Today’s post is by Mel Peffers, a project manager in the Living Cities program at Environmental Defense Fund.
May 6 was World Asthma Day. Since car exhaust can lead to asthma as well as global warming, we thought it would be a good day to highlight the importance of not idling your car or truck engine.
What makes idling especially bad for health is that drivers tend to idle in gathering places – by sidewalks, schools, playgrounds, homes, and offices. Breathing in pollution close to the source is more dangerous than farther away.
Take a look at the evidence.
Tailpipe Exhaust May Cause Asthma
Tailpipe exhaust from both gasoline- and diesel-burning vehicles contains the pollutants that produce ozone when combined with sunlight and heat. Ozone occurs mostly during the summer months. A warming planet means more hot days, and thus more ozone.
Breathing in ozone irritates and inflames your lungs, and repeated exposure can reduce lung function. There’s a lot of evidence that ozone makes asthma worse. But the Children’s Health Study in California found evidence that ozone causes asthma. The study also found that children can suffer irreversible lung damage as adults from breathing smog.
On top of that, diesel exhaust contains particulate matter (soot). This has long been known to cause a variety of health problems, including aggravated asthma (see CARB report on health effects [PDF]). But as with ozone, there is evidence that diesel exhaust particles may cause asthma, and not just worsen it.
California kids aren’t the only ones to suffer from tailpipe-induced asthma. A 2005 NYU Medical Center study showed that asthma symptoms among children in the South Bronx doubled on high traffic days.
Conversely, reducing ozone can improve asthma rates. During the 1996 Summer Olympics in Atlanta, the city closed downtown to private cars for 17 days. During this time, daily peak ozone levels dropped more than a quarter and hospitalizations for asthma fell by almost one-fifth.
Fight Global Warming, Save Money
There’s no reason to idle your vehicle engine. As I explained my previous post:
- Today’s engines don’t need a warm-up period.
- If you’re stopped for more than 10 seconds, it uses more gasoline to idle than to restart.
Many cities, including New York, have laws against idling, but they’re rarely enforced. We need better enforcement, but we can make a difference with our own actions and behavior.
So in honor of World Asthma Day, switch off that idling engine. You’ll curb global warming pollution, save money on gasoline, and help everyone to breathe better.
Steve Hengsperger
When using the terms smog and ozone in the same sentence, there needs to be some clarification. Mother Nature produces ozone naturally to try and clean and protect the earth. The ozone layer is way up there and without it we would not be able to go outside. At ground level, ozone is everywhere already. It is inside our homes and it is in our neighbourhoods. It is created when UV rays split oxygen molecules which is a natural process. The extra oxygen atoms link with oxygen molecules and become highly unstable. This unstable extra oxygen atom is there to ‘clean’ our earth. On a hot day, all of the emissions from your car are not able to rise up as high in the atmosphere and it is these VOCs and carbon monoxide that cause asthma, Mother Nature is just creating ozone to help break it all down.
Ozone in air is considered a mild lung irritant, yet none of us ever complain when we take a whiff coming out of our local photocopier.
It is also used extensively in water as a sanitizer. Your large theme park water slides almost all use ozone exclusively. If you are the host city for the Olympics, the water venues MUST be ozone. Why would we let our Olympic swimmers swim in this water, breath it and probably even drink it if it was that dangerous?
Mel Peffers
EPA has put together a very informative brochure on ground-level ozone, sometimes referred to as smog. It’s available at: http://airnow.gov/index.cfm?action=static.brochure. Simply put, ozone up high is good, ozone down low, where we breathe, is bad.
• Good Ozone. Ozone occurs naturally in the Earth’s upper atmosphere — 10 to 30 miles above the Earth’s surface — where it shields us from the sun’s harmful ultraviolet rays.
• Bad Ozone. In the Earth’s lower atmosphere, near ground level, ozone is formed when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants and other sources react chemically in the presence of sunlight. Ozone pollution is a concern during the summer months when the weather conditions needed to form ground-level ozone — lots of sun, hot temperatures — normally occur.
