Combating the Pollen Count

With global warming pushing up average temperatures, allergy and asthma suffers can expect increased exposure to pollen and ragweed. This much is evident in reports from the Center for Health and Global Environment at Harvard Medical School, whose 2005 Climate Change Futures (CCF) studies examined the effects of global warming on health and environment including pollen levels. These studies show a correlation with increased ragweed pollen, due to rising carbon dioxide (CO2) levels, as well as increased incidents of asthma. Tree pollen levels are rising as well: a Duke University study showed that when CO2 levels doubled Loblolly pines tripled their seed and cone production, making more pollen in the process.

City dwellers are not exempt from increased pollen and ragweed, as CCF point out, targeting urban "heat islands" with increased heat and higher CO2 levels from car exhaust, and abandoned city lots given-over to ragweed as problem zones. As temperatures rise, and CO2 levels with them, flowering plants are expanding their range of growth northward, producing pollen earlier and longer. Plants are even making pollen more efficiently since increased CO2 also increases photosynthesis and reproductive effort. This may sound like good news if you are a ragweed, but for asthma and allergy suffers, the results are devastating. With allergy treatments costing the U.S. health care system $18 billion annually, there is reason for concern on a national scale.

However, cleaning can reduce our exposure to airborne allergens. Regular vacuuming helps to remove dust and pollen from interior surface, and some vacuums outfitted with High Efficiency Particulate Air (HEPA) filters reduce the amount of particulate matter on floors and carpets as well as in the air (see below). Harvard's Climate Change Futures report suggests that individual measures to reduce exposure to indoor and outdoor allergens is the first step toward reducing asthma symptoms and complications.

Air filtering or purification systems are also tools in the fight to decrease particulate matter in indoor air. Some, however, are better than others, and some should be avoided completely. While the jury is still out on precisely how effective air purifiers actually are at purifying—according to 2005 studies from Consumer Reports the majority of air purifiers were ranked as fair or poor—the American Academy of Allergy, Asthma and Immunology maintains that purifiers can help decrease air quality problems such as dust, pollen and mold spores, especially when used in conjunction with good cleaning and home maintenance. The key is finding the correct, and most efficient model of purifier for your situation.