Indoor air quality (IAQ) has become a major concern nowadays because of the universality of exposure and its potential negative impact on human health especially on children. This study is intended to explore the association between IAQ and the respiratory health among preschool children in urban and suburban area. A cross-sectional comparative study was carried out among Malay preschool children in urban (N= 60, Puchong) and suburban (N=60, Hulu Langat) areas. An indoor air quality assessment was conducted in 12 preschools and 60 houses which include parameters of PM2.5, PM10, VOCs, mold, bacteria, Gram-negative bacteria and physical parameters. A set of standardized questionnaire was distributed to obtain respondents’ background information, exposure history and respiratory health symptoms. Spirometry test was carried out and the data obtained were analyzed to determine the lung function of the respondents. There was a significant difference between IAQ in urban and suburban preschools for all parameters measured (p<0.05). Most of the pollutants were significantly associated with respiratory health symptoms. There was a significant association between the level of indoor pollutants with the lung function abnormalities among the respondents. Even though this study is the first to take Gram-negative bacteria as an indoor air pollutant, the finding also shows that there is a significant association between exposure of Gram-negative bacteria with lung function impairment and higher reported respiratory symptoms among the respondents. The finding concluded that exposures to indoor air pollutants, especially PM2.5 increases the risk of getting lung function abnormality and respiratory health symptoms among respondents.
Indoor air quality ; mold ; bacteria ; lung function ; respiratory health symptoms

Research on environmental ergonomics of train/commuter is very limited. Thus, this study was conducted with aims to determine the environmental ergonomic of public transport, whether it is in accordance to indoor air quality standard inside women coach cabin train during operations. Although the number of passengers is increasing, some claimed that the indoor air quality for the Malaysian commuter train is uncertain, especially at peak times. Unsatisfactory feedback from some respondents—especially female passengers—will affect other passengers to remain loyal to use this facility as one of the main transportation to reduce the traffic congestion that will be faced if using private vehicles. The study conducted during peak hours on the weekends and the trip took exactly two hours and covered 18 main stations. The measurement devices placed at the centre of the cabin Komuter using Air Quality Meter (AIRFLOW Instrument Model TA465). The main parameters measured were temperature, humidity, and carbon dioxide (CO2). This study also counts the number of passengers riding the train. The results showed that the indoor air quality (AIQ) level of the morning hour will affect passengers’ health more compared to the evening hour (this is due to the CO2 level that has exceeded the safety standard). Morning hour gave higher reading of CO2 (43.8%) and relative humidity (17%) compared to evening hour. Evening hours also showed greater temperature at 3%. The findings can give awareness to the train company to improve the IAQ by installing a suitable ventilation system and can give comfort to the passengers when travelling using Malaysian commuter train The results showed that the indoor air quality (AIQ) level of the morning hour will affect passengers’ health more compared to the evening hour (this is due to the CO2 level that has exceeded the safety standard). Morning hour gave higher reading of CO2 (43.8%) and relative humidity (17%) compared to evening hour. Evening hours also showed greater temperature at 3%. The findings can give awareness to the train company to improve the IAQ by installing a suitable ventilation system and can give comfort to the passengers when travelling using Malaysian commuter train.
ergonomic environment ; indoor air quality ; public transport ; KTM Komuter

Indoor air quality is an essential aspect for occupational health including in a densely populated university. This study aimed to assess the indoor airborne microorganisms via biochemical and molecular approaches in five enclosed workplaces, and their resistance towards six commonly used antibiotics. Cfu/dm2/h for five enclosed workplaces was determined using settle plate technique with 1/1/1 scheme and Gram staining was performed for all pure strains isolated. Two strains with the highest count and with different morphologies were identified using biochemical test as well as 16S rRNA amplification and direct sequencing. Minimum inhibitory concentration for antibiotics was carried out for these two strains. In this study, 27 microbial strains with different morphologies were obtained from all workplaces and 2 strains with the highest count were strain J in café and strain M in library, which were identified as Bacillus cereus and Staphylococcus cohnii, respectively. Both of them were highly susceptible to ampicillin and tetracycline. With resistance up to 0.78 µg/mL; B. cereus was less sensitive to kanamycin and neomycin whereas S. cohnii was less sensitive to streptomycin. In conclusion, antibiotics resistant B. cereus and S. cohnii were two of the microorganisms showing the most abundance in the café and library of a Malaysian public university, respectively. This study may serve as the baseline for the prescriptions of antibiotics to airborne microbial related infections especially to the community in the university who seek for medical treatments; particularly for respiratory and digestive infections which often associated with indoor microenvironment.
antibiotic resistance ; Bacillus cereus ; indoor air quality ; minimum inhibitory concentration ; Staphylococcus cohnii

