxide, and

hydrogen sulfide.’ (OEHHA/ARB 2001.)

4

 Average PM10 levels were calculated by ARB using the last three years of data available

(1998-2000). (OEHHA/ARB 2001.)

5

 Average PM2.5 levels were calculated by ARB using the last two years of data (1999-

2000), which is all the monitoring data available. (OEHHA/ARB 2001.)
ENVIRONMENTAL WORKING GROUP 15
ENVIRONMENTAL WORKING GROUP 16
ENVIRONMENTAL WORKING GROUP 17

California’s Particulate

Problem

Emissions of particulates have been increasing in California for decades, from

2,017 tons of PM10 per day in 1980, to 2,240 tons per day in 1990, to 2,312

tons per day in 2000. (ARB 2001.) However, the increase has been far from

uniform across the state. During this period, PM10 emissions in some counties

have remained relatively steady or declined, while other counties have seen a

marked increase. For instance, between 1975 and 2000, emissions in San

Bernardino County increased by 93 percent and in San Diego County by 70

percent. (ARB 2001.) The increase in emissions comes from many sources,

but one clear cause is the ever-growing dependence on automobiles: From

1975 to 2000 the number of vehicle miles traveled in California more than

doubled, from 351 million miles per day to 800 million. (ARB 2001.)

While the total amount of emissions continues to rise, concentrations of PM10

measured by air quality monitors have actually declined. Statewide, annual

mean concentrations measured by the state’s 250 air monitors dropped 20

0

10

20

30

40

50

60

70

Figure 1. Proposed and Existing PM2.5 Standards

Proposed

California

Annual

Standard

Current

Federal

Annual

Standard

Proposed

California

24-hour

Standard

Current

Federal

24-hour

Standard
ENVIRONMENTAL WORKING GROUP 18

percent between 1988 and 1999, from about 80 μg/m3 to 60. A big reason for

this apparent discrepancy is that most of the monitors are in the South Coast

Air Basin, where in recent years progress has been made in reducing PM

emissions. Since the current PM standards were adopted in 1982, improvements

in air quality have been achieved statewide, but today all counties except

Lake County still fail to meet the state’s short-term PM10 standard. (Lassen, Modoc

and Siskyou counties lack enough data to measure compliance.) Twenty counties fail to

meet even the considerably weaker federal short-term PM10 standard.’ (Table 4.)

Problem areas

In most areas of the state with elevated PM levels, the problem is not limited to shortterm spikes in concentration but is a year-round concern. By far the highest levels are

found in Imperial County and an adjacent portion of Riverside County, with an annual

average of 70 μg/m3

 of PM10 – almost 3.5 times the proposed state standard. But

annual levels of 40 μg/m3

 or more of PM10 – twice the proposed standard–– are

recorded in twelve other counties or portions of counties: Fresno, Kern, Kings, Los

Angeles, Madera, Merced, Orange, Riverside, San Bernardino, Stanislaus, San Joaquin

and Tulare. (Table 4.)

PM differs from many other types of air pollution in that it is not a single

compound, but rather a highly complex mixture of small solid particles and

Figure 2. Proposed and Existing PM10 Standards.

