2012 May 07 Monday
Higher Heart Risk When Living Near Highways

Beware the demon car exhaust. Long range commuters probably face a similar risk.

BOSTON – Living close to a major highway poses a significant risk to heart attack survivors, reinforcing the need to isolate housing developments from heavy traffic areas, a Beth Israel Deaconess Medical Center study concludes.

Writing in the May 7 edition of Circulation, researchers found heart attack survivors living less than 100 meters or 328 feet from a roadway have a 27 percent higher risk of over within 10 years than survivors living at least 1,000 meters away. That risk recedes to 13 percent for those living between 200 and 1,000-meter or 656 to 3,277-feet from the roadway.

"Living close to a highway is associated with adverse cardiovascular outcomes in those with underlying cardiac disease," says Murray Mittleman, MD, DrPH, a physician in the CardioVascular Institute at Beth Israel Deaconess Medical Center, an Associate Professor of Medicine at Harvard Medical School and director of BIDMC's cardiovascular epidemiological research program. "Besides air pollution, exposure to noise could be a possible mechanism underlying this association."

I have a HEPA air filter unit running as I type this. I wonder how much it reduces health risk from living near a moderately busy nearby roadway.

Also see a previous post on why green acres is the place to be.

By Randall Parker    2012 May 07 10:24 PM   Entry Permalink | Comments (13)
2012 April 29 Sunday
More Coronary Artery Calcification With City Living

"Green acres is the place for me. Farm livin' is the life for me."

City centre residents who took part in a study were almost twice as likely to suffer from coronary artery calcification (CAC), which can lead to heart disease, than people who lived in less polluted urban and rural areas, according to research published in the May issue of the Journal of Internal Medicine.

Researchers spoke to 1,225 men and women aged 50 and 60 years of age, including 251 (20%) who lived in the centres of major Danish cities.

Despite the fact that none of the participants showed any symptoms of heart disease, 43% of the total had CAC. The study also found that people who lived in city centres were 80% more likely to develop CAC than those living in other areas and that males, older participants, diabetics and smokers also faced higher risks.

I hear singing:

Low blood vitamin D is associated with more coronary artery calcification (CAC). Also, garlic may retard the progression of CAC.

If you must live in the city: Consider a HEPA filter. Also, try to live on a higher floor away from vehicle exhaust soot.

By Randall Parker    2012 April 29 12:47 PM   Entry Permalink | Comments (6)
2011 April 14 Thursday
Chronic Air Pollution Causes Inflammation

White blood cells reacting to chronic air pollutants will stoke up changes that cause cardiovascular disease and other diseases.

COLUMBUS, Ohio – Chronic inhalation of polluted air appears to activate a protein that triggers the release of white blood cells, setting off events that lead to widespread inflammation, according to new research in an animal model.

This finding narrows the gap in researchers’ understanding of how prolonged exposure to pollution can increase the risk for cardiovascular problems and other diseases.

When you are thinking about where to live or work consider air quality. Too many office buildings get built near freeways because people are averse to living near freeways. Well, unless you get an employer who will shell out the bucks for a thorough air filtration system a job next to a freeway could set you up for cardiovascular problems and other diseases that can be accelerated by inflammation.

Here is what I'd like to know: Suppose you are going to live next to a freeway or near other major air pollution sources. How much of the bad stuff in the air can get scrubbed out by the right air filtration system? In particular, is a basic HEPA filter good enough against vehicle air pollution? Most discussions of air filtration seem to center around allergens because so many people know they are allergen sensitive. It is relatively harder to find informed discussions about pollutant filtration. So I'm left wondering at the utility of more powerful filtration systems that work against chemicals in the air. Know pertinent facts about pollutants and air filtration? Can air filtration systems make living next to a freeway safe?

Update: So how close to a highway is close enough to worry? The first 100 meters (about 300 feet) are the worst and by 300 meters distance there's little effect from a highway on air quality. These are approximate numbers due to different geographies and traffic loads and wind patterns. Check out a graph of particle concentration as a function of distance from a highway in LA as an example.

Unfortunately, the smallest particles are both harder to filter and quite harmful (and read that article if you want to rationally fear air pollution). I am still left wondering how well air filtration systems can work for those who dwell near major highways. My guess is they will substantially reduce harm from vehicle pollution. But can they totally eliminate the added health risk?

By Randall Parker    2011 April 14 11:11 PM   Entry Permalink | Comments (9)
2010 May 23 Sunday
Pollutants Risk Factors For Type 2 Diabetes

Two pollutants and two nutrients influence the risk of getting insulin resistant type 2 diabetes.

