'Tis the season of warmer temperatures, blue skies, and the slow shedding of layers. While I, like many others, welcome this warmer weather, I am also weary of how unseasonably warm the winter has been. This past January was the on record. The same goes for .
Climate change is one of the main driving forces behind these record heat trends. Its impact on temperature and precipitation patterns is worsening summer heat extremes, intensifying wildfire seasons, and changing the spread of some infectious diseases. Clinicians are seeing the health consequences of these environmental changes reflected in their patients' health.
As an ENT physician, one of my main concerns is patients with . With spring right around the corner, it's important to consider my patients with pollen allergies and how their symptoms.
How Does Climate Change Impact Pollen Allergies?
In the spring, tree pollen is the dominant pollen. Global warming impacts pollen allergies in a few different ways. First, the "freeze free" season (i.e. the season in which the ground thaws and plants/trees can grow) is longer now than it used to be. This allows plants to bloom earlier, which introduces tree pollen earlier than it used to. One showed that in North America, the pollen season is on average about 20 days longer now than it was in 1990. The length of the pollen season varies by geographic location, with this graph from (an independent group of scientists and climate communicators who research the impacts of climate change), showing how different areas are impacted by changes in pollen season length.
Climate change also contributes to in pollen concentration, which can introduce pollen to new regions previously unexposed. This may cause people who have not experienced pollen allergies previously to become sensitized and start having symptoms.
Changes in temperature and precipitation patterns related to climate change have also been increased levels of atmospheric pollen and increased allergenicity of pollen. One of the factors thought to be contributing to higher pollen counts is the increased concentration of carbon dioxide in the atmosphere. Carbon dioxide is one of the main heat-trapping gases that is emitted when fossil fuels are burned. Its is currently at 423 ppm. In 2000, the level was at 369 ppm.
Climate change not only worsens allergies through its impact on pollen concentrations, it also does so indirectly by increasing flooding risk. Flooding is associated with a higher degree of indoor mold and spore production, which is a common allergen that exacerbates allergic rhinitis and increases asthma risk.
Why Does This Matter?
Approximately in the U.S. have seasonal allergies. Allergies have a significant negative impact on quality of life due to symptoms of increased nasal congestion, fatigue, nasal drainage, and poor sleep quality. Furthermore, allergen exposure increases the risk of some respiratory diseases, including asthma exacerbations due to allergic asthma.
Clinicians who treat allergic airway disease and patients who have allergies are both increasingly recognizing that allergy symptoms are worsening. Climate change is a modifiable risk factor that is contributing to this trend, and we have an opportunity to help address this.
What Can We Do About It?
This is a question I ask myself a lot. There are the "immediate" recommendations for every patient. This includes optimizing allergy medication dosing and timing, checking pollen counts before heading outdoors, washing clothes, and keeping windows closed. These recommendations are incredibly important for helping patients manage their environmental allergies on a day to day basis.
Along with managing the "now," we should anticipate and address future trends. We know that climate change is changing of pollen allergies. There are many different approaches to this (i.e. to climate action), and it can be hard to pick one, or figure out what will be most impactful.
James Clear writes in the book Atomic Habits, "Every action you take is a vote for the type of person you wish to become." I offer a slight variation of his advice, "Every climate action is a vote for the type of future we want to live in."
Climate action comes in many forms. As marine biologist and policy expert Ayana Johnson, PhD, advises, of what you are good at, what brings you joy, and what the climate crisis needs.
Personally, I have found that specific actions are both effective and straightforward for me to do. For example, volunteering with the , a nonpartisan organization focused on mobilizing environmental voters, is highly impactful and can be done relatively easily. I have also found that joining forces with other clinicians to advocate for state-based climate legislation () is important in getting state-based climate policy passed. Another option is to simply talk about it. Engaging with patients in the clinic, colleagues at the hospital, and with family helps raise awareness about why climate change is a health concern, and what we need to do to stop its impacts on our patients' health.
Climate change is happening and has direct consequences for our patients, including worsening their allergies and respiratory symptoms. While adapting to these environmental changes is important for health, now is the time to prioritize mitigation measures and address climate change in order to lessen its impact on health.
Neelu Tummala, MD, is an ENT physician, assistant professor of surgery at the George Washington School of Medicine & Health Sciences, and co-director of the Climate Health Institute at George Washington University in Washington, D.C.