Rachel Carson, DDT, and air pollution

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Rachel Carson, DDT, and air pollution
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Interdisciplinary perspectives

• Natural sciences (biology, chemistry, etc.)
• Medical sciences (especially epidemiology, the
  study of disease and risk factors)
• History
• Ethics
• Economics
• Writing and story-telling
• National and international perspectives

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Historical perspectives

• 1962 Silent Spring
• 1969 Natl. Environmental Policy Act (requiring
  Enviro Impact Statements)
• 1970 Creation of EPA
• 1970 Clean Air Act
• 1972 Clean Water Act
• 1972 U.S. bans DDT
• 1973 End. Species Act

Rachel Carson (1907-1964)
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Silent Spring is a metaphor referring to

• Aquifers running dry
• An imaginary polluted city near Washington DC
• Loss of songbirds

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According to Tina Rosenberg, Rachel Carson didnt
consider

• DDT impacts on farmworkers
• DDT impacts on malaria
• DDT impacts on wildlife

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Natural Science Evolution 1 (Sharing)

• To what extent can we design chemicals that harm
  insects without harming humans?
• To what extent do insects and humans share
  biological processes?
• The organic phosphorus insecticides destroy
  enzymes Their target is the nervous system,
  whether the victim is an insect or a warm-blooded
  animal. (p. 18)

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Natural Science Evolution 2 (Resistance)
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Natural science Bioaccumulation

• Each food chain step involves 90 loss of
  energy, e.g., 1 pound of snake comes from 10
  pounds of frog.
• If 0 of chemicals are lost, then 1 pound of
  snake contains the chemical load of 10 pounds of
  frog.

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PBDEs (compounds used in flame retardants) in
human breast milk
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Epidemiology Scientific detective work about
diseases and their causes

• Germ theory of disease vs. miasma theory
  (bad air / mal aire / malaria)
• John Snows map of London in 1854, showing
  cholera deaths
• Clustered around Broad Street pump!

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Annual change in incidence and death rates,
1994-2003 (cancer.gov)
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Generating and testing hypotheses about cancer

• What could cause cancer incidence rates to
  increase or decrease?
• What could cause cancer death rates to increase
  or decrease?
• How to test hypotheses about cancer?
• These are not academic questions!
• Breast cancer 1 in 8 will get it, 1 in 33 will
  die from it.
• Prostate 1 in 6 will get it, 1 in 34 will die
  from it.
• PS. Conduct self-exams for breast, testicular
  cancers!

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Epidemiology Scientific detective work about
diseases and their causes

• Establishing cause-and-effect links between
  pollution and health or other impacts is hard!
• Precautionary principle? When an activity raises
  threats of harm to human health or the
  environment, precautionary measures should be
  taken, even if some cause-and-effect
  relationships are not fully established
  scientifically. (Wingspread Statement, 1998)

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Case study Toxics http//www.epa.gov/tri/
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Case study Toxics

• Only a quarter of the 82,000 chemicals in use in
  the U.S. have ever been tested for toxicity. Each
  year industry seeks to add 1,700 new compounds.
• How (if at all) to apply precautionary principle?
  (Retroactively?)
• Is the absence of evidence the evidence of
  absence?
• Ignorance is not a solvable problem, but rather
  an inescapable part of the human condition. The
  advance of knowledge always carries with it the
  advance of some form of ignorance. (David Orr)

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Health effects research options

• Animal toxicology and in vitro methods
• Controlled hard to extrapolate
• Controlled human studies
• Controlled small samples short exposures
• Analysis of the real world
• Asks the right question
• Estimates health outcomes and exposures
• Confounding variables?

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A brief history of air pollution, mostly focused
on the U.S.

• Air is a basic necessity for life (without O2 we
  get brain damage in 3 minutes)
• Lungs are readily irritated by noxious gases
  (e.g. O3, SO2, smoke, etc.)
• Lungs are also a good conduit for absorption into
  bloodstream of toxics such as Pb lead, CO not
  CO2!, benzene, etc.
• Due to low mass of earths atmosphere and
  sometimes poor dispersion, air can be readily
  polluted.

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History of major air pollution incidents

• Belgium, 1930-- 63 deaths
• Donora, PA,1948--20 deaths
• London, 1952--4000 deaths
• New York, 1966--166 deaths.

These incidents all occurred in heavily
industrialized regions, under severe
meteorological conditions (strong inversions with
poor ventilation).
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London Killer Fog
December 1952 A toxic mix of dense fog and sooty
black coal smoke killed thousands of Londoners in
four days. It remains the deadliest environmental
episode in recorded history.
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(No Transcript)
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The Clean Air Act (CAA)

• Used as a model for laws in other countries.
• Original in 1970, with major revisions in 1977,
  1985, 1990, 1995 to deal with toxics and
  stratospheric ozone in addition to 6 originals
• CO (not CO2!) and Pb (Lead) and SOx.
• NOx and VOCs (Volatile Organic Compounds), which
  produce ground-level ozone (smog)
• Particulate matter (rocks) PM10, PM2.5

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PM10 and PM2.5
The health risks from particulates are due in
part to the small size. The smaller the size, the
bigger health risk. PM2.5 stays in the air much
longer than PM10, taking days to weeks to be
blown away.
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Acute versus chronic health effects

• Acute effects are those that appear to be
  associated with air pollution on the same day or
  1-4 days prior to the outcome
• Chronic health effectssometimes called
  longitudinalare over 10-20 years or more. In
  children and young adults this can be a lifetime
  exposure.

