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The Problem

Warming temperatures are contributing to longer and more intense pollen seasons, which can worsen allergy and asthma symptoms in children.

Climate Change, Pollution, and Allergens

  • Increased CO2 concentration leads to prolonged pollination periods in plants, causing faster and larger growth of plants as well as rise in potency of the pollen allergen, which is known to cause allergies and inflammation

  • The average annual growing season has lengthened by approximately 11 days since the 1960s, creating more opportunity for allergens to persist longer than in previous years

  • High levels of vehicle emissions are linked to rising frequency of respiratory allergic diseases and asthma in industrialized countries

Projections and Impact

Unchecked global warming will worsen respiratory allergies for approximately 25 million Americans. Scientists predict that average pollen counts in 2040 will be more than double what they were in 2000. Thus, at this rate, we can expect markedly increased outbreaks of allergies and an increase in the already large healthcare expense that comes with it.

Young man sneezes because of an allergy to ragweed.jpg

Hay Fever (An Example)

  • One allergic process that affects many and has high costs

  • Caused by ragweed, which has shown to be particularly more potent with increasing temperatures

  • Affects 18.0 million adults and 7.1 million children (9% of kids) in the United States

  • 13.1 million doctor’s visits for hay fever each year

  • $11.2 billion in medical costs to treat allergic rhinitis each year, which hay fever is a cause of

  • $700 million in lost productivity due to hay fever allergies each year

Additional Risks

Pollen is not the only natural allergen that global warming might intensify. Poison ivy plants exposed to more carbon dioxide produced a more allergenic form of urushiol, the substance responsible for the itchy response or contact dermatitis, which is also discussed under the 'Skin Disease' tab on this site. Also, fungal spores, which can cause allergic and asthmatic reactions in both outdoor and indoor air, become more abundant as carbon dioxide and temperatures increase.

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