Preventing Exposures to Hazardous Air Pollutants
April 14, 2011
essay is in response to: What is the most important achievement we've gained through air pollution management? What remains to be done to safeguard public health from air pollution?
implementation of the Clear Air Act of 1970 people across the country breathe
healthier air because of much lower concentrations of carbon monoxide, acidic
gases of sulfur and nitrogen, lead, particulates, and ozone. Furthermore,
ecosystems in the eastern United States are recovering from the effects of
acidic precipitation. Why was it so successful?
The Clean Air
Act of 1970 allowed for the setting of ambient air standards for the six
criteria pollutants: carbon monoxide, lead, particulates, oxides of sulfur and
nitrogen, and ozone. By law, areas that did not meet the ambient air quality
standards had to control such emissions. Industry was forced to drastically
reduce emissions of these gases which resulted in greatly improved public and
ecosystem health. Several benefit-cost analyses have shown greater than a 10 to
1 ratio of public health benefits per pollution prevention costs. This is an
excellent outcome for public health made possible by the ability of the
government to regulate polluters.
regulation of polluters was not achieved without political push-back, and the
biggest impediment to continuing to protect the public from air pollution
related disease is the ongoing war between those who see a limited role for
government and those depending on the government to protect them from unhealthy
air. This war is meticulously documented in Merchants
of Doubt (2010) by Naomi Oreskes and Erik M. Conway, and it is worth
looking at one of the battles as it illustrates what efforts to improve public
health through better air quality are up against.
Conway document government moves to alert the public that cigarette smoking
caused cancer. By the 1950s, cigarette smoke was known, in public health
circles, to cause cancer. If this fact was accepted by the health community,
why would anyone outside the tobacco industry try to dilute this message? Timing
explains much of this story. The country was in the grips of the cold war and a
few prominent scientists with strong convictions that government regulation of
personal choice would lead to communism used their reputations to cast doubt on
this fact. Driven by their ideological fervor, these scientists used their
political clout to support misinformation from the tobacco industry to
effectively delay for years the Surgeon General’s warning on cigarettes.
battle has been waged with similar tactics but also with the help of well
funded think tanks to stop the regulation of air pollutants such as: acidic
gases from power plants (acid rain), refrigerants (ozone hole), and second hand
cigarette smoke. This battle continues today with the same mix of
anti-regulatory players attempting to cast doubt on the relationships between
greenhouse gas emissions and climate change.
powerful forces, how was the Clean Air Act passed? President Nixon pushed for
its passage to silence opposition from the environmental movement which helped
his re-election in 1972. Regardless of the politics, credit for cleaner air
countrywide should go to the Clean Air Act of 1970. The act allowed for the regulation
of emissions from all sorts of polluters which has greatly reduced air
pollution and simultaneously improved public health. However, the fight to
reduce the impacts of air pollution on public health is not over.
scientifically-based message to the global community on how air pollution
impacts the short- and long-term livability of the planet is needed. What must
the global community hear? Greenhouse gas emissions are causing drastic changes
in global climate. Furthermore, emissions of hazardous air pollutants (HAPs)
are degrading public health locally and worldwide.
How these two
air pollution issues will impact public health differ greatly in magnitude and
scale. We must limit emissions of greenhouse gases to slow sea level rise,
reduce disruptions in global food production, and secure the availability of
potable water worldwide. The potential changes in habitable land, food
production, and potable water could set in motion a cascade of human displacement,
malnutrition, and disease that will impact all corners of the globe. Effective
regulation of greenhouse gases will be difficult because of the global nature
of the sources and the enormous costs. Proper decisions can only be made from
an informed debate of the issues. Unfortunately, the disinformation war on the
relationships between greenhouse gas emissions and climate change is already
well engaged and the battle tactics by those in opposition are better funded
than ever. If human impacts on climate change aren’t addressed soon, the
benefits from control of emissions of HAPs will be inconsequential.
recognizing this, it is still important to move forward on reducing the
public’s exposure to air pollution. People are exposed to air pollutants in
many ways. The most direct exposure is breathing contaminated air. Furthermore,
air pollutants can be taken into the body by eating foods contaminated by
airborne compounds, by drinking contaminated water, by ingesting contaminated
soil, or by skin contact with contaminated soil, dust, or water.
Environment Protection Agency has designated 188 compounds as HAPs. These
compounds have the capacity to cause cancer, birth defects, heart and
respiratory disease, and harm to the environment. The sources of HAPs come
mainly from human activities and sporadically from natural sources such as
forest fires. Emissions from mobile sources (cars, trucks, trains, etc.),
stationary sources (large industrial polluters), and area sources (small
businesses, cleaning products, paints, small gas engines) contain HAPs. What
can be done to protect the public from unhealthy levels of HAPs?
education for self-protection should be part of the solution. Presently, the
EPA is working with state, local, and tribal governments to diminish the
release of HAPs into the environment. Because of the complexity of setting
ambient air quality standards such as was done with the six criteria
pollutants, EPA has chosen to reduce emissions of HAPs through rules for
specific sources such as: mobile sources (cars and trucks), area sources
(household products, small engines, small businesses), and point sources (large
industry). The rules limit the amount of HAPs released by a product or process.
This form of regulation reduces the amount of HAPs released into the air. However,
those using polluting products or living next to a source of HAPs have a
greater burden than those using safer products and living further away from
Every day we
make personal choices that affect our exposure to and generation of HAPs. A
good example of this is where we choose to live, work, and recreate. Highly
used roads produce unacceptable levels of HAPs such as benzene (cancer) and
fine particulates (cancer and respiratory disease). Thus, not only those living
near the road but drivers experience unacceptable exposures to HAPs. Clear
solutions to this are less driving, cleaner cars and trucks, and alternative
forms of transportation.
calling for higher fuel efficiencies for vehicles and cleaner power generation
would do much to protect the public from HAPs. In particular, coal-fired power
plants should be compelled to drastically reduce emissions of mercury. Mercury
is being distributed worldwide by the burning of coal and it bioaccumulates in
certain foods. The EPA has issued warnings on fish consumption as a result of
mercury pollution. This issue illustrates the complexity of regulation of HAPs.
Coal is a cheap source of power and is found in abundance but its use is
contributing to public health problems that are mounting with the real
consequences and costs only coming due in the .
Any and all
new regulations on industry or personal choices will be met with strong
political opposition of the sort described above. We as a society need to
promote a rational dialogue on these issues to create options to mitigate the
damage that is taking place now and will accelerate in the future.