Global Warming Makes You Sneeze; New `Real World' Research Shows Ragweed Likes Warm Air And CO2.

Business Editors/Health/Medical Writers

PLYMOUTH MEETING, Pa.--(BUSINESS WIRE)--Feb. 24, 2003

In the first-ever research of its kind conducted in situ (in the real world, out of doors), scientists at the USDA, Multidata LLC, a division of Surveillance Data Inc. (SDI) and the Macalester College Department of Biology have determined that two characteristics associated with global warming, higher temperatures and increased levels of atmospheric carbon dioxide, contributed to ragweed growing faster, flowering earlier, producing significantly larger plants and generating more pollen in urban areas than in rural areas. For the first time, research has established a relationship between climate change and potential human to pollen.

"This research demonstrated that climate change directly affects human health," said Dennis E. Gebhard, vice president of aerobiology at SDI. "Anywhere the atmospheric carbon dioxide concentrations increases, one can expect a longer, more severe ragweed pollen season."

"Although we did not measure allergy suffering in this particular investigation, many previous studies have demonstrated a strong association between pollen counts and allergy symptoms," Gebhard offered. "Higher ragweed pollen counts clearly translate into more intense allergy symptoms and greater medication use."

"We knew from our previous studies that ragweed plants respond in dramatic ways to increases in both temperature and atmospheric carbon dioxide, two characteristics associated with future global warming," said Dr. Lewis H. Ziska, director of the project at the Alternate Crop and Systems Laboratory, USDA. "But that work was conducted indoors, in a laboratory environment. This latest study was necessary to demonstrate that the observed phenomena also occur in 'real world' settings encountered by the typical allergy sufferer."

Using a transect that included four sites in rural, semi-rural, suburban and urban Maryland, and ragweed seed from a common lot, the research team grew, watered, harvested and monitored the plants beginning in April 2000. Twelve Rotorod(R) Samplers, manufactured by Multidata LLC, were used in an array surrounding the plots to measure and quantify the pollen that actually became airborne.

The research showed that urbanization increased the average daily (24-hour) carbon dioxide by 30 per cent and 31 per cent in 2000 and 2001, respectively. In addition, ragweed seed emerged 3-4 days earlier at the urban site. By maturity, above ground biomass had increased by 8 per cent to 10 per cent at the semi-rural site and 61 per cent to 66 per cent at the suburban site in 2000 and 2001 and by 189 per cent at the urban site in 2001 in comparison to the rural site.

In addition, these more robust ragweed plants sent more pollen into the atmosphere at earlier dates where urbanization had occurred. As part of the study, the Department of Biology at Macalester College investigated the antigen E (allergenicity) content of the pollen grains at the four locations.

"We took the unusual step in this study of actually measuring the allergy-causing protein contained in the pollen grains," said Gebhard. "Most people would be satisfied with just the pollen counts but we wanted to address the possible objection that the pollen was in some way different between the sites. There were, in fact, some unexpected differences across the transect, but the bottom line is that all the pollen was allergenic."

"The knowledge we gained from this study will be incorporated into SDI's already well-developed expertise and industry-leading pollen forecasting products," Gebhard added.

"While further research needs to be conducted in situ, we would not be surprised to find that warming associated with urbanization has already begun to affect flowering times and pollen production in other allergen-producing plants. If true, it raises public policy issues related to personal health and productivity and the costs, to both the individual and society, to treat any increase in the allergy-suffering population. Obviously, these issues will require additional study," said Ziska.

A complete report on the research was published in the February 2003 issue of the Journal of Allergy and Clinical Immunology (part 1, Vol. 111, No. 2), the peer reviewed journal of the American Academy of Allergy Asthma and Immunology.

Multidata LLC researches and publishes reports on allergy data and trends, including the Allergy Alert(TM) Forecast, for pharmaceutical and media industries. In addition, the company supplies equipment used for pollen and airborne particulate measurement. Its primary product, the Rotorod(R) Sampler, is the industry standard among pollen sampling devices.

SDI is the leading provider of real-time localized illness tracking and modeling data to the pharmaceutical and healthcare industries. Visit www.surveillancedata.com for more information about the company and its products.