Does living close to allergenic street trees affect lung function in German adults?

Area of Science:

• Environmental Health
• Pulmonary Medicine
• Epidemiology

Background:

• Greenspace exposure and adult lung function studies show mixed results.
• Adverse findings may stem from long-term exposure to allergenic tree pollen.
• This research explores the impact of birch and allergenic trees on lung function.

Purpose of the Study:

• To investigate the relationship between proximity to birch or allergenic trees and lung function in adults.
• To determine if these tree exposures confound the association between general greenspace and lung function.

Main Methods:

• Utilized data from 874 adults (aged 20-44) in the ECRHS cohort study.
• Measured spirometric lung function (FEV1, FVC) over three time points (1991/92, 2000/01, 2011/12).
• Quantified tree exposure using registries and assessed greenspace via NDVI, tree cover, and total trees within a 300m buffer; employed linear mixed models.

Main Results:

• Increased numbers of birch trees correlated with decreased forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC).
• Every 10 additional birch trees showed an average decrease of 27.6 mL in FEV1 and 28.2 mL in FVC.
• No significant associations were found for other tree types, total trees, tree cover, or NDVI; birch tree effects were independent of allergic sensitization or environmental factors.

Conclusions:

• Proximity to birch trees demonstrates a long-term adverse association with adult lung function.
• Limitations in tree registries (street trees only) precluded a full assessment of confounding by neighborhood allergenic trees on greenspace effects.