0

20

40

60

80

100

120

140

160

Proposed

California

Annual

Standard

Current

California

Annual

Standard

Current

Federal

Annual

Standard

Current

California

24-hour

Standard

Current

Federal

24-hour

Standard
ENVIRONMENTAL WORKING GROUP 19 Table 5. Consequences of PM exposure, by county. County Source: EWG, from ARB/OEHHA 2001. Deaths Due to PM2.5 at Current Levels Fewer Deaths if Proposed Standards Achieved Deaths Due to PM10 at Current Levels Fewer Deaths if Proposed Standards Achieved Admissions due to PM10 at Current Levels Fewer Admissions if Proposed Standards Achieved Visits Due to PM10 at Current Levels Fewer Visits if Proposed Standards Achieved Attacks Due to PM10 at Current Levels Fewer Attacks if Proposed Standards Achieved Days lost due to PM10 at current levels Fewer Days Lost if Proposed Standards Achieved Alameda 317 178 92 13 36 5 89 13 12,944 1,861 142,140 15,940 Alpine 0 0 0 0 0 0 0 0 6 0 93 0 Amador 12 7 4 1 1 0 2 1 349 80 3,334 626 Butte 32 3 24 8 6 2 14 5 2,257 704 21,072 5,629 Calveras 14 9 5 1 1 0 3 1 404 93 3,845 723 Colusa 2 0 1 0 1 0 1 0 209 65 2,053 548 Contra Costa 197 111 63 9 23 3 58 8 8,507 1,223 92,286 10,349 Del Norte 0 0 2 0 0 0 1 0 160 0 2,156 0 El Dorado 85 52 13 2 4 1 10 2 1,503 304 15,576 2,534 Fresno 311 243 126 83 49 33 121 81 17,894 11,905 138,277 99,442 Glenn 4 0 2 1 1 0 2 1 294 92 2,835 757 Humbolt 0 0 7 0 2 0 5 0 735 0 9,922 0 Imperial 15 4 38 32 17 15 41 35 6,370 5,348 40,840 42,511 Inyo 0 0 1 0 0 0 1 0 93 0 1,242 0 Kern 223 172 98 61 37 23 90 57 13,296 8,317 106,695 69,919 Kings 40 31 16 11 8 5 20 14 2,898 1,928 23,021 16,556 Lake 0 0 0 0 0 0 0 0 38 0 2,639 0 Lassen 0 0 0 0 0 0 1 0 78 0 2,061 0 Los Angeles 3555 2,759 1,387 930 599 405 1,469 997 217,366 146,105 1,672,103 1,220,537 Madera 50 39 21 14 7 5 18 12 2,756 1,833 21,026 15,121 Marin 55 31 16 2 6 1 15 2 2,217 319 23,452 2,630 Mariposa 6 4 2 0 0 0 1 0 170 39 1,644 309 Mendocino 0 0 5 0 1 0 3 0 501 0 6,680 0 Merced 79 62 32 21 13 9 32 22 4,713 3,136 36,585 26,310 Modoc 0 0 0 0 0 0 0 22 0 521 0 Mono 0 0 0 0 0 0 0 0 67 0 1,016 0 Monterey 0 0 27 8 12 4 30 9 4,391 1,318 44,102 11,262 Napa 37 21 11 2 3 0 7 1 1,114 160 11,536 1,294 Nevada 30 18 9 2 2 1 6 1 916 211 8,804 1,655 Orange 956 744 410 277 182 124 447 306 66,218 44,928 506,007 374,751 Placer 25 2 21 6 7 2 19 6 2,733 832 26,429 6,869 Plumas 7 4 2 0 1 0 1 0 207 48 1,981 372 Riverside 583 431 353 256 112 82 272 200 42,149 30,675 296,622 243,660 Sacramento 132 12 106 33 37 12 92 29 13,594 4,238 133,938 35,779 San Benito 0 0 3 1 2 0 4 1 582 175 5,969 1,524 San Bernardino 486 370 231 144 95 60 234 147 34,127 21,263 276,676 180,041 San Diego 560 308 279 131 110 52 273 130 40,465 19,074 358,663 159,824 San Francisco 203 114 60 9 19 3 46 7 6,964 1,001 73,543 8,247 San Joaquin 251 196 101 67 34 23 84 57 12,616 8,393 96,729 69,562 San Luis Obispo 26 0 21 5 7 2 16 4 2,471 581 24,534 4,727 San Mateo 150 84 45 6 17 2 42 6 6,340 912 67,890 7,613 Santa Barbara 37 0 29 7 11 3 27 6 4,000 940 40,532 7,809 Santa Clara 271 152 82 12 42 6 104 15 15,085 2,169 166,914 18,718 Santa Cruz 0 0 20 6 8 2 19 6 2,793 838 28,076 7,170 Shasta 25 2 19 6 5 1 12 4 1,814 566 17,043 4,553 Sierra 1 1 1 0 0 0 0 0 35 8 339 64 Siskiyou 0 0 0 0 0 1 0 102 0 2,428 0 Solano 60 29 23 5 11 2 26 5 3,790 773 40,655 6,672 Sonoma 99 56 35 4 11 1 26 4 3,938 520 42,970 4,336 Stanislaus 193 150 79 52 27 18 67 45 10,006 6,657 76,857 55,272 Sutter 9 1 7 2 2 1 6 2 877 273 8,519 2,276 Tehama 9 1 7 2 2 1 4 1 623 194 5,802 1,550 Trinity 0 0 0 0 0 0 0 0 76 0 966 0 Tulare 145 113 58 38 23 15 56 37 8,238 5,481 63,764 45,855 Tuolumne 18 11 5 1 1 0 3 1 542 125 5,148 968 Ventura 57 0 47 11 21 5 52 12 7,544 1,773 78,649 15,153 Yolo 15 1 13 4 5 2 13 4 1,874 584 18,826 5,029 Yuba 8 1 6 2 2 1 5 1 669 209 6626 1,770 Total 9,390 6,525 4,063 2,291 1,624 933 3,992 2,301 592,736 338,270 4,910,652 2,814,815 Long-term mortality Work Loss Days Asthma Attacks Short-term mortality Asthma Emergency Room Visits Asthma Hospital Admissions
ENVIRONMENTAL WORKING GROUP 20

liquid droplets suspended in air. These particles may be emitted directly into

the air or they may form in the atmosphere from “precursor” chemicals such

as sulfur and nitrogen compounds. Substances that comprise PM range from

soot, soil, organics, dust, and smoke to heavy metals, aerosols, nitrates, and

sulfates. The makeup of PM pollution varies considerably among different

locations and at different times of the year (or even day) in the same location.

The diverse composition and distribution of particulate pollution makes it

especially difficult to assess and control.

Particulate pollution comes from both natural and human sources. The five leading

sources of PM10 emissions in California are in the catchall category of “dust” – unpaved

road dust, paved road dust, and windblown dust together comprise about 55 percent

of the total, with construction and agriculture each contributing another 9 percent.

(Table 6.) Other significant human sources of PM10 emissions are industrial pollution

and fuel combustion (6 percent combined), fireplaces and wood stoves (6 percent),

burning waste (6 percent) and vehicle exhaust (5 percent). (ARB 2000a.)

Unlike most air pollutants, which are regulated based on their chemical

composition, particles are regulated based on their size: those with diameters

greater than 10 microns, those with diameters less than or equal to 10 microns

(PM10), and those with diameters equal to or less than 2.5 microns (PM2.5).

(One micron is one millionth of a meter, and a single human hair has a

diameter of 50 to 100 microns.) The human respiratory system can filter out

most particles larger than 10 microns. But as the particles get smaller they are

Table 6.

Sources of PM10

pollution in

California.

* includes cars, trucks, airplanes, trains, and boats

Source: EWG, from ARB 2000.

PM10 Source

Tons of PM10 

Emitted per 

Year

Percent of 

Total

Unpaved road dust 235,060 27%

Paved road dust 140,890 16%

Windblown dust 106,945 12%

Construction 74,825 9%

Farming 79,935 9%

Woodstoves & fireplaces 51,465 6%

Waste burning 50,735 6%

Mobile vehicles* 45,625 5%

Wildfires 31,755 4%

Industrial 32,485 4%

Fuel combustion 15,695 2%

Other 11,315 1%

Total 876,730 100%
ENVIRONMENTAL WORKING GROUP 21

Table 7. Comparison of PM2.5 (Fine Particles) and PM10 (Coarse Particles).

