Study reveals longer season in some parts of the nation
A recent study, led by the United States Department of Agriculture (USDA), in collaboration with Rutgers, has confirmed a link between seasonal warming and a longer ragweed season in some parts of central North America.
Leonard Bielory, M.D., a specialist in allergy and immunology with the Department of Environmental Sciences at the School of Environmental and Biological Sciences participated in the USDA study as part of his federal research funding to examine the impact of "Climate Change on Allergic Airway Disease."
The impact of the USDA study for allergy sufferers in New Jersey is that there are changes in the onset and length of the ragweed allergy season.
"Climate change appears to be associated with early pollen seasons that last longer causing more people to suffer from pollen induced allergies," said Bielory.
This will affect those with tree allergies, which started during the month of February this year and will especially hit hard those suffering from "hay fever" that occurs at the end of August and goes through the first frost. Allergy to ragweed – neither an allergy to hay nor a fever – is associated with the release of ragweed pollen while hay is being harvested. "The fever only comes about when patients develop secondary sinus problems like allergic sinusitis," he added.
Lewis Ziska, a plant physiologist with the Agricultural Research Service of the USDA, led the multi-institution study team that examined at least 15 years of data on local ragweed pollen counts from 1995 to 2009 for 10 locations along a north-south transect from Austin, Texas, to Saskatoon, Canada. The researchers compared the pollen data at each selected site to other site data, including latitude, the number of frost-free days and delays in the onset of the first fall frost.
The findings, published in February in the Proceedings of the National Aacademy of Sciences, confirms that pollen from ragweed lasts several weeks longer than it did in 1995 and is linked to shifts in climate at the higher latitudes.
According to Bielory, the Intergovernmental Panel on Climate Change projections has suggested that climate change reflects a variety of atmospheric changes "not just global warming in some areas, but cooling in others, and thus will cause early pollination in some areas as demonstrated by the linking of "warming" (increased temperatures) as a function of latitude."
Bielory is principal investigator on a long-term U.S. Environmental Protection Agency grant to study the potential impact of such changes on human population and what to expect over the course of the next 50 years. Preliminary reports, such as the USDA study, suggest that allergies will likely become an increasing problem that "will not only affect our children, but our grandchildren" for the next two to three generations.
"The increased exposure to allergens may also increase the propensity to develop more serious respiratory problems such as asthma and bronchitis," he cautioned. Allergic disorders, including seasonal ragweed sensitivity, contribute to a host of chronic diseases in the U.S., at a public health cost of more than 6 billions of dollars each year.
"Regretfully the changes that we are seeing with weather patterns set the stage for an increasing number of patients with allergies and those with allergies already will note increasing symptoms that may lead to increase hospital and emergency room admissions," added Bielory.
"Patients should seek the advice of their allergist or primary care physician on how to take a more active and preventive role in the care of their allergies and asthma, for the foreseeable future," said Bielory.
Media Contact: Leonard Bielory
973-912-9817
E-mail: bielory@envsci.rutgers.edu