Endotoxin and Der P1 Allergen Levels in Indoor Air and Settled Dust in Day-Care Centers in Tehran, Iran Publisher



Shahhosseini E¹ ; Naddafi K^{1, 2} ; Nabizadeh R^{1, 2} ; Shamsipour M³ ; Namvar Z⁴ ; Tayebi B⁵ ; Shoormasti RS⁵ ; Hassanvand MS² ; Yunesian M^{1, 2} Show Affiliations
Source: Journal of Environmental Health Science and Engineering Published:2019

Abstract

Background: 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. Methods: 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. Results: 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. Conclusion: 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. © 2019 Springer Nature Switzerland AG.