Source: EWG, from US EPA 1996.

FINE COARSE

Formed from Gases Large solids/droplets

Formed by Chemical reaction Mechanical disruption 

(crushing, grinding, etc.)

Nucleation Evaporation of sprays

Condensation Suspension of dusts

Coagulation

Evaporation 

Composed of Sulfate Resuspended dusts

Nitrate Soil, dust, street dust

Ammonium Oxides of crustal elements

Hydrogen ion Sea salt, calcium carbonate

Elemental carbon Pollen, mold, fungal spores

Organic compounds Plant/animal fragments

Metals Tire wear debris

Particle-bound water

Solubility Largely soluble Largely insoluble

Sources Combusiton of coal, oil, 

gasoline, diesel, wood

Resuspension of industrial 

dust and soil tracked onto 

roads and streets

Atmospheric 

transformation products 

of nitrogen oxides, 

sulfur dioxide, and 

organics

Suspension from disturbed 

soil, e.g. farming, mining

High temperature 

processes, smelters, 

steel mills, etc.

Biological sources

Construction

Coal and oil combustion

Ocean spray

Lifetime Days to weeks Minutes to hours

Travel distance 100s to 1000s of 

kilometers <1 to 10s of kilometers
ENVIRONMENTAL WORKING GROUP 22

able to penetrate deeper into the lungs, and are harder for the body to remove.

Therefore, over the past two decades, researchers and regulators have focused

on ever-smaller inhalable particles. The U.S. Environmental Protection Agency

first set standards for PM10 in 1987 and set standards for PM2.5 in 1997.

PM10 and PM2.5 also differ in their sources, how they are formed, composition,

and lifetime in the atmosphere. Fine particulates are generated from fossil fuel

combustion and other high-temperature processes, are formed from gases

which then react and coagulate in the atmosphere and persist in the air for

days or weeks. Coarse particulates are usually generated from the suspension

of dust from natural or man-made sources, are composed of very small particles

or droplets rather than gases, and remain in the air for minutes to hours.

(Table 7.) (U.S. EPA 1996.)

Dust in the wind

More than 70 percent of PM10 emissions in the state are from “dust,” which includes

wind-blown dust from paved and unpaved roads, farming and ranching, and construction

sites. Agriculture is a major source of PM10, but its impact is somewhat hidden because

ag-related emissions fall into a number of different categories: farming operations,

windblown dust, waste burning, industrial processes and farm vehicles. All told,

California agriculture produces 459 tons of PM10 a day, or more than 167,500 tons a

year. The farm-related particulates problem is so severe in the San Joaquin Valley that

the region has repeatedly been unable to meet federal PM standards, and stands to lose

more than $2 billion in federal highway funds if the eight counties can’t achieve a five

percent annual reduction in particulate levels – the only air basin in the country to be

hit with such sanctions.

Yet the agricultural industry is exempt from most air pollution laws. The federal

Clean Air Act exempts emissions from farm equipment of less than 175

Table 8. Leading Industrial Sources of PM10 Pollution in California.

Source: EWG, from ARB 2001.

 Facility Name City

Tons of PM10 

Emitted per 

Year

ADM Inc (Wood Products) Benicia 1,376

US Borax Boron 614

Kern Oil & Refining Bakersfield 544

IMC Chemicals Trona 526

Mitsubishi Cement Lucerne Valley 472

Chevron El Segundo 472

Arco Carson 452

Ampine (Wood Products) Martell 447

Port of Stockton Stockton 436

 Martinez Refining Company Martinez 433 
ENVIRONMENTAL WORKING GROUP 23

horsepower. Strictly speaking, California doesn’t exempt farm sources from

air pollution regulations, but does exempt farm operations from having to

obtain an air pollution permit – and without the conditions attached to a

permit, there is no effective control on emissions. The EPA has announced

that it will commission the National Academy of Sciences to study agricultural

sources of air pollution, which could lead to full-scale regulation of air pollution

from farming operations.

Dirty diesels

“Mobile” sources (vehicles) contribute about 5 percent of California’s annual

PM10 emissions. Passenger cars and light trucks are responsible for about a

quarter of this pollution, with most of the rest coming from heavy duty

trucks, farm and construction and both commercial and recreational boats.

But the bad actor of the category is diesel fuel. Even though diesel-fueled

vehicles make up only 4 percent of the 31 million vehicles on the road in

California, diesels are responsible for 53 percent of all auto-related PM

emissions in California. (ARB 2000b.) And in addition to the adverse health

effects associated with all other sources of particulate matter, diesel PM contains

many known carcinogens. ARB estimates that diesel-derived PM is responsible

for 900 excess cases of cancer per 1 million people exposed over a 70-year

lifetime, accounting for 70 percent of the known statewide cancer risk from

outdoor air toxics. (ARB 2000b.)

Industrial emissions account for about 4 percent of California’s PM10 pollution.

The list of the leading industrial polluters includes petrochemical companies

like Chevron, Arco and other refiners, but by far the worst offender is ADM

Inc., a manufacturer of wood products in Benicia, Solano County, with more

than 1,300 tons emitted in 2000. (Table 8.) Collectively, the ten worst industrial

PM polluters in the state emitted 5,300 tons of PM10 in 2000.

Agriculture is the

largest industry

in California

and a major

source of

particulates, but

is exempt from

most air

pollution rules.
ENVIRONMENTAL WORKING GROUP 24
ENVIRONMENTAL WORKING GROUP 25

Air Pollution, Illness,

and Death

Scientists began investigating the link between air pollution, illness and death

in response to a number of severe air pollution episodes that sickened and

killed thousands of residents in the United States, England and Belgium between

1930 and 1952. Most of the early research looked the effects of very high

pollution levels, but more recent inquiry has focused on how low-to-moderate

levels of particulates and other air pollutants affect human health. In the past

decade the amount of research in this area has exploded, as literally hundreds

of studies have been conducted just on the relationship between particulates

and death. The scientific consensus is undebatable: Particulates are significantly

more harmful than previously realized, and levels well below current state

and federal air quality standards can cause or contribute to death.

