Endotoxin and Der p1 allergen levels in indoor air and settled dust in day-care centers in Tehran, Iran
Allergens like endotoxin and mite allergen Der p 1 are associated with early wheezing and asthma morbidity. Day-care centers can be an important source of exposure to allergens. The aim of this study was to evaluate children’s exposure to endotoxin and mite allergen (Der p 1) associated with total suspended particulate matter (TSP) and settled dust in day-care centers in two phases in years of 2015 and 2016 in Tehran city, Iran.
Endotoxin and mite allergen Der p 1 in TSP and settled dust were measured in 23 day-care centers in Tehran. After collecting dust samples and weighting them, and then their extraction, Endotoxin and Der p 1 allergen were determined using QCL-1000 Endpoint chromogenic LAL Assay and ELISA, respectively.
The mean concentrations of endotoxin and mite allergen Der p 1 in settled dust were 0.3 EU/mg and 0.2 ng/mg, respectively. The mean concentration of endotoxin and mite allergen Der p 1 in indoor air TSP were 0.8 EU/m3 and 0.4 ng/m3, respectively. A significant negative correlation was found between endotoxin both in settled dust and in TSP with measured relative humidity in winter. Also, moderate correlation was observed between Der p 1 in settled dust and relative humidity in winter; however, the correlation between allergen in TSP and relative humidity was not significant.
Day-care centers can be an important source of endotoxin and Der p 1 allergen, so, implementation of proper interventions in these places can reduce exposure to them.
KeywordsIndoor air Endotoxin Der p 1 Mite allergen Day-care centers Tehran
The authors acknowledge the Institute for Environmental Research (IER) of Tehran University of Medical Sciences for technically and financially supporting this research (grant number 93-03-46-27166). The authors also thank to the administrations of day-care centers for their cooperation.
This study was funded by Institute for Environmental Research (IER) of Tehran University of Medical Sciences (grant number 93–03–46-27166).
Compliance with ethical standards
There is no actual or potential conflict of interest among authors.
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