The effects of children’s exposure on high concentration of airborne pollutants at schools often associated with increased rate of absenteeism, low productivities and learning performances, and development of respiratory problems. Recent studies have found that the presence of occupants in the classroom seems to give major effect towards the elevation of concentration of airborne pollutants in indoors. In order to evaluate and further understand on the significance of occupancy factor on IAQ, this study has been designed to determine and compare the level of selected physical (particulate matter (PM)) and chemical (carbon dioxide (CO2) and temperature) IAQ parameters and biological contaminants via colony forming unit (CFUm-3 ) for bacteria and fungi inside the selected classrooms during occupied and non-occupied period (first objective). The second objective is to describe the possible sources of airborne pollutants inside the classrooms at the selected primary schools around Kuantan, Pahang. Assessments of physical and chemical IAQ were done by using instruments known as DustMate Environmental Dust Detector and VelociCalc® MultiFunction Ventilation Meter 9565.The data were recorded every 30 minutes for 8 hours during schooldays and weekend at the selected sampling point in the classrooms. For microbial sampling, Surface Air System Indoor Air Quality (SAS IAQ) was used to capture the bacteria and fungi. The data obtained were compared with the established standard reference known as the Industrial Code of Practice on Indoor Air Quality (2010) constructed by the Department of Occupational Safety and Health (DOSH), Malaysia. This study has found that some of the IAQ parameters in the selected classrooms were exceeding the established standards during occupied period in schooldays compared to non-occupied period during weekend. Findings of this study provide the insights for future research including the site selection of school, arrangement of the classrooms and numbers of students per class.
Occupancy ; particulate matter (PM) ; airborne microbes ; indoor air quality ; primary schools

PURPOSE: The aims of this study were to examine indoor concentrations of air pollutants in socioeconomically disadvantaged houses and to investigate relationships between indoor air pollutant levels and the severity of atopic dermatitis (AD). METHODS: A total of 54 children who had a past history or current symptoms of AD were enrolled in the study. To evaluate the levels of indoor air pollutants, we measured concentrations of CO2, total volatile organic compounds (TVOC), formaldehyde, particulate matter with diameter less than 10 microm (PM10), airborne mold and numbers of house dust mite (HDM) in dust of the children's houses. All studied subjects completed physical examination for the severity of AD and blood tests. RESULTS: Although the mean (+/-standard deviation [SD]) concentration of indoor CO2 (600.6+/-179.4 ppm) was lower than the standard recommended levels of multiplex buildings in Korea, there was a significant correlation between CO2 concentrations and the severity of AD (r=0.302, P=0.030). The geometric means (range of 1 SD) of TVOC (42.5 microg/m3 [22.2-81.5]), formaldehyde (24.3 microg/m3 [15.0-39.9]), PM10 (26.6 microg/m3 [14.6-48.4]), and airborne mold (49.9 CFU [colony forming unit]/m3 [26.3-94.6]) were not significantly higher than the standard recommended levels of multiplex buildings. Two-thirds of the subjects were sensitized to at least 1 of the common allergens. CONCLUSION: Generally, indoor air pollution was not serious in socioeconomically disadvantaged households. However, indoor CO2 concentrations are closely related to the severity of AD in children living in socioeconomically disadvantaged houses. Environmental amelioration targeting vulnerable population may improve the quality of life and decrease the prevalence of environmental allergic diseases.
Air Pollutants* ; Air Pollution, Indoor ; Allergens ; Child* ; Dermatitis, Atopic* ; Dust ; Family Characteristics ; Formaldehyde ; Fungi ; Hematologic Tests ; Humans ; Korea ; Particulate Matter ; Physical Examination ; Prevalence ; Pyroglyphidae ; Quality of Life ; Volatile Organic Compounds ; Vulnerable Populations*