Recent development of communication technology and evolution of telecommunications services, various needs of users are giving Telecom operators difficulties in discovering new services and its promotion strategies. In addition, at the launching of new se

In this study, we estimated nitrogen dioxide (NO₂) concentrations in microenvironments where residential indoor, residential outdoor, other indoors, and transportation using measured personal exposure and multiple linear regression analysis of time-weighted average model, and compared with measured NO₂ concentration in microenvironments. Measured residential indoor, outdoor and other indoor NO₂ concentration was 22.22±9.59 ppb, 23.64±9.62 ppb, and 22.07±13.90 ppb, respectively. NO₂ concentrations in residential indoor and outdoor, total outdoor, other indoor, and transportation by multiple regression analysis were significantly estimated as 20.48 ppb, 32.79 ppb, 24.35 ppb, and 28.82 ppb, respectively (p= 0.000). Measured and estimated NO₂ concentration were similar with each other, therefore NO₂ concentrations in each microenvironment were able to be estimated using time-weighted average model and personal exposure with multiple regression analysis.

Perceived air quality (PAQ) is defined as evaluation of indoor air satisfaction and comfortable sensory by occupants. However, there are differences between criteria of indoor pollutants and lowest sensory thresholds. In this study, we compared indoor PAQ by questionnaire with measured benzene, toluene and nitrogen dioxide (NO2) concentrations in home indoors. The NO2 concentration was the highest in Seoul, while benzene and toluene were the highest in Asan. Average PAQ score in winter was higher than that in summer. Significant correlations between PAQs of home indoor air pollution and measured pollutant concentrations were not shown and correlation coefficients (r) ranged between -0.453<r<0.258. Several groups have been divided to analyze what may affect PAQ scores such as gender, city, home indoor smoking, passive smoking, and self-reported respiratory symptoms. Gender, city, and self-reported respiratory symptoms by indoor air quality were associated with high PAQ scores by using of logistic regression analysis. We are confirmed that no association between concentrations of home indoor pollutant and PAQ scores. Therefore we further need to develop new indicator indoor air pollutants, measurement, and evaluation by PAQ.

This study was performed to determine the effects of genetic polymorphisms, such as glutathione S-transferase μ1 (GSTM1), glutathione S-transferase θ1 (GSTT1), glutathione S-transferase π1 (GSTP1), aryl hydrocarbon N-acetyltransferase 2 (NAT2), cytochrome P450 2E1 (CYP2E1), cytochrome P450 1A1 (CYP1A1) on the concentrations of urinary 1-hydroxypyrene (1-OHP) and 2-naphthol in general population with no occupational exposure to polycyclic aromatic hydrocarbons (PAHs). Study subjects were 257 men who visited a health promotion center in Busan. A questionnaire was used to obtain detailed data about age, smoking, drinking, body fat mass, intake of fat etc. Urinary 1-OHP and 2-naphthol concentration were analyzed by HPLC system with a fluorescence detector. A multiplex PCR method was used to identify the genotypes for GSTM1 and GSTT1. The polymorphisms of GSTP1, NAT2, CYP1A1 and CYP2E1 were determined by the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. Urinary 1-OHP concentration was higher in deleted genotype of GSTM1, increased as smoking and alcohol drinking increased. Urinary 2-naphthol concentration was also rely on the age and smoking. Neither genetic polymorphism nor drinking-related factors were significantly related to urinary 2-naphthol concentration. No significant relation was found between physical characteristics and concentrations of urinary PAHs metabolites in the subjects, but the geometric mean of urinary 1-OHP and 2-naphthol was higher in the group with higher value compared to median value. These data suggest that in general population occupationally not exposed to PAHs, urinary concentration of PAHs metabolites is influenced by smoking, alcohol drinking and deleted genotype of GSTM1 in 1-OHP and smoking in 2-naphthol.