PM pollution has been linked to an array of respiratory ailments in children

and adults, including chronic cough, chest pain, breathlessness, wheezing,

phlegm, and chronic bronchitis. (Abbey et al. 1995a,b, Pope and Dockery

1991, Braun-Fahulander et al. 1992, Hruba et al. 2001, Zemp et al. 1999.) PM

also affects overall lung functioning. Researchers have found that levels of PM

commonly experienced by Californians are associated with small but significant

decreases in the ability of both children and adults to take and hold deep

breaths. (Hoek et al., 1998, Raizenne et al. 1996, Ackerman-Liebrich et al.

1997.)

Kids + PM = Damaged lungs

More troubling, PM can also retard the growth of children’s lungs. The Children’s

Health Study, a long-term investigation of the health effects of air pollution

conducted on more than 3,500 children from 12 communities in Southern

California, found that PM10 and PM2.5 exposure was associated with decreases

in both lung function and lung growth. (Peters et al. 1999, Gauderman et al.

2000.) A follow-up study found that children who moved to areas with lower

PM levels showed increased lung growth and functioning, while lung growth

and function continued to decline in those who moved to areas with even

higher PM levels. (Avol et al. 2001.)

Wherever the link has been investigated, including many studies conducted

in California, the results have been consistent: For every 10 micrograms of

PM10 added to every cubic meter of air, symptoms of respiratory illness increase,

with some studies showing increases of up to 40 percent. State scientists

estimate that more than 13,500 current cases of chronic bronchitis in Californians

Relatively

small increases

in airbone

particulates can

significantly

increase the

incidence of

respiratory

disease and

death.
ENVIRONMENTAL WORKING GROUP 26

over the age of 27 are due to particulate air pollution. PM is also responsible

for upper respiratory symptoms in an estimated 418,000 California children

between the ages of 9 and 11, for lower respiratory symptoms in almost

400,000 children between the ages of 7 and 14, and almost five million lost

days of work each year for PM-related illnesses1. (ARB/OEHHA 2001.)

Between 1980 and 1994 the prevalence of asthma in the United States increased

by more than 75 percent. (Mannino et al., 1998.) Asthma now affects more

than 10 million adults and almost five million children. While the current

scientific consensus holds that PM pollution does not cause asthma, studies in

California and elsewhere have repeatedly found that PM can significantly

exacerbate the disease.

Both PM2.5 and PM10 are associated with many different measures of the

severity of asthma, including frequency of attacks, increased use of medication,

emergency room visits and hospitalization. (Ostro 2001, Delfino 1998, Pope

and Dockery 1992, Yu et al. 2000, Gielen et al. 1997.) A study of asthmatic

African-American children in Los Angeles found that one-hour maximum levels,

24-hour averages, and multi-day averages of PM10 were all associated with

increases in asthmatic symptoms. (Ostro et al 2001.) State scientists estimate

that almost 600,000 asthma attacks, almost 4,000 emergency room visits and

more than 1,600 hospital admissions each year are linked to PM-induced asthma.

PM is also associated with increased hospital visits for illnesses other than

asthma. Research in dozens of cities in California and other states has

consistently found that short-term PM10 and PM2.5 exposures are associated

with hospital admissions for cardiovascular and pulmonary diseases such as

heart attack, congestive heart failure, cardiac arrhythmia and chronic obstructive

pulmonary disease. (Linn et al 2000, Moolgavkar 2000 a,b, Samet et al 2000a,

Sheppard et al 1999, among others). Overall, these studies have found that for

each 10-microgram increase in PM10 levels in a cubic meter of air, hospital

admissions for cardiovascular and respiratory diseases rose by 1.25 to 5 percent.

(ARB/OEHHA 2001.) This holds true in locations where PM10 pollution was

at low to moderate levels, as well as where levels were high. Data for PM2.5

is more sparse, but suggests that incremental increases in fine particulates

may be associated with even greater increases in hospital admissions.

State scientists estimate each year PM10 pollution is responsible for 2,100

hospital admissions for chronic obstructive pulmonary disease, 3,000 admissions

for pneumonia and 5,500 admissions for cardiovascular diseases. These

estimates account only for people age 65 and older, but research has found

increases in hospital admissions for these illnesses among younger people as

well. (Table 9.)

Common sense says that breathing polluted air daily over an extended period

of time is more dangerous than exposure for a few hours or days. Observed

increases in mortality from short-term PM exposures are three to four times

lower than those from long-term exposures. (ARB/OEHHA 2001.) Yet the

impact of short-term PM exposures on public health cannot be ignored. ARB

cautions that annual PM averages “do not give an accurate indication of the

The state's

proposed 24-

hour particulate

standards may

not cover a

short enough

exposure period

to fully protect

public health.
ENVIRONMENTAL WORKING GROUP 27

seasonal nature of emissions.” (ARB 2001.) Averaging means that an area

could meet annual standards but have significantly higher PM levels for part

of the year, and acutely high levels for a few days of the year.

Shorter-term standard may be needed

A 24-hour standard may actually not be short enough to protect public health,

as there is evidence that exposure to high levels of particulates over shorter

time periods can have significant health effects. One study found that exposure

for only two hours was associated with the onset of heart attack symptoms.

(Peters et al. 2001.) ARB says it may consider shorter-term standards in the

future.

In 1993, Harvard researchers published the results of a 16-year study of 8,000

people in six cities, which found that residents of the city with the highest

levels of particulates had a 26 percent higher death rate than the people living

in the least polluted city. (Dockery et al. 1993.) An even more extensive sevenyear study conducted of more than 550,000 people in 151 metropolitan areas

found that residents of cities with the highest PM10 had a 17 percent higher

mortality rate than those residing in cities with the lowest levels. (Pope et al.

