Seasonal variation in (1→3)-β-D-glucan levels with health risk assessment and related factors in indoor environments of microbiology laboratories

Abstract

ABSTRACT(1→3)-β-D-glucan causes respiratory airway irritation as a biomarker for biological agents in indoor environments. We evaluated (1→3)-β-D-glucan levels in three microbiology laboratories every month for one year by applying a health risk assessment methodology and determined the associated environmental factors. In total, 192 samples were retrieved using a new, two-stage bioaerosol cyclone (BC 221) sampler. Analysis of (1→3)-β-D-glucan was performed using the kinetic Limulus amebocyte lysate assay. This study revealed that illumination was negatively correlated with (1→3)-β-D-glucan (r = −0.206, p = 0.04) and that relative humidity and season were positively associated with (1→3)-β-D-glucan (p < 0.05). Among the environmental factors, season (particularly spring) was most significantly associated with (1→3)-β-D-glucan levels. Future studies regarding the relationship between (1→3)-β-D-glucan levels and other biological agents, including fungi, bacteria, endotoxin, and other environmental factors, should be assessed. The hazard quotient in summer is higher than the acceptable level of 1 for children if they stay in laboratories for 12 hours. Inhalation exposure to (1→3)-β-D-glucan by children in microbiology laboratories is thus not safe in summer.