| Dear
EarthTalk: I know of issues associated with
the Earth’s ozone layer, but what is “ground
level ozone” and why is that a problem?
-- D. Goetz, Palm Beach, FL
Ozone
(O3) is a colorless gas formed when three atoms of oxygen
bond together. About 90 percent of the Earth’s ozone
forms naturally in the stratosphere, dozens of miles above
ground. It forms the protective layer that shields us from
overexposure to the sun’s radiation, and is therefore
considered “good” ozone.
The
rest of the ozone found on Earth occurs at ground level,
and forms when nitrous oxides and various “volatile
organic compounds’ (VOCs)—originating with car
exhaust, industrial emissions, chemicals and gasoline vapors,
as well as some natural sources—bond together in the
presence of sunlight.
Ground
level ozone, or “bad” ozone, is a key component
of smog, which wreaks havoc on human health and the environment,
especially in urban areas. The U.S. Environmental Protection
Agency (EPA) reports that exposure to even relatively low
concentrations of ground-level ozone for extended periods
(several hours) can significantly reduce lung function and
cause respiratory inflammation in normal, healthy people.
Symptoms can include chest pain, coughing, nausea and congestion.
For people with asthma and other respiratory illnesses,
exercising in ozone-rich air can be deadly. Repeated exposure
to high levels of ozone for several months or more can produce
permanent structural damage in the lungs.
Beyond
its effects on our health, the EPA estimates that pollution
from ground-level ozone is responsible for nearly $2 billion
in agricultural crop yield losses in the U.S. alone each
year. The pervasive gas has also been shown to damage forests
in California and the eastern U.S. and to contribute to
global warming.
Under
the mandate of the Clean Air Act, the EPA is charged with
monitoring and limiting the amount of ground-level ozone
in urban areas, and issuing warnings when smog levels are
above its standard of 0.12 parts per million. But new studies
indicate that ground-level ozone causes adverse health effects
at even lower concentrations. And, according to the EPA,
even rural areas suffer increased ozone levels, because
wind carries ozone and the pollutants that form it hundreds
of miles away from their original sources. As a result,
the EPA is reviewing whether revisions to ozone standards
and policies are warranted.
High
concentrations of ground-level ozone are not as common in
Canada, but three urban regions—British Columbia’s
Lower Fraser Valley, the Windsor-Québec City Corridor
and the Southern Atlantic Region that includes New Brunswick
and Nova Scotia—do suffer several “bad air days”
each year. The Canadian government, through its own Clean
Air Act, has even stricter standards for exposure to ground-level
ozone than in the U.S., though enforcement is not as big
a priority given the smaller scope of the problem there.
To
help minimize ground-level ozone, avoid car trips and the
use of power lawn equipment during especially hot or windless
days. Paints and solvents, most which off-gas VOCs that
create ozone and form smog, are also best to steer clear
of with hot summer temperatures coming on strong. Those
concerned about their respiratory health should follow local
weather sources, most which post smog alerts.
CONTACTS:
U.S.
EPA Ground-Level Ozone Information; Canada’s
Clean Air Act.
Dear
EarthTalk: Are there organizations that specifically
address the environmental challenges faced by poor and minority
communities?
-- Bill Macomber, Ann Arbor, MI
When sociologist
Robert Bullard began uncovering the proximity of hazardous
waste sites to minority neighborhoods across the American
South during the course of his graduate research in the
1980s, the “environmental justice” movement
was born. In the intervening two decades, environmental
and human rights advocates around the U.S. and the world
have launched thousands of nonprofit community groups to
battle so-called “environmental racism”—whereby
otherwise distressed and poor minority communities are disproportionately
exposed to the brunt of industrial pollution in their own
backyards.
Environmental
justice is fundamentally a local issue, but several national
groups have devoted considerable resources to righting wrongs
and helping communities defend their rights to clean air
and water. Perhaps the best known is the Center for Health,
Environment and Justice (CHEJ), founded by Lois Gibbs, the
mom-turned-activist who in the early 1980s got authorities
to shut down and remediate the Love Canal district of Niagara,
New York, where buried industrial waste was causing serious
health problems. CHEJ has since fought alongside thousands
of communities to get toxic sites cleaned up and obtain
restitution.
In other ongoing
efforts, Environmental Defense’s “Living Cities”
program pairs teams of scientists, lawyers and economists
with local groups working to resolve environmental health
issues in minority population centers. And the Natural Resources
Defense Council (NRDC) conducts studies, produces reports
and policy analyses and mounts campaigns and lawsuits on
various environmental justice issues, with a recent focus
on helping the victims of Hurricane Katrina. Another big
player is the Earthjustice Legal Defense Fund, a nonprofit
public interest law firm that has championed several high-profile
environmental justice cases since it began as the Sierra
Club Legal Defense Fund in 1971. Protecting farm worker
communities from dangerous pesticides is a current focus
area.
Those with environmental
justice issues needing attention can contact one of these
groups or a regional one that can help size up potential
toxic threats and provide assistance on what to do. The
Southwest Network for Environmental and Economic Justice,
the New York City Environmental Justice Alliance, the Environmental
Law and Policy Center of the Midwest and the San Francisco
Urban Institute are all great resources, as are Robert Bullard’s
Environmental Justice Resource Center, based at Clark Atlanta
University, and the Environmental Research Foundation, located
in New Jersey.
The U.S. Environmental
Protection Agency (EPA) has also begun to take these issues
seriously and in 1992 created its Office of Environmental
Justice to integrate environmental justice into EPA policies
and programs. Community groups can apply for EPA grants,
and an EPA internship program places students directly into
communities to assist local groups in addressing local environmental
and public health issues.
CONTACTS:
CHEJ;
Earthjustice;
Southwest
Network for Environmental and Economic Justice; San
Francisco Urban Institute; Environmental
Law and Policy Center; New
York City Environmental Justice Alliance; Environmental
Justice Resource Center; Environmental
Research Foundation.
|