1995.) These long-term studies have convincingly shown that chronic exposure

to particulate matter increases death rates, but recent research shows that

short-term PM exposure also is associated with increased mortality.

Studies in over 200 cities worldwide – cities with significantly different climates,

racial profiles, weather patterns, pollution sources and pollution severity –

have found a consistent connection between daily PM levels and daily mortality

rates. These studies accounted for numerous other factors such as smoking,

age, poverty, weather and other pollutants. Dr. James Ware of the Harvard

School of Public Health summarized the findings: “The evidence in support of

an association between the concentration of particulate air pollution and the

mortality rate is consistent, is not affected by differences in statistical methods,

and can be generalized.” (Ware 2000.)

In assessing the health risks of a given pollutant, the standard scientific

assumption is that risks decrease as exposure rates decrease, and that no

harmful effects occur below a certain threshold. But PM does not fit this

model. Studies show that the relationship between PM concentration and

death is not a tapering curve but a straight line – that is, the health effects of

particulates are directly proportional to the level of exposure. No exposure

level, including levels below current state and federal standards, has been

found at which PM does not have a measurable effect on mortality. (Pope

2000, Daniels et al. 2000.) This has important implications for the development

of state air quality standards, which are required to determine the level above

which a pollutant is known to harm sensitive populations and incorporate a

margin of safety to protect them. (ARB/OEHHA 2001.)

“The evidence in

support of an

association

between the

concentration of

particulate air

pollution and the

mortality rate is

consistent."

 – Dr. James

Ware, Harvard

School of

Public Health.
ENVIRONMENTAL WORKING GROUP 28

Environmental pollutants do not affect everyone equally, but have greater

impact on the very young, the very old, the poor, and those with pre-existing

illnesses. The highest rates of PM-related death are among the elderly, especially

those with heart or lung diseases.

PM and SIDS

But research into PM’s effects on infants and children has found links to preterm birth or Sudden Infant Death Syndrome (crib death). Most of these studies

have been conducted outside the U.S., but indicate a 2 to 4 percent increase

in mortality for each 10 micrograms of PM10 in a cubic meter of air. (Loomis

et al. 1999, Ostro et al. 1999a.) A study of 98,000 newborns in Southern California

born between 1989 and 1993 concluded that the likelihood of pre-term birth

was significantly associated with elevated PM levels during the six weeks

before birth. (Ritz 2000.)

Some critics argue that PM-related mortality is not a major public health concern,

because most deaths are of people who are already ill and only shorten life by

days or weeks. Yet in recent years scientists who have thoroughly investigated

this notion found it wasn’t true. For instance, studies have found that out-ofhospital deaths are between two and four times more strongly related to PM

pollution than in-hospital deaths. This indicates that it is not just the critically

ill who are more likely to die on days of high PM exposure. (Schwartz 2000,

2001b.) Addressing this issue, the ARB and OEHHA say PM-related mortality

is “not the result of just a few days of life shortening . . . it appears that

significant reductions in life expectancy may be involved.” (ARB/OEHHA 2001.)

Not all particles are created equal. Research indicates that people are much

less sensitive to dust and particulates from other natural sources than industrial

emissions and auto exhaust. Two studies have found that exposure to particles

derived from motor vehicles, coal combustion, and iron and steel manufacturing

was significantly associated with daily mortality, while exposure to particles

from soil was either not associated or less significantly associated with increased

mortality. (Laden et al. 2000, Ozkaynak and Thurston 1987.) Another study

was conducted after researchers in Utah noted that hospital admissions and

deaths declined following the temporary shutdown of a local steel mill. (Pope

1989.) Scientists then exposed rats to a constant amount of particulates collected

before, during and after the mill’s closure and found that animals exposed to

particulates collected while the mill was closed showed much lower rates of

lung damage and related symptoms. (Dye et al. 2001.) The policy implications

are clear: The largest sources of particulates, such as road dust, may not be as

harmful as particulates from smaller sources such industrial emissions or auto

exhaust.

PM-related illnesses carry significant economic impacts. For example, hospital

visits for PM-induced COPD, pneumonia and cardiovascular diseases in the

population aged 65 and over and visits for pollution-induced asthma in the

population under 65 total $132 million a year (Table 3). PM-related illnesses

cause Californians to miss almost 5 million work days a year, costing the

state’s economy more than $880 million2

. Considering just these costs, the
ENVIRONMENTAL WORKING GROUP 29

price of PM air pollution in California exceeds $1 billion a year. (Table 3.) This

does not take into consideration many hospital and non-hospital costs of

other minor and serious PM-related illnesses.

If California’s air quality met the proposed PM standards, an estimated $584

million could be saved each year, cutting the costs of particulate air pollution

by more than half. (Table 3.) And if lower standards were reached, these costs

would be reduced even further. By achieving a mean ambient PM10 level of

15 micrograms per cubic meter – just 5 micrograms less than the proposed

standards – an additional $200 million would be saved each year.

Footnotes

1

 The studies on which OEHHA based their estimates of PM-related illnesses

only looked at certain age groups. OEHHA/ARB decided not to extrapolate

the results to other age groups and, instead, estimated the illness figures for

only these same age groups.

2

 The median per-day income of California residents in the year 2000 was

$180 (=46,802 / 260). (US Census Bureau 2000) The actual number of work

days lost to PM10-related illness is 4,910,652. (OEHHA/ARB 2001) The

estimated cost to the state’s economy is the product of these two numbers.

