Smarter Living: Family Health
The Diesel on the Bus
Photo: Larry Darling
If your child is one of the 23 million kids who ride the bus to school every day, be advised: Her bus probably has a diesel engine and the exhaust from that engine contains invisible but harmful pollutants that are getting inside.
Nine out of ten of the nation's 454,000 school buses burn diesel fuel. School districts typically prefer diesel engines because they're durable, heavy-duty haulers. They're so durable that a third of today's school bus fleet is 18 years or older.
The problem however is that diesel engines emit ultrafine particles that can provoke asthma attacks and increase the risk of cancer. Research conducted by the non-profit Environment and Human Health, Inc, and more recently by NRDC, show that diesel exhaust gets inside the bus. In fact, the NRDC tests showed air quality is eight times worse inside the bus than regular outdoor air.
"It's not the black soot you can see. These ultrafine particles are so tiny," says Diane Bailey, NRDC scientist in the Health and Environment Program, "they can slip by the body's regular filters and travel deep into the lungs." From there they can enter the blood stream which is how they can cause the most damage, triggering heart attacks, asthma attacks, allergies, and bronchitis.
Cancer is another risk. Diesel exhaust is a toxic soup and mercury, chromium, benzene and other well known toxins hitchhike on the tiny particles, getting a ride deep into the lungs and blood stream. Some cause cancer, especially lung cancer. The State of California says diesel causes 70 percent of all airborne cancer risk. Others are neurotoxins which attack the brain, spinal cord and nerves. Diesel exhaust also creates smog, boosting local ozone levels (bad news for kids with asthma), and adding to acid rain and global warming.
What You Can Do
- If your child must ride the bus, encourage him to sit in the front, with the windows open.
- If walking or biking is an option, that is the healthiest choice. Petition your town to install sidewalks, crosswalks and bike lanes.
- Work with your school to set up an anti-idling policy to stop school buses from running their engines in front of school buildings. Several school districts, towns and cities around the country, such as the city of Nashua, NH, have put in successful anti-idling laws. Read "Smarten Up and Stop Idling" to learn more. If cold weather is an issue, ask school officials to designate a waiting area inside the school building for drivers to warm-up.
- Take a look at your school's parking lot. Buses should be parked away from air intake vents in the school to prevent exhaust from entering the building. A chain of bumper to bumper buses builds up exhaust and contaminates each bus in line, so buses should park diagonally, if possible.
- Make sure your school district has a quality maintenance program for its bus fleet. Exhaust problems are worse in buses with poor maintenance. Retrofit older buses with pollution control traps on the tailpipe. These controls come automatically now with newer buses.
- Encourage your school district to replace older buses with buses that run on alternative fuels. Propane, natural gas and hybrid electric buses are the best long-term solution. Target pre-1990 buses, since emissions standards tightened up in 1991. Older buses also lack basic safety standards. New buses are expensive, often $250,000 each. Write grants to help your local school district find money to retrofit and replace buses. Best place to start: Clean School Bus USA, a federal program run by EPA. Contact them to learn about new federal funding sources and link up with local and state funding in your area.
- Talk to school and bus company officials about rearranging routes for the bus fleet. Move the cleanest, newest buses to the longest routes and save the oldest buses for the shortest routes. Since impacts from diesel exhaust are cumulative, this interim step minimizes exposure to all kids.
With a few simple steps, you can help to make your kids' school days healthier.
last revised 1/5/2012