Indoor Air Quality Levels in Schools: Role of Student Activities and No Activities.

This work describes a methodology for the definition of indoor air quality monitoring plans in schools and above all to improve the knowledge and evaluation of the indoor concentration levels of some chemical pollutants. The aim is to guide interventions to improve the health of students and exposed staff connected with the activities carried out there. The proposed methodology is based on the simultaneous study of chemical (indoor/outdoor PM2.5, NO2, CO2) and physical (temperature, humidity) parameters by means of automatic analyzers coupled with gaseous compounds (benzene, toluene, ethylbenzene, xylenes, formaldehyde and NO2) sampled by denuders. The important novelty is that all the data were collected daily in two different situations, i.e., during school activities and no-school activities, allowing us to evaluate the exposure of each student or person. The different behaviors of all the measured pollutants during the two different situations are reported and commented on. Finally, a statistical approach will show how the investigated compounds are distributed around the two components of combustion processes and photochemical reactions.

Air pollution/working activity correlation: a case study in a dental hospital.

The paper deals with a multidimensional approach demonstrating a direct link between the entity of ongoing dentistry activity (number and kind of interventions) and specific pollution components. Simultaneously indoor/outdoor air concentrations of a set of volatile organic compounds (VOCs) and activity variables, describing the amount and nature of ongoing dentistry activities, were monitored over a year at a dental hospital located in an urban area. Principal Component Analysis (PCA) was used to single out mutually orthogonal pollution components which were then correlated to "pathology" factors arising from the analysis of dentistry activity indexes. The use of a multidimensional perspective allowed us to obtain a statistically significant model of the link between level of pollution and dentistry activity. In particular, the correlation approach linking pollution results to pathological variables allows us to establish a causative link even in the presence of sub-threshold concentrations of pollutants.

Correction: Fuselli, et al. A Three Year Study on 14 VOCs at One Site in Rome: Levels, Seasonal Variations, Indoor / Outdoor Ratio and Temporal Trends. Int. J. Environ. Res. Public Health 2010, 7, 3792-3803.

[This corrects the article on p. 3792 in vol. 7.].

A three year study on 14 VOCs at one site in Rome: levels, seasonal variations, indoor/outdoor ratio and temporal trends.

Fourteen volatile organic compounds (VOCs)-twelve hydrocarbons and two organochlorine compounds-were monitored both outdoors and indoors for three years at one site in Rome. Results showed that 118 out of 168 indoor seasonal mean values were higher than the corresponding outdoor concentrations. The most relevant source of outdoor hydrocarbons was automotive exhaust emissions. Due to the enforcement of various measures to protect health and the environment, outdoor levels of monoaromatic hydrocarbons decreased about ten fold over 15 years, and aliphatic hydrocarbons also decreased. With the decrease in these outdoor concentrations, indoor air sources are likely to be more relevant for indoor air exposures. Winter outdoor values for monoaromatic hydrocarbons were generally markedly higher than the summer ones. The gradual replacement of the current fleet of circulating cars with new cars complying with EURO 5 standards, further reducing hydrocarbon emissions, may possibly lead to an increase in the observed indoor/outdoor ratios. It is indeed more difficult to remove indoor sources, some of which are still unknown.

Short-term monitoring of benzene air concentration in an urban area: a preliminary study of application of Kruskal-Wallis non-parametric test to assess pollutant impact on global environment and indoor.

In step with the need to develop statistical procedures to manage small-size environmental samples, in this work we have used concentration values of benzene (C6H6), concurrently detected by seven outdoor and indoor monitoring stations over 12 000 minutes, in order to assess the representativeness of collected data and the impact of the pollutant on indoor environment. Clearly, the former issue is strictly connected to sampling-site geometry, which proves critical to correctly retrieving information from analysis of pollutants of sanitary interest. Therefore, according to current criteria for network-planning, single stations have been interpreted as nodes of a set of adjoining triangles; then, a) node pairs have been taken into account in order to estimate pollutant stationarity on triangle sides, as well as b) node triplets, to statistically associate data from air-monitoring with the corresponding territory area, and c) node sextuplets, to assess the impact probability of the outdoor pollutant on indoor environment for each area. Distributions from the various node combinations are all non-Gaussian, in the consequently, Kruskal-Wallis (KW) non-parametric statistics has been exploited to test variability on continuous density function from each pair, triplet and sextuplet. Results from the above-mentioned statistical analysis have shown randomness of site selection, which has not allowed a reliable generalization of monitoring data to the entire selected territory, except for a single "forced" case (70%); most important, they suggest a possible procedure to optimize network design.

Investigation of indoor air volatile organic compounds concentration levels in dental settings and some related methodological issues.

The assessment of indoor air volatile organic compounds (VOCs) concentration levels in dental settings has a big health relevance for the potentially massive occupational exposure to a lot of diverse contaminants. The comparison of the VOCs profile relative to indoor conditions and to the corresponding outdoor concentrations, as well as the discovery of possible correlations between specific dental activities and VOCs concentration variations are of utmost importance for offering a reliable characterization of risk for dentists and dental staff health. In this study we review the most relevant environmental studies addressing the VOCs contamination level in dental settings. We analyze the methodological problems this kind of study must face and we report preliminary results of an indoor air investigation, carried out at dental hospital in Italy, the "Ospedale odontoiatrico George Eastman" of Rome, in which general lines for the analysis of dental settings in environmental terms are sketched. The aim of this work is to identify the kind of problems a typical enclosed (non-industrial) environment indoor air investigation has to cope with by means of the analysis of a case study.