Endotoxin is the constituent of the cell wall of gram-negative bacteria that initiates the inflammatory response. Previous studies showed consistent results that airborne endotoxin exposure may increase the risk of respiratory symptoms in children. Moreover, previous studies displayed that the air pollutants- nitrogen dioxide (NO)and nicotine may modify the association between airborne endotoxin and asthma outcome (acute visit, symptoms, etc.) and airway inflammation (the fractional concentration of exhaled nitric oxide) in children
So far, limited studies have explored the effects of interactions between airborne endotoxin and air pollutants. The team led by Pei-Shih Chen, the Chair of Public Health of Kaohsiung Medical University, evaluated whether indoor air pollutants in a heavy industrial city, including NO2, PM, the carbon monoxide (CO), carbon dioxide (CO2), sulfur dioxide (SO2), and ozone (O3), can modify the association between indoor airborne endotoxin and lung function. 120 elementary school-age children in Kaohsiung City, Taiwan was recruited. Airborne endotoxin and air pollutants were collected for 24 hours in living rooms while schoolchildren’s lung function was measured. The modification of air pollutants on the relationship between airborne endotoxin and children’s lung function was estimated after adjusting the gender, age, height, weight, and case-control status. The team in collaborating with Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, University of Texas Health Science Center at Houston, TX, United States, found that household O3 and PM can modify the association between household airborne endotoxin and lung functions. Our findings suggest that the combination of higher concentrations of O3 or PM10 exposure and concomitant indoor airborne endotoxin exposure may affect schoolchildren’s lung function in a heavy industrial city. These findings also highlight the importance of understanding the complexity of indoor exposures and their effects on lung functions to develop effective approaches to environmental control. The results have been published in the journal Science of the Total Environment .