[silisili]

I did a -lot- of research on a house about 1500 feet of a freeway.

It seemed to me nearly all of it was correlative. Which is fine, as it may be true.

But very few corrected for the fact freeways often run through the worst areas in town, which could mean nutrition, drugs, alcohol, lead paint, asbestos, heck about anything else bad about living in older, run down areas.

[taeric]

Your point relies on the causative link not being that having a freeway through a section causes it to decline into being the worst part of town.

[silisili]

Well, there's plenty of rural and 'rich suburban' areas close to freeways. In my county in Florida, they're building brand new 500k dollar houses 100 feet from the freeway. For reference, 500k is high end of house prices here.

Would be interested to see if those show the same.

If not, you could rule out white noise completely. That would then seem to point to other factors, including total pollution, or more socioeconomic things.

[taeric]

Apologies, I should have left my point more open. That is, I don't know that there is a link. Would love to see evidence.