80% of Urban Areas Have Unhealthy Amounts of Air Pollution - Here's How You Can Limit Your Exposure

Regardless of individual efforts, pollution is all around us. For some, this fact leads to a certain defeatist attitude when it comes to making more of an effort to protect the environment. But what about making more of an effort to protect your health?

Research published last year shows that over 5.5 million people die prematurely each year due to air pollution around the world. Compiled by the Global Burden of Disease project, this statistic reflects a growing trend found in particular in the developing economies of China and India. The problem has become so bad that the World Health Organization now estimates air pollution is a greater threat to global health than the Ebola virus or HIV, with 80% of urban areas experiencing air pollution levels above what’s considered healthy.

As for the cause for this concern? The project’s researchers primarily point to the emission of small particles from power plants, factories, vehicle exhausts and the burning of coal and wood. Dan Greenbaum, who works for the Health Effects Institute in Boston, explained to the BBC that on a “bad air pollution day” in Beijing or Delhi, “the number of fine particles (known as PM2.5) can be higher than 300 micrograms per cubic meter.” Putting that in context, Greenbaum continued, “the number should be about 25 or 35 micrograms."

Before we get to the ways we can reduce our exposure to particulate matter, we first need to know exactly what PM is. PM, according to the California Environmental Protection Agency, is “a complex mixture of small solid particles and liquid droplets found in the air." Allergens such as pollen, mold spores, dust mites and cockroaches can also cause PM. In China alone, the hazardous health effects of exposure to PM account for up to 360,000 deaths a year, according to the project, from causes like heart disease to respiratory problems and cancer.

Like most types of pollution, this is a problem best addressed through government policy. As Michael Brauer, a researcher from the University of British Columbia, explained to the BBC: "In the U.S., we know that for every dollar spent on air pollution improvements, we can get between a $4-$30 benefit in terms of reduced health impacts."

Waiting for government intervention, though, could take a while. Ultimately, the responsibility falls on each of us to make the necessary changes needed to combat the adverse effects of air pollution on our health. To help with this, below are some simple ways to help reduce exposure to airborne pollution.

In vehicles

The California Environmental Protection Agency describes the “combustion of gasoline and diesel fuel in motor vehicles” as the main contributor to PM in urban Californian environments. The agency suggests the following steps for reducing exposure to PM in vehicles:

• Try spending less time driving during rush hour.
• If you are sitting in traffic, close your vehicle’s windows and use the air recirculation/close vents setting. (Make sure to air out the vehicle on occasion to avoid a buildup of exhaled carbon dioxide.)
• If possible, install a high efficiency particle filter in your vehicle.
• Avoid portable electronic air cleaners as some of them produce ozone, another form of PM.
• Avoid leaving your vehicle idling in an enclosed space such as a garage.
• Don’t smoke in the car, especially when the windows are closed (although seriously, if you're a smoker, opening the windows may not make too much difference).
• Consider an electric hybrid (gasoline-electric) or other low-emitting vehicle when it comes time to buy your next car.

Prashant Kumar from the University of Surrey explained to Sciencedirect that drivers stopped at traffic lights were exposed to PM 29 times more harmful than those in moving traffic. Kumar offers the following advice: "Where possible and with weather conditions allowing, one of the best ways to limit your exposure is by keeping windows shut, fans turned off and to try and increase the distance between you and the car in front while in traffic jams or stationary at traffic lights."

On the streets

A 2009 University of Leeds study suggested several ways pedestrians could reduce their exposure to PM. As reported in Science Daily, the study offered the following simple suggestions.

• Bikers or pedestrians should stay a street or two away from main intersections to avoid air pollution concentrations.
• Avoid parallel side streets. Carbon monoxide is four times higher on parallel side street than on main streets, which is due to a lack of adequate air flow that leads to a buildup of pollution.
• According to University of Leeds professor Alison Tomlin, PM tends to accumulate on “the leeward side of the street, (the sheltered side) in relation to the wind's direction at rooftop level." So stick to the side with shorter buildings.

In your home

The greatest exposure to PM indoors happens during cooking, according to the California EPA. The agency suggests taking the following measures to improve air quality in your home:

• When cooking, use exhaust fans that vent to the outdoors. If you don’t have a vent, get yourself a high-efficiency portable air cleaner.
• Electric or gas stoves and heaters are better than those powered by wood. But if you have a wood fire in your home during winter, make sure the wood is dry and that the drafts in your fireplace or woodstove work efficiently.
• Get your gas heaters and stoves checked annually by a professional.
• Never use hibachis, charcoal grills or unvented space heaters indoors.
• When burning candles or incense indoors, make sure they are placed near outside air ventilation.
• Avoid smoking indoors at all costs. PM from cigarette smoke sticks to fabrics and carpeting and creates a significant health hazard.
• Use only natural cleaning supplies, as artificial products often react with ozone to form PM.
• When generating any form of moisture indoors—showering, cooking or dishwashing—make sure there’s ventilation to avoid the growth of molds and dust mites.
• Get yourself a smart sensor, a mechanism that monitors air quality and alerts you to dangerous levels of carbon monoxide and other potential PM. Two such devices currently on the market are CleanSpace Tag and Birdi.