How Far Away is Far Enough?

Evidently, I haven't written a blog post since November, which is not-coincidentally when my sons and I made the decision to sell or rent out our respective houses and find a shared-but-separate home together. Since that time, I've been fairly consumed with the logistics involved in making a move. I've written about housing enough in the past that I don't think I need to rehash all the difficulties involved for people with chemical illness. It's a huge issue, and I would truly appreciate prayers for the process.

One of the initial challenges my sons and I are encountering in the house hunting journey is the difficulty of finding a home far enough away from highways and other busy roads. Unfortunately, it's difficult to say with precision how far away is far enough, even for people without chemical illness. Traffic pollution is a significant health issue, both because it's so hard to avoid and because it contains a complex mixture of both gaseous pollutants and fine particulate matter. Here's some of the information I've found:

• A publication by the National Resources Defense Council notes that health effects related to traffic pollution include cancer, heart disease, asthma, decreased lung function, pre-term birth, birth defects, and increased mortality related to such factors as heart attack, stroke, and  pneumonia.

• The publication notes that dramatically elevated pollutant levels are generally found within 500 feet of busy roadways, but under certain conditions can extend much further.

• An article in the Digital Journal notes that people living within 300 feet of major roadways have higher rates of respiratory conditions, allergies, heart disease, and certain types of cancers.

• The author reports that a California study found that in the early morning hours, traffic pollution travels a mile or more from the highways.

• The article also states that the American Lung Association's 2013 "State of the Air" report determined that living or working within 0.3 miles of a highway or road is "more dangerous than people have been led to believe."

• A Time magazine article reported on a study finding that children whose families lived within 1,000 feet of a freeway when they were born were twice as likely as others to have autism.

• The Southern California Particle Center and Supersite (SCPCS) notes that many factors influence exposure to traffic pollution. These include weather conditions, such as temperature, humidity, and the speed and direction of the wind. Whether a home is upwind or downwind of the roadway is important, as is the construction of the house and the type of filtration system it has. Whether people are outdoors during peak traffic times or indoors with open windows also affects exposure levels.

So how close is too close? The SCPCS concludes that "scientists cannot say exactly how close is 'too close' at this point" and that "the closer people are to the source of traffic emissions, the higher their exposure is to many of the constituents of exhaust."  Studies indicate that vulnerable populations, such as children, the elderly, or those with pre-existing health conditions should be especially careful. An article in the American Journal of Respiratory and Critical Care Medicine notes that exposure to traffic-related pollution can contribute to the development of COPD and that enhanced susceptibility is seen in people with asthma, which might be expected, and diabetes, which seems to me a less obvious association. Although I haven't seen this advice in print, I've been told that one expert in toxic illness recommends that those of us who suffer from MCS live at least five miles from a highway, which seems like good advice that can be extremely difficult to follow, especially when taking the needs of other family members into account.

Mitigating the health effects of traffic pollution, especially for those not planning a move, isn't easy. Avoiding as many other sources of chemical exposures as possible will help lower the overall toxic burden on the body. Good air filtration can help, as well, and planting vegetation can also be of some use. Although, in general, indoor air pollution is higher than that found outdoors, those living near busy roadways may find it prudent to shut windows and stay indoors during peak traffic hours.

To a degree, the issue seems to be gaining more attention. As I noted in a previous post, some state and local authorities are beginning to address the issue of building schools near major roadways, while others continue to ignore the risks. Compelling evidence of health effects does not appear to be enough, in and of itself, to consistently motivate action. Perhaps a growing awareness of the issue will inspire parents to raise the issue and apply pressure when decisions are being made.

Will the pollution from busy roadways become less problematic as electric and hybrid cars increase in popularity? Yes, to a degree, but some experts conclude that fine particulates from tire wear and roadway dust may continue to be an issue. I'm personally not pinning my hopes on a quick decrease in levels of exhaust fumes and am going to continue to pass on homes that are too close to busy roadways, no matter how well they fit other criteria. I just wish it weren't quite so challenging to figure out how far away is far enough.