Proposed state

standards would

prevent

hundreds of

thousands of

asthma attacks

each year.
ENVIRONMENTAL WORKING GROUP 30
ENVIRONMENTAL WORKING GROUP 31

Particle Civics

Particle Civics

California has long been a national and global leader in pioneering efforts to

improve air quality to protect public health. California developed the nation’s

first vehicle emission control program in 1963, instituted the nation’s first

heavy-duty diesel truck standards in 1973, and was the first state to sell unleaded

gasoline in 1976. California has also been a trendsetter in developing healthbased ambient air quality standards that reflect the most current science

available. The existing PM10 standards are a perfect example.

In the late 1970s, ARB scientists were among the first to recognize that

particulates with diameters of 10 microns or less (PM10) posed more of a

human health risk than those with larger diameters. At that time, state and

federal air quality standards treated this highly diverse group of compounds

as one category called total solid particulates (TSP). But the ARB determined

that separate standards were needed for PM10, which took effect in 1982. It

took five more years for the U.S. EPA to follow suit, but the federal standards

were set 1.5 to three times weaker than the state standards.

Since then, entire libraries of research on particulates and health have been

published. There is no disagreement in the scientific and regulatory committees:

PM has more profound negative effects on human health than ever before

realized, and these effects are measurable at concentrations at or below current

air quality standards. This research has established that particles with diameters

less than 2.5 microns, or PM2.5, may be particularly hazardous to human

health, making the need for tougher and more comprehensive standards more

urgent.

Priority: Protecting kids

The need for a revision of California’s particulate standards was highlighted

with the passage of the Children’s Environmental Health Protection Act of

1999 (SB 25 by State Sen. Martha Escutia.) As part of the Act, the ARB and

OEHHA were required to review all existing health-based ambient air quality

standards in California to determine whether they protected infants and children,

as well as other sensitive populations, with a sufficient margin of safety. During

this review, it became clear that the current levels of particulate matter in

California were responsible for significant and measurable health effects, not

California is the

first state to

require that

air pollution

standards be

tough enough to

protect children,

rather than

 adult males.
ENVIRONMENTAL WORKING GROUP 32

only on children but the public as a whole. As result, the agencies made PM

standards the top priority for revision.

In December of 2001 the agencies proposed that California’s annual mean

PM10 standard be lowered by a third, and added a new standard for PM2.5

that is slightly more stringent than the corresponding federal standard. They

recommended leaving the short-term standard for PM10 at current levels, and

opted not to recommend establishment of a short-term standard for PM2.5.

However, after criticism from an independent scientific review panel and

pressure from the environmental community, ARB and OEHHA proposed a

short-term standard for PM2.5 that is more than twice as stringent as the

existing federal standard. (Figures 1 and 2.)

The proposed annual standards would dramatically reduce the number of air

pollution-related health problems in California. If these standards were attained,

thousands of deaths and injuries would be prevented each year: 6,525 premature

deaths, 6,903 hospital admissions for respiratory illness, 2,301 emergency room

visits for asthma, 7,835 cases of chronic bronchitis, and 338,270 asthma attacks.

(Table 9.) Overall, the number of PM10-induced illnesses and deaths would

decrease by an average of 60 percent, and PM2.5 illnesses and deaths would

be cut in half. Because these figures account only for certain illnesses and age

groups, the actual health benefits of reducing PM levels would be even greater.

How many will die?

If the standards were set at levels slightly more stringent than those being

proposed by the ARB, even more lives would be saved and illnesses avoided.

For example, if California met an annual mean PM10 standard of 15 μg/m3

and an annual mean PM2.5 standard of 10 μg/m3 an additional 1,900 premature

deaths, 2,700 respiratory hospital admissions, 850 emergency room visits for

asthma, 3,000 cases of chronic bronchitis, and 127,000 asthma attacks could

be avoided each year. Overall, PM-induced deaths and illnesses would drop

by almost 80 percent.

The consequences of moving in the other direction, toward less stringent

standards advocated by the oil and auto industries, would be deadly. EWG

analysis shows that if the annual PM10 standard was weakened only slightly

from proposed levels, to 28 μg/m3

, and the annual PM2.5 standard was set to

correspond with the federal standard of 15 μg/m3

, there would be 4,000 more

premature deaths, 3,000 more hospital admissions, 1,000 more emergency

room visits for asthma, 3,500 more cases of chronic bronchitis, and 150,000

more asthma attacks each year. The question facing the ARB board next month

is grim: How many people will California allow to die or become ill each year

from the very air they breathe?

