Does Air Pollution Cause Dementia ?

[LiberalArkie]

"WE SHOULD GET out of here," says air pollution chemist Eben Cross. At 7 a.m. on this cold November day the wind blows steadily through the Massachusetts Institute of Technology's Cambridge campus, cutting through our thin jackets. But Cross isn't afraid of the cold. He worries about the air we're breathing—especially considering the six fire trucks directly ahead, idling in the dim morning light.

"We're getting hammered right now," Cross says, shouting over the hum of the engines. He's taken his gloves off to manipulate the display panel on his pollution monitor. The acrid smell of diesel is unmistakable. "Anytime you can smell it, you are in a regime that is very polluted," he says. "In many ways your nose is a better mass spectrometer than any device on the market."

Cross' monitor measures the presence of microscopic particles suspended in the air. Earlier, in his home, the device reported average concentrations of between 10,000 and 100,000 airborne particles per cubic centimeter of air (the latter after he burned some toast). Now it detects millions. The massive size of the fire trucks' engines, combined with their inefficient combustion in cold weather, means that the air reaching us is replete with fine and ultrafine particles—specks of waste at least 36 times finer than a grain of sand, often riddled with toxic combinations of sulfate, nitrate and ammonium ions, hydrocarbons, and heavy metals. Though we have long known that these tiny particles cause and exacerbate respiratory problems—like asthma and infections and cancers of the lungs—they are also suspected to contribute to a diverse range of disorders, from heart disease to obesity. And now cutting-edge research suggests that these particles play a role in some of humanity's most terrifying and mysterious illnesses: degenerative brain diseases.

While coarse pollution particles seldom make it past our upper lungs, fine and ultrafine particles can travel from our nostrils along neural pathways directly into our brains. Once there, they can wreak a special havoc that appears to kick off or accelerate the downward spiral of degenerative diseases like Alzheimer's and Parkinson's. While much of the research is still preliminary, the findings so far are compelling. Autopsies of the brains of people who lived in highly contaminated areas have turned up traces of pollution and corresponding brain trauma. And among those still living, epidemiologists have recorded elevated rates of brain disease and accelerated mental decline.

Snip

http://www.motherjones.com/environment/2015/05/air-pollution-dementia-alzheimers-brain

[KamaAina]

1. Easy hypothesis to test

If L.A. and Houston have higher rates of dementia than the rest of the country, and Beijing and Mexico City than the rest of the world, then the answer is probably Yes.

[The Straight Story]

2. I can't recall. (nt)