Ground-level ozone is very bad for lungs and respiratory health. From EPA’s web site (http://www.epa.gov/iaq/pubs/ozonegen.html):
“Healthy people, as well as those with respiratory difficulty, can experience breathing problems when exposed to ozone. Exercise during exposure to ozone causes a greater amount of ozone to be inhaled, and increases the risk of harmful respiratory effects. Recovery from the harmful effects can occur following short-term exposure to low levels of ozone, but health effects may become more damaging and recovery less certain at higher levels or from longer exposures (US EPA, 1996a, 1996b).”
Volatile organic compounds (VOCs) and oxides of nitrogen (NOx) react with sunlight creating ozone (O3). For a description of this process, see: http://www.duke.edu/web/nicholas/bio217/akcarr/formation.htm.
Not all natural breakdown processes immediately result in less toxic results; when you add VOCs into the process, ozone buildup can occur. Mother Nature is not always benign and gentle in her cleansing approaches. In urban settings or dense, high traffic zones, ozone builds up during the day with some vertical mixing and then gets transported and dispersed during the nighttime. Summertime is a particularly bad time for ozone generation due to longer periods with sunlight exposure. When meteorological conditions don’t allow for dispersion and nighttime recovery from daytime ozone generation, the result can be even more dangerous ozone buildup and plumes, which can drift into rural areas. (See Nashville July 1995 study http://www.etl.noaa.gov/programs/1995/sos/banta9801.html)
When inhaled, ozone can damage the lungs (see “Ozone and Your Health”: http://www.epa.gov/airnow/brochure.html). Relatively low amounts can cause chest pain, coughing, shortness of breath, and, throat irritation. Ozone may also worsen chronic respiratory diseases such as asthma and compromise the ability of the body to fight respiratory infections.
People vary widely in their susceptibility to ozone. It is misleading to say that VOCs and carbon monoxide (CO) alone are exacerbating asthma. Any lung irritant can be bad for asthma, but it has been clearly shown that ground-level ozone is very damaging to the lungs and increases asthma hospitalization rates (For a New York City example study, see http://www.cdc.gov/nceh/tracking/wkshop04/pdfs/posters/nyc_2.pdf).
As for toxicology, the damaging effects from exposure to any compound really depends on the amount of exposure. For this reason, EPA developed the Air Quality Index (AQI) to help the public understand the health risk depending on the amount of ozone or smog on a given day (see http://airnow.gov/index.cfm?action=static.ozone2#6). For any AQI level of moderate or higher, I would not say that ozone is a mere irritant nor does the public health literature support that claim.
As for how ozone is used in disinfecting water, that is a separate topic with different exposure concerns. Treating water with ozone requires an ozone generator in a very contained system. See EPA’s fact sheet at http://www.epa.gov/owm/mtb/ozon.pdf, which notes that: “Ozone is extremely irritating and possibly toxic, so off-gases from the contactor must be destroyed to prevent worker exposure. Post-treatment, ozone has limited solubility and decomposes more rapidly in water than in air.”
It is misleading to compare a swimmer’s exposure to residual ozone in the water as tantamount to airborne exposure to ground-level ozone.
Steve Hengsperger
You should also clarify what levels of ozone you are speaking of in these cases. There is always ozone in the air, probably in the neighborhood of 15ppb in the room you are in right now, if there is a window. Photocopiers emit a lot more ozone than this and yet nobody has respiratory problems when near these machines. The amount of ozone that a swimmer would come into contact with is even lower than these levels and when ozone is saturated into water it is perfectly safe and effective, it is currently one of the only FDA and USDA approved processes for sanitizing produce.
MRE
SICK BECAUSE OF OFFICE MACHINES
I have suffered a devastating respiratory condition due to the cocktail of dozens of irritant vapours released by a PHOTOCOPIER AND A LASER PRINTER in my job. It was diagnosed as bronchial hyperreactivity and multiple chemical sensitivity. This has not been officially acknowledged as of occupational origin although there are more cases around the world often misdiagnosed as psychosomatic or anything.
Anyone reading this message is requested to spread the word because there are influential interests preventing the open release of information concerning persons actually going ill because of these office machines. If anyone knows of other cases of persons suffering obscure symptoms and syndromes never well understood who might have been breathing the concentrated vapours of these machines you are also requested to please leave message here for further comments and follow up.
Supreet
The blog has been quite remarable, as it discusses howasthma is caused due to the exhaust produced by the vehicles, and that it gets accelerated when someone gets closer to the vehicle or engine producing it.