How many

people will

California allow

to die or become

ill each year

from the very air

they breathe?
ENVIRONMENTAL WORKING GROUP 33
ENVIRONMENTAL WORKING GROUP 34 Table 9. Savings from Reducing PM-related Illnesses. PM2.5 Source: ARB/OEHHA 2001, EWG 2002, Abt 2000, US Census 2000. Ages Considered Number at current annual average PM2.5 level Cost at current level (1999 $) Number if proposed standard achieved Number fewer if proposed standard was achieved Percent fewer Dollars saved if proposed standard was achieved Additional number saved if proposed standard was tightened to 10 ug/m3 Additional dollars saved if standard was tightened to 10 ug/m3 Long-term Mortality 1 30+ 9,390 - 2,865 6,525 69% - 1,895 - Short-term Mortality All 4,011 - 2,066 1,945 48% - 573 - Chronic Bronchitis 2 27+ 11,409 N/A 5,660 5,749 50% N/A 1,612 N/A Chronic Obstructive Pulmonary Disease Hospital Admissions 3 65+ 1,243 $14,575,966 642 601 48% $7,529,519 179 $2,098,238 Pneumonia Hospital Admissions 4 65+ 1,791 $24,947,738 927 864 48% $12,914,520 258 $3,593,682 Cardiovascular Disease Hospital Admissions 5 65+ 3,173 $19,999,436 1,646 1,527 48% $10,376,736 456 $2,874,168 Asthma Hospital Admissions 6 64- 950 $16,912,004 481 470 49% $8,550,392 133 $2,366,602 Asthma Emergency Room Visits 7 64- 2,352 $703,156 1,185 1,167 50% $348,933 330 $98,670 Work Loss Days 8 64- 2,923,535 $526,236,300 175,151 1,445,535 49% $260,196,300 354,479 $63,806,290 Total $603,374,599 $299,916,400 $74,837,650 PM10 Ages Considered Number at current annual average PM10 level Cost at current level (1999 $) Number if proposed standard achieved Number fewer if proposed standard was achieved Percent fewer Dollars saved if proposed standard was achieved Additional number saved if proposed standard was tightened to 15 ug/m3 Additional dollars saved if standard was tightened to 15 ug/m3 Long-term Mortality 9 30+ 7,470 - 978 6,492 87% - N/A - Short-term Mortality All 4,063 - 1,772 2,291 56% - N/A - Chronic Bronchitis 10 27+ 13,530 N/A 5,696 7,835 58% N/A 2,902 N/A Chronic Obstructive Pulmonary Disease Hospital Admissions 11 65+ 2,115 $24,792,990 923 1,192 56% $10,815,492 463 $5,427,286 Pneumonia Hospital Admissions 12 65+ 3,061 $42,639,263 1,340 1,721 56% $18,664,007 671 $9,346,359 Cardiovascular Disease Hospital Admissions 13 65+ 5,452 $34,362,621 2,395 3,057 56% $15,096,981 1,195 $7,532,085 Asthma Hospital Admissions 15 64- 1,624 $28,904,937 692 933 57% $12,311,563 346 $6,156,724 Asthma Emergency Room Visits 15 64- 3,992 $1,193,527 1,691 2,301 58% $687,999 850 $254,150 Work Loss Days 16 64- 4,910,652 $883,917,360 254,466 2,814,815 57% $506,666,700 953,659 $171,658,534 Total $1,015,810,698 $564,242,742 $200,375,138
ENVIRONMENTAL WORKING GROUP 35

Notes - Table 9

1) The reason why the number of PM2.5-related deaths is higher than the

number of PM10-related deaths even though PM2.5 particles are a subset of

PM10 particles is related to the study which ARB/OEHHA based their calculations of long-term mortality. This study (Krewski et al. 2000) found longterm mortality to be assocaited only with the fine (PM2.5) fraction of

PM10. Although the other major long-term mortality study (Dockery et al.

1993) did find an association between chronic exposure and mortality, ARB/

OEHHA decided to based their calculations on the Krewski et al. (2000)

study. See ARB/OEHHA 2001 for futher details.

2) The costs related to chronic bronchitis could not be calculated.

3) Hospital charge cost only. Mean hospital stay is 6.02 days with a mean

charge of $11,722 (1999 dollars). (Abt 2000)

4) Hospital charge cost only. Mean hospital stay is 7.01 days with a mean

charge of $13,929 (1999 dollars). (Abt 2000)

5) Hospital charge cost only. Mean hospital stay is 5.44 days with a mean

charge of $17,794 (1999 dollars). (Abt 2000)

6) Hospital charge cost only. Mean hospital stay is 3.03 days with a mean

charge of $6,303 (1999 dollars). (Abt 2000)

7) The average asthma ER visit cost is $299 (1999 dollars). (Abt 2000)

8) The median per-day income of California residents in the year 2000 was

$180. (US Census 2002)

9) The number of PM10 related deaths at an annual average of 15 ug/m3 was

not calculated because no studies have been done on mortality where PM10 is

less than 18; as a result OEHHA/ARB uses 18 ug/m3 as background level.

10) The costs related to chronic bronchitis could not be calculated.

11) Hospital charge cost only. Mean hospital stay is 6.02 days with a mean

charge of $11,722 (1999 dollars). (Abt 2000)

12) Hospital charge cost only. Mean hospital stay is 7.01 days with a mean

charge of $13,929 (1999 dollars). (Abt 2000)

13) Hospital charge cost only. Mean hospital stay is 5.44 days with a mean

charge of $17,794 (1999 dollars). (Abt 2000)

14) Hospital charge cost only. Mean hospital stay is 3.03 days with a mean

charge of $6,303 (1999 dollars). (Abt 2000)

15) The average asthma ER visit cost is $299 (1999 dollars). (Abt 2000)

16) The median per-day income of California residents in the year 2000 was

$180. (US Census 2002)
ENVIRONMENTAL WORKING GROUP 36
ENVIRONMENTAL WORKING GROUP 37

Particle Civics

Who’s Against

Clean Air?

Lobbyists for the petrochemical industry, automakers and engine manufacturers

have mounted a major campaign against the PM standards proposed by the

Air Resources Board and Office of Environmental Health Hazard Assessment.

The dirty-air lobby includes the Alliance of Auto Manufacturers, representing

13 U.S. and international automakers; Western States Petroleum Association,

representing 36 oil companies; and the Engine Manufacturers Association,

representing 27 companies. Individual corporations include ExxonMobil,

General Electric and BP (formerly British Petroleum) ranked by Forbes as the

second, third and fourth most powerful corporations in the world.

According to records filed with the California Secretary of State, 22 industry

associations and individual companies opposed to tougher particulate standards

spent more than $7.5 million in 2001 on lobbying at the State Capitol. (Table

10.) Most of these associations and companies have full-time lobbyists in

Sacramento or are represented by one or more lobbying firms, some of whom

employ whole teams of lobbyists. Their lobbying activity is in addition to

hundreds of thousands of dollars in campaign contributions to state politicians

made by the associations and companies each year. Just three members of the

Western States Petroleum Association – BP, Occidental Petroleum and Chevron

Texaco–– collectively gave $175,000 to Gov. Gray Davis in 2000-2001. (CalAccess 2002.)

