Houston must fight diesel exhaust

This piece originally appeared as an op-ed in the Houston Chronicle

As Houston looks toward a major local election later this year, one issue is looming large: traffic. Houstonians are spending more and more time in their cars, and the problem is only getting worse. By 2040, the number of vehicles on our roads will increase by 60 percent and the amount of freight will double. All this traffic isn’t just an annoyance – it is hazardous to our health.

Sitting in traffic is one of the main routes of exposure to diesel exhaust, a ubiquitous air pollutant with many negative health impacts. The International Agency for Research on Cancer recently classified diesel exhaust as a Group 1 human carcinogen, putting it on par with arsenic, asbestos and benzene.

Air Alliance Houston has found elevated cancer risk due to diesel pollution exposure in the Houston-area community of Galena Park. One of the main boulevards through Galena Park, Clinton Drive, is a major conduit for diesel truck traffic to the Houston Ship Channel. Our research suggests that increased cancer risk due to diesel exhaust exposure may exceed one case in 10,000 in many areas of Galena Park. This is far in excess of the generally accepted cancer risk limit of 1 in 1 million.

Diesel exhaust also harms babies’ brains. Diesel exhaust is filled with compounds knows as polycyclic aromatic hydrocarbons (PAHs), which may impair brain development both before and just after birth. A recent study published in JAMA Psychiatry found that prenatal exposure to PAHs may impair development of white matter in the brain’s left hemisphere, leading to learning disabilities and behavioral problems. After babies are born, further exposure to PAHs my impair white matter development in other brain regions.

Research in Houston has shown that 80,000 children are already at risk due to the proximity of their schools to high traffic roadways. Exposing our children to any more traffic pollution than necessary is an unacceptable risk.

One way to reduce traffic pollution is to limit idling from heavy-duty vehicles such as trucks and buses. The EPA estimates that one truck can burn 1,830 gallons of fuel a year while sitting idle. Eliminating that idling could save the driver $4,750 each year and cut 21 tons of carbon dioxide emissions.

You don’t have to live in Galena Park to see examples of heavy-vehicle idling. Visit Hermann Park during the school year and you are likely to see dozens of school buses idling outside our parks and museums. Children on field trips often crowd around these buses, milling about at tailpipe level.

Many of the steps that we can take to limit the impact of diesel exhaust on our health will also improve traffic in Houston. One way to cut exposure to diesel pollution is to avoid getting stuck in traffic in the first place. Take advantage of flexible working hours to commute at off-peak times or telecommute. Set up carpools or “walking buses” to get your kids away from school bus traffic.

The city of Houston can take action, too. Transportation infrastructure plans should include dedicated truck lanes to get diesel vehicles away from the public and eliminate traffic jams caused by truck collisions. Dedicated infrastructure for freight vehicles can also provide alternatives to idling. More sophisticated entry gates and priority lines for clean vehicles can reduce wait times. Truck stops with access to plug-in electricity can eliminate the practice of “hoteling,” when truck drivers spend the night in their vehicles with their air-conditioning – and their engines – running.

Right now, the best thing Houston can do to reduce diesel pollution is pass a city ordinance limiting heavy-vehicle idling. Texas gives cities express authority to do this. Both Dallas and Austin have adopted ordinances that limit idling to five minutes at a time.

Air Alliance Houston is asking Houston’s City Council to adopt an idling ordinance as well. If you agree, then you can help. Call your city councilmember and tell them you want limits on heavy-vehicle idling in Houston. You also can call 311 to report air pollution when you see vehicles idling for long periods of time, such as queues of buses or de facto truck stops in empty parking lots. If the public demands it, our elected officials will respond.

Working together, the city of Houston and its people can improve traffic, limit vehicle idling and protect our health.

You can support Air Alliance Houston in its campaign for an idling ordinance by signing our petition!