There is an article in the LA Weekly this week about living near highways. It mainly argues that the LA City Council has ignored evidence of the health risks of living near highways and allowed developers to build highway-adjacent developments.
Here are the facts I pulled from the article:
- Residents living near highways note that a lot of “dust” builds up in the apartment.
- USC scientists have done two studies. The first was called the “Children’s Health Study,” published in the New England Journal of Medicine. This studied 1,700 children and compared children who live in relatively clean-air zones to children who live in more polluted areas. High rates of underdeveloped lungs were seen in the polluted areas.
- The second study was a longitudinal study of 3,600 children. Children living within 528 feet of a freeway suffer reduced lung development.
- Another study involving USC researchers reported that hardening of the arteries is twice as common among Angelenos living within a block of an LA freeway.
- A study from UCLA reported that pregnant women within 750 feet of a freeway have a greater-than-average risk of delivering premature babies.
- McConnell, a USC environmental health researcher, has said that the smallest particles pass through the respiratory system, into the body and the brain.
- He also says that pollution tests have shown that traffic-related pollutants diminish rapidly within about 300m (984 feet) from the freeway.
- Home air-filtration systems will not remove the smallest particles from the air.
I was very disappointed to see that the article did not actually quantify most of these facts. For #2, #3, and #5, the magnitude of increased risk was not given. For #6, the relevant question to ask is what is known about the health implications of the particles. For #8, what risk do the smallest particles cause, what concentrations are they present in, and what should we compare these numbers to?
I can easily believe that living near a highway is probably worse than not living near a highway, all other things being equal. I have noticed that dirt/dust/stuff builds up on my outdoor furniture at a much greater rate than other places I have lived. I think we need more scientific studies of this type to assess health risks, and I agree with the main point of the LA Weekly article that city government needs to pay attention to scientific studies to set zoning policies.
But… but… printing an article without any numbers in it just gets people scared, without giving them the information they need to actually assess risk. For example, driving on the freeway each day also increases the amount of time you spend breathing particulate-laden air. So is it better to live within 1000 feet of a freeway but not commute, or live 0.5 miles from a freeway but spend 1.5 hours each day on the freeway in your car? Any sensible analysis of overall risk has to take into account your total exposure levels throughout the day.