A recent study in the European Respiratory Journal discovered that children who are exposed to tree and weed pollen in urban areas have a higher risk of respiratory issues, such as asthma. While green spaces in cities can reduce exposure to air pollution, promote physical activity for kids, and provide exposure to a wide range of microorganisms that can positively influence a child’s immune system, they can also contribute to the development of childhood asthma. However, trees can help lessen this impact to some extent due to their canopy.Children who are exposed to tree and weed pollen in urban areas face an increased risk of respiratory issues such as asthma. While green spaces in urban settings can reduce exposure to air pollution, encourage physical activity for kids, and provide beneficial contact with a diverse range of microorganisms, this can also lead to the development of childhood asthma. Fortunately, trees can help lessen this impact to some extent, thanks to their canopy. “We discovered that tree canopy provides some protective effects against the development of asthma in children.The study’s lead author, Éric Lavigne, who is an Adjunct Professor in the School of Epidemiology and Public Health at the University of Ottawa, states that the protective effect against childhood asthma disappears with increased exposure to weed pollen. The researchers examined data from the Ontario ASTHMA cohort database, analyzing information over an eight-year span to identify instances of childhood asthma from birth to age six. Out of the 214,000 mother-child pairs in the study, just over 13 percent were diagnosed with childhood asthma. Environmental exposure was measured using the normalized difference vegetation index (NDVI) in addition to other parameters.The study looked at tree canopy coverage within a 250-meter radius of a child’s postal code at birth.
The surprising results found that the presence of green spaces in cities can actually increase pollen exposure and reduce the protection provided by tree canopies.
As there is a growing emphasis on increasing urban greenery, Lavigne suggests that the public should be mindful of the impact of trees in urban areas, including the potential effects of pollen on children’s respiratory health, particularly in relation to the increased risk of asthma.
These findings could have implications for urban planners and public health officials involved in the redevelopment of urban areas.Lavigne, a Senior Epidemiologist at Health Canada, emphasizes the importance of pollen control programs and strategic tree planting to minimize allergic reactions. It’s crucial to consider tree species that produce less allergenic pollen.