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Good news Many local air pollutants have
decreased over time
Source U.S. EPA
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even as populations and economic activity have
risen!
Source U.S. EPA
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More good news The Clean Air Act passes a
Cost-Benefit Analysis!

• In the 1990 CAA amendments, congress required EPA
  to conduct a cost-benefit analysis on the CAA
• Final Report to Congress on Benefits and Costs
  of the Clean Air Act, 1970-1990
• Annual Costs 25 billion (mainly compliance
  costs)
• Annual Benefits 1.1 trillion (range 0.3-2.5
  trillion)
• Mainly avoided deaths, avoided hospitalizations
  and avoided lost IQ points in children)
• A no brainer...

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Bad news Air pollution is still a problem in the
U.S.

• The CAA specifies that EPA should set air
  standardscalled the National Ambient Air Quality
  Standards (NAAQS)in order to protect the most
  sensitive members of the public with an adequate
  margin of safety.
• Costs or other economic considerations are not to
  be considered.
• NAAQS should be re-evaluated by EPA every 5 years
  to ensure they are consistent with best
  scientific data. This leads to a ratchet
  effect.

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Non-attainment areas for 8-hour O3 standard
Currently, about 100 million people in the US
live in areas that dont meet the O3
standard. Note that in 2007, EPA has proposed a
new lower (tougher) O3 standard. Final rules
will be announced in 2008.
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PM2.5 Non-attainment areas
Orange Areas that exceed only the annual std
(15 ug/m3). Yellow Ares that exceed only the 24
hour std (65 ug/m3). Red Areas that exceed both.
Currently, 50 million people in the US live in
areas that violate the PM2.5 standard. By one
estimate, there are 64,000 premature deaths in
the US due to PM, at levels above and below the
standard.
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New PM2.5 Non-attainment areas (2007)
Orange Areas that exceed only the annual std
(15 ug/m3). Yellow Ares that exceed only the 24
hour std (35 ug/m3). Red Areas that exceed both.
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International perspectives

• In her 297 pages, Rachel Carson never mentioned
  the fact that by the time she was writing, DDT
  was responsible for saving tens of millions of
  lives, perhaps hundreds of millions. DDT killed
  bald eagles because of its persistence in the
  environment. Silent Spring is now killing African
  children because of its persistence in the public
  mind. (Rosenberg 2004)

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We should use DDT on malaria

• Strongly Agree
• Agree
• Neutral
• Disagree
• Strongly Disagree

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Beijing Smog
According to the World Bank, 16 of 20 of the
worlds most polluted cities are in China.
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Wood smoke as a pollutant
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Wood smoke as a pollutant
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Wood smoke as a pollutant
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Global Air Pollution Science and Implicationsby
Dan Jaffe, UW-Bothell
Research team (R to L) Will Hafner, Duli Chand,
Phil Swartzendruber, Mary Howisey, Dave
Reidmiller, Jeremy Smith and Dr J (not shown
Emily Fischer)
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Most air pollution is from local sources, but as
we move to lower standards, background air
becomes more important
Background air
Figure EPA Atmospheric Deposition Handbook, 2001.
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Mean wind vectors for April700 mb (10,000 feet
elevation)
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PHOBEA Study Area
CPO
Aircraft profiles
Photochemical Ozone Budget of the Eastern North
Pacific Atmosphere.
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The view from Cheeka Peak
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Cheeka Peak 10 meter Sampling Tower
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Vertical Profiles using Beechcraft Duchess

• Twin (piston) engine aircraft
• Unpressurized cabin
• Maximum flight altitude 6km, 4 hours useable
  flying time
• Maximum instrument payload 240 kg
• Maximum instrument volume 1.5m3
• Maximum power 1 kw
• Available locally (Northway Aviation, 20min from
  lab)
• 250/hour including pilot.

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How important is background air?
The blue bars show the mean conc. of O3 and PM2.5
in the air arriving to Wash. State from the
Pacific.
Current O3 std
New O3 std
Current PM std
New PM std
Background concentrations are partly natural and
partly due to global anthropogenic sources.
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TOMS Aerosol Index (AI) for mid-April 2001
April 8, 2001
Satellites give useful information on large
transport events, however this data is
qualitative, lacks altitude and chemical
information and is often obscured by clouds. To
put this in perspective, we have identified about
15 transport events, but only 3 have been
identifiable with satellite data. The April 2001
dust event was a biggie
April 12, 2001
April 14, 2001
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How did the April 2001 Asian dust episode
influence air quality in several urban areas of
the U.S.?
Old std
New std
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More bad news Global warming may worsen
ground-level ozone (smog)
Source Jane Koenig
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But overall, what Tom Lehrer wrote is (mostly) no
longer true

• If you visit an American city
• You will find it very pretty
• Just two things
• of which you must be aware
• Dont drink the water
• and dont breath the air!