Nasal allergy-like symptoms aggravated by ozone exposure in a concentration-dependent manner in guinea pigs

Abstract

Our previous study revealed that exposure to 0.4 ppm ozone (O(3)) enhanced nasal allergy-like reactions in guinea pigs. In the present study, we investigated the concentration-dependency of the effects of exposure to O(3) on the aggravation of nasal allergy-like reactions induced by repeated nasal administration of antigen. Guinea pigs were exposed to filtered air or 0.1-0.6 ppm O(3) for 5 weeks. After each weekly administration of ovalbumin (OVA), sneezes and nasal secretions were measured. The number of eosinophils infiltrating the nasal septum and the titers of OVA-specific antibody were measured 24h after the last administration. Ozone increased sneezing and nasal secretion induced by OVA, nasal responsiveness to physical stimuli, and the number of infiltrating eosinophils in a concentration-dependent manner. The titer of anti-OVA-IgG was increased in animals exposed to 0.6 ppm O(3). Thus, exposure to O(3) aggravated nasal allergy-like symptoms concentration dependently. The aggravation was caused by induction of nasal hyperresponsiveness, the infiltration of eosinophils, and the increase in the production of anti-OVA-IgG. The estimated maximum likelihood estimation concentrations (MLECs) and bench mark concentrations (BMCs) of O(3) for these indices were in the range of 0.09-0.18 and 0.02-0.06 ppm, respectively.

Release behaviour of cryptomeria japonica pollen allergenic cry J 1 and cry J 2 in rainwater containing air pollutants

“…Thus, the most airborne Cryptomeria japonica pollen grains in Kanto urban area are transported from mountain areas, several hundred kilometres away [4]. Worsening of pollinosis symptoms is induced by introducing allergenic species that coexist with air pollutants such as gases [5,6], polycyclic aromatic hydrocarbons (PAHs) [7], metallic particles [8,9] carbon aggregates [10], and known adjuvants [11]. It was also reported that small-sized pollen allergenic species adhere to carbon aggregates from vehicle emissions scattered in the atmosphere [12].…”