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By Ayurella Horn-Muller (Climate Central) and Brendan Gibbons (Rivard Report)

Angela and Jason Bartels’ children are sensitive to the plant pollens that fill the air around their home in San Antonio, Texas. In past years, their symptoms have felt akin to asthma, leaving them coughing and sometimes struggling to breathe, their mother said.

“This year, it’s their eyes,” Bartels, 36, said of her two oldest children, ages 8 and 6. “Their eyes are so puffy, red and just itchy.”

San Antonio is one of the most challenging cities for spring allergies sufferers, and rising temperatures are making it worse.

City employees work to clear brush from the banks of the San Antonio River at Brackenridge Park.
Credit: Scott Ball/Rivard Report file photo

The health implications mean more than just daily inconveniences. Irritated eyes, sneezing, itchy skin, a stuffy nose and congestion “greatly affects quality of life,” says Dipa Sheth, a senior official in the allergy and immunology division of the Veterans Affairs Medical Center.

“Patients can't sleep as well, they're sneezing, or they are congested at night,” Sheth said. “So they're just very exhausted in the morning. A lot of patients complain of being tired when allergens are around.”

A study led by U.S. Department of Agriculture research plant physiologist Lewis Ziska linked the ongoing rise in temperatures across the Northern Hemisphere to long-term pollen impacts in areas where frost-freeze growing seasons are increasing.

“The further north you go, the greater the effect of recent climate change on the duration of the pollen season,” Ziska said.

Millions of residents in a fast-growing corridor of Central Texas from San Antonio to Austin are affected by some of America’s worst allergies from tree and grass pollen. The area has three main allergy seasons – mountain cedar in the winter, oak in the spring, and ragweed in the fall.

These seasons trigger allergic asthma, which affects upwards of 15 million Americans, and more common cases of hay fever, which strikes more than 3 million each year. The numbers are projected to grow, with research estimating high levels of greenhouse gas pollution would worsen respiratory allergies for around 50 million Americans every year.

Poverty, Race and Asthma

In children, conditions like asthma and eczema can also be closely tied to seasonal allergies. For some families, especially those struggling without access to regular medical care and asthma medication, asthma attacks can threaten young lives while draining family budgets.

Oak tree flowers, known as catkins, littering a parking lot in San Antonio.
Credit: Bonnie Arbittier/Rivard Report

Asthma triggered by seasonal allergies costs Americans $18 billion to manage annually — something that hits residents of San Antonio particularly hard, as the city struggles with persistent poverty.

“What we're noticing is that prevalence rates of asthma tend to be highest for low-income minority children,” said Harvard’s Brigham and Women’s Center allergist Margee Louisias, who analyzes allergy prevalence and access to treatment in inner cities across the U.S.  

In low-income, urban areas, at least a quarter of residents can suffer from asthma, says Louisias — more than double the overall national average. The American Journal of Respiratory and Critical Care Medicine also found in a 2012 study on health disparities that asthma mortality rates are nearly three-fold higher in non-Hispanic blacks than non-Hispanic whites.

That means allergies are particularly a threat for cities like San Antonio, which has among the highest rates of uninsured residents in U.S. metropolitan areas.

“These communities, in addition to having higher prevalence rates of asthma, tend to also have worse outcomes,” Louisias said. “They are more likely to be hospitalized, more likely to go to the ER, more likely to die.”

A Change is in the Air

An associate professor of environmental, occupational and global health at George Washington University, Susan Anenberg investigated links between rising pollen counts and public health. She has found oak, birch and grass pollen to be the culprits behind about 4 percent of the 1.6 million asthma-related emergency department visits annually.

Using climate projections, her research warned of a 14 percent increase in pollen-associated emergency department visits by 2090 if little effort is made to reduce emissions of heat-trapping pollution by switching to clean energy and protecting forests and other landscapes. “This is a health outcome of climate change that has not been widely recognized,” Anenberg said.

Temperature data analyzed by Climate Central shows San Antonio’s growing season has increased by nearly four weeks since 1970 — one of the biggest jumps nationwide. With worse ahead, doctors who treat allergy patients in San Antonio, long a pollen epicenter, say they’ve already noticed the problem intensifying.

A longer growing season in San Antonio means a longer allergy season.
Read the full Climate Central report, POLLEN PROBLEMS: Climate Change, the Growing Season, and America’s Allergies.

University of North Carolina School of Medicine adjunct professor and former president of the American Academy of Allergy, Asthma and Immunology, David Peden said by 2050 he expects a 10 to 20 percent increase in Americans affected by a respiratory allergy. “Their seasons will be longer and so the periods of relief from that will be less.”

It’s not just the longer growing seasons — the heat-trapping carbon dioxide released by burning fossil fuels and other industrial activities acts as a fertilizer. 

“With more [carbon dioxide], weeds grow faster, and you have a longer growing season and less winter,” said local ear, nose, and throat doctor John Edwards. “And people’s symptoms all get worse.”

Erika Gonzalez-Reyes, a San Antonio allergy, asthma, and immunology specialist, said she and her colleagues will often “track the pollen levels and see if it’s going to be a busy day.”

During the winter mountain cedar season, which is one of the region’s worst allergy periods, Gonzalez-Reyes said patients typically see her starting in mid-December to mid-February. But over the past three to four years, she’s noticed people coping with cedar allergies as early as the beginning of December.

“You’ll hear anybody in any city say, ‘We’re the worst for allergies,’” Gonzalez-Reyes said. “The difference in a lot of these places is they get a break during the winter. Because of our climate, San Antonio doesn’t really get a break.”