By comparing the blood or urine concentrations of each factor between the case group and the control group, Butte and Patel identified four factors linked to the disorder. Their analysis confirmed previous findings that high blood levels of industrial pollutants called polychlorinated biphenyls (PCBs) were highly associated with the disease. The prevalence of Type 2 diabetes was two to three times higher for those with the higher levels of the pollutant compared to those with the lowest. Type 2 diabetes prevalence among those with high levels of heptachlor epoxide, a break down product of a previously common pesticide, was at about two times higher than those with low levels of the compound. (The United States banned the manufacture of PCBs in the United States in 1979 and banned heptachlor for most uses in 1988, but the compounds persist in the environment, especially near former industrial sites or contaminated soil.)

Type 2 diabetes typically develops in late middle age. Obesity, lack of exercise, high cholesterol, and high triglycerides are among the risk factors for it. Type 2 diabetes increases the risk of many diseases including heart disease, stroke, kidney failure, blindness, and 24 types of cancer.

Surprisingly, consumption of the gamma tocopherol form of vitamin E is positively associated with type 2 diabetes risk.

The analysis also indentified a factor never before linked to type 2 diabetes: a form of vitamin E called gamma-tocopherol. Vitamin E appears in eight different molecular forms; gamma-tocopherol is the most common form in the American diet. Prevalence of type 2 diabetes among study participants with high blood levels of gamma-tocopherol—which, like other forms of vitamin E, is an antioxidant—was two times greater compared to people with low levels of the nutrient. Butte says that much additional research is needed to sort out how this form of vitamin E is related to type 2 diabetes. “This finding, in particular, shows the value of surveying across as broad a range of environmental factors as possible,” Butte says.

On the bright side, carrots and other sources of beta carotene probably will cut your risks of type 2 diabetes by 40%.

There was also good news. Butte and his colleagues confirmed previous studies showing the protective association of the vitamin beta-carotene. The prevalence of type 2 diabetes among people with high amounts of beta-carotene, a form of vitamin A, was about 40% lower than those with lowest amounts of the vitamin.

By Randall Parker    2010 May 23 10:16 PM   Entry Permalink | Comments (0)
2009 March 12 Thursday
Higher Ozone Levels Increase Death From Respiratory Diseases

Pollution kills. That's why I want solar, wind, nukes, and geothermal to replace coal and natural gas for electricity generation.

NEW YORK, March 11, 2009 – Long-term exposure to elevated levels of ground ozone—a major constituent of smog—significantly raises the risk of dying from lung disease, according to a new nationwide study of cities that evaluated the impact of ozone on respiratory health over an 18-year period.

The study found that the risk of dying from respiratory disease is more than 30 percent greater in metropolitan areas with the highest ozone concentrations than in those with the lowest ozone concentrations.

Over the last decade, several nationwide studies have shown that long-term exposure to tiny particles of dust and soot in air pollution is a risk factor for death from heart and lung disease. However, it was unclear whether long-term exposure to ozone, a widespread pollutant in summertime haze, was linked to a higher risk of dying from lung disease itself.

The new study, published in the March 12 issue of the New England Journal of Medicine, is the first nationwide population study on the long-term impact of ozone on human health, and the first to separate ozone's effects from those of fine particulate matter, the tiny particles of pollutants emitted by factories, cars, and power plants.

Stay out of Riverside and Hell-A California. Why do people live in these places? It is a puzzle.

Ozone data collected between 1977 and 2000 showed that California had both the city with the highest and the city with the lowest concentration of ozone pollution in the country. The researchers estimate that the risk of dying from respiratory causes rises 4 percent for every 10 parts-per-billion increase in exposure to ozone. Based on that result, Dr. Thurston says the city with the highest mean daily maximum ozone concentration over the 18-year period of the study, was Riverside (104 ppb). This long-term cumulative exposure corresponded to roughly a 50 percent increased risk of dying from lung disease compared to no exposure to the pollutant. Los Angeles ran a close second, with an estimated 43 percent increased risk.

Northeast cities were generally lower in ozone than California. In Washington, DC, and New York City, for example, the study results indicate a 27 and 25 percent increased risk of respiratory death, as a result of their respective long-term ozone exposures, says Dr. Thurston. The estimated increased risk from cumulative exposure in New York occurs even though New Yorkers breathe air that is nearly in compliance with the EPA's present short-term ozone standard of 75 ppb, he says.

San Francisco's fog protects.

The lowest ozone concentration was seen in San Francisco (33 ppb long-term average daily maximum), which had an associated 14 percent increase in risk. San Francisco has low levels of ozone pollution because fog regularly blankets the city, which prevents the necessary photochemical reaction from occurring, says Dr. Jerrett. In addition, Dr. Thurston points out that the Los Angeles area, which has high levels, is located in a basin, which prevents the rapid dispersal and dilution of air pollution that occurs in San Francisco.

If you are living in the United States then you can check out your own county's ozone levels as measured by the EPA (PDF document).

By Randall Parker    2009 March 12 11:53 PM   Entry Permalink | Comments (1)
Site Traffic Info