The truth behind the smokescreen

Here’s a sampling of their arguments against cleaner air, and the truth behind

the smokescreen:

♦ The Alliance of Auto Manufacturers and Engine Manufacturers

Association claim the proposed tougher standards will not “result

in any greater protection of public health than the current

California standards.” (AAM 2002.) But the peer-reviewed risk

assessment by state scientists found that attaining the

“recommended standards would result in a reduction of . . .

about 3 percent of all mortality in the population above age

30.” (ARB/OEHHA 2001.)

♦ According to the Western States Petroleum Association, “as much

or more public health benefit would be gained from uniform

reduction targets than from a single statewide standard.” (WSPA

Oil companies

and automakers

opposed to

cleaner air gave

Gov. Davis

$175,000 in

the current

election cycle.
ENVIRONMENTAL WORKING GROUP 38

2002.) But because the heaviest particulate pollution is found

in lower-income communities of color, such a policy would

perpetuate existing environmental inequities”– as if people who

live in highly polluted areas have less right to clean air.

♦ Ford Motor Co. says the proposed standards are “impossibly

stringent . . . with practically no hope of attainment.” (Ford

2002.) It is hard to take this claim seriously when the auto

industry’s estimates of the cost of complying with other recent

air quality regulations have been inflated by a factor of 14.

(Browner 1997.)

The attack on California’s proposed particulate standards is a rerun of the

same special interests’ efforts to derail tough standards at the federal level.

In 1996, the U.S. EPA proposed for the first time to regulate PM2.5, after

research had shown strong links between fine particles and death. The EPA

proposed to cut allowable levels of PM2.5 in half, saving an estimated 35,000

lives a year nationwide. In California those standards would have saved an

estimated 2,500 lives. In reviewing the EPA’s 1997 proposal, the Air Resources

Board went further, recommending an even tougher PM2.5 standard that would

have saved an estimated 3,000 to 4,000 additional lives in the state.

Even before the EPA and ARB announced their proposals, more than 650

industry associations and companies banded together as the Air Quality

Standards Coalition. The coalition included the National Association of

Manufacturers, American Petroleum Institute, American Automobile

Manufacturers Association, Chemical Manufacturers Association, Edison Electric

Institute, National Mining Association, American Forest and Paper Association,

and American Trucking Association.

Goodbye to barbecues?

The coalition spent $1.5 million on a nationwide lobbying and misinformation

campaign, and millions more on industry-funded “sound science” to undermine

the peer-reviewed science relied on by the EPA. They spread exaggerated

claims about how the proposed standards would impact the American way of

life –for example, forcing an end to backyard barbecues. (Skrzycki 1996) A

fake “grassroots” group called Citizens for a Sound Democracy targeted AfricanAmericans and Latinos, warning that the cost of new standards was too high

for small minority-owned businesses. (Washington Post 1996.)

To the contrary, in 1997 EWG found that residents of communities of color in

California would benefit the most from tougher PM standards, because people

in communities of color were nearly three times more likely to breathe

dangerous levels of PM pollution than Californians living in predominantly

white communities. Based on then-current population and pollution data,

residents of communities of color had a 54 percent chance of breathing unsafe

levels of particulates, compared to a 19 percent chance for predominantly

white communities. (EWG 1997a.)

Residents of

communities of

color, who are

more likely

to breathe

dangerous levels

of particulate

pollution, would

benefit most

from cleaner air.
ENVIRONMENTAL WORKING GROUP 39

After the standards were adopted by the Clinton Administration, the American

Trucking Association challenged them in court, claiming that EPA had

overstepped its authority in setting the regulations and that the agency should

consider the cost of compliance as well as the benefits to public health. ATA’s

arguments were dismissed by the U.S. Supreme Court in 2001. The ruling

stated that the law clearly established the agency’s right to set standards and

that the Act “unambiguously bars cost considerations.” But the Supreme Court

also sent parts of the case back to the U.S. Court of Appeals for clarification. In

March 2002 the appeals court affirmed its ruling that “EPA must err on the side

of caution – setting the [standards] at whatever level it deems necessary and

sufficient to protect the public health with an adequate margin of safety, taking

into account both the available evidence and the inevitable scientific

uncertainties.”

The unanimous appeals court ruling ended five years of counterattack by the

opponents of cleaner air. In that period, according to EPA’s estimates, 175,000

Americans died from PM pollution whose lives would have been saved or

extended if air quality goals represented by the proposed standards had been

achieved.

Table 10. Opponents of new PM standards spent almost $7.5 million to lobby

against cleaner air in 2001.

Source: Compiled from lobbying and campaign finance reports as filed with the California

Secretary of State. Available at http://CAL-ACCESS.ss.ca.gov

Lobbying 

Expenditures 

2001

Contributions 

to Gov. Davis, 

current 

election cycle

Western States Petroleum Association $2,137,100

BP America $1,253,634 $80,000

Chevron Texaco $760,456 $35,000

General Motors Corporation $549,434

Equilon Enterprises $521,600

Ford Motor Company $418,742

Phillips Petroleum $396,143

General Electric $255,774

Nuevo Energy Company $174,207

Alliance of Automobile Manufacturers, Inc. $161,790

Aera Energy LLC $151,466

Occidental Petroleum $135,225 $60,000

Ultramar Diamond Shamrock Corp. $120,983

Exxon Mobil $112,937

Toyota Motor Sales, U.S.A., Inc. $85,673

DaimlerChrysler Corporation $51,213

Kinder Morgan Energy Enterprises $44,921

Caterpillar Inc. $41,735

Deere and Company $36,348

Nissan North America $25,156

Venoco Inc. $3,000

TOTAL $7,437,537 $175,000
ENVIRONMENTAL WORKING GROUP 40
ENVIRONMENTAL WORKING GROUP 41

Particle Civics

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