Findings from a new study on air pollution found that notwithstanding lower traffic volumes, "heavily traveled secondary highways" may be just as toxic as freeways laden with diesel trucks or major railyards.
Students at a Roseville middle school near busy, 6-lane Watt Avenue "are breathing higher levels of toxic particles than people immediately downwind of the Roseville train yard, the single largest generator of such pollution in the Sacramento area, according to an air pollution study scheduled to be released today (Dec.13).
"It shocked us all," said Thomas Cahill, a University of California, Davis, atmospheric physicist who led the study."
"Those findings spurred Cahill to look deeper. How could particle pollution that is normally associated with diesel soot be just as high along residential Watt as a freeway, with all its soot spewing trucks and buses? The most likely answer, the scientists concluded, was that the particles near the Arden school came mostly from run-down cars burning engine oil.
"A small fraction of cars dominates the automotive pollution," Cahill said. "That's a small fraction of cars putting out very toxic stuff."
Smoke from burned motor oil contains benzo-a-pyrene, the most prevalent cancer-causing air pollutant in California, Cahill said.
"Just because people may live along residential streets instead of freeways doesn't mean that they're safe from the harmful effects of car exhaust particulates, " Cahill said.
Thanks to Jennifer Finton

Maui's Vacation Rental Debate Turns Ugly
Verbal attacks, misinformation campaigns and fistfights plague a high-stakes debate to convert thousands of vacation rentals into long-term housing.

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

In Urban Planning, AI Prompting Could be the New Design Thinking
Creativity has long been key to great urban design. What if we see AI as our new creative partner?

King County Supportive Housing Program Offers Hope for Unhoused Residents
The county is taking a ‘Housing First’ approach that prioritizes getting people into housing, then offering wraparound supportive services.

Researchers Use AI to Get Clearer Picture of US Housing
Analysts are using artificial intelligence to supercharge their research by allowing them to comb through data faster. Though these AI tools can be error prone, they save time and housing researchers are optimistic about the future.

Making Shared Micromobility More Inclusive
Cities and shared mobility system operators can do more to include people with disabilities in planning and operations, per a new report.
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.
planning NEXT
Appalachian Highlands Housing Partners
Mpact (founded as Rail~Volution)
City of Camden Redevelopment Agency
City of Astoria
City of Portland
City of Laramie