Cristiana Pereira

Indoor Air Quality and Thermal Comfort—Results of a Pilot Study in Elderly Care Centers in Portugal

The age of the European population is rising and percentage of adults aged 65 years and older is projected to increase from 16% in 2000 to 20% in 2020. It has been estimated that older subjects spend approximately 19 to 20 h/d indoors. Older individuals may be particularly at risk for detrimental effects from pollutants, even at low concentrations, due to reduced immunological defenses and multiple underlying chronic diseases. Six Porto, Portugal, urban area elderly care centers (ECC), housing a total of 425 older persons, were studied to assess indoor air quality (IAQ) and thermal comfort (TC) in two seasons. This study presents the IAQ and TC results in 36 rooms and constitutes part of a wider and ongoing study. The study areas were all naturally ventilated, and indoor concentrations in winter were within Portuguese reference values. However, 42% of the participants were dissatisfied with indoor thermal conditions, rating it “slightly cool.” In summer, the index rate of dissatisfied individuals was lower (8%). Significant differences were found between seasons in predicted percent of dissatisfied people (PPD) and predicted mean vote (PMV) indices. Fungal concentrations frequently exceeded reference levels (>500 colony-forming units [CFU]/m3). In addition, other pollutants occasionally exceeded reference levels. To our knowledge, this is the first study in Portugal to assess effects of indoor air contaminants on the health status and quality of life in older subjects living in ECC. Although IAQ and TC parameters were mostly within reference values, the results suggest a need to improve the balance between IAQ and TC in ECC, a critical environment housing a susceptible population.

Oxidative Stress and DNA Damage: Implications in Inflammatory Bowel Disease.

Abstract:This review will focus on published human studies on oxidative stress and DNA damage in inflammatory bowel disease (IBD), both ulcerative colitis and Crohns disease, assessing their role in the pathophysiology of these diseases. Search was performed over PubMed and ScienceDirect databases to identify relevant bibliography, using keywords including “oxidative stress,” “DNA damage,” “IBD,” and “oxidative DNA damage.” Whether as cause or effect, mechanisms underlying oxidative stress have the potential to condition the course of various pathologies, particularly those driven by inflammatory scenarios. IBDs are chronic inflammatory relapsing conditions. Oxidative stress has been associated with some of the characteristic clinical features exhibited in IBD, namely tissue injury and fibrosis, and also to the ulcerative colitis–associated colorectal cancer. The possible influence of oxidative stress over therapeutic behavior and response, as well as their contribution to the oxidative burden and consequences, is also addressed. Due to the high prevalence and incidence of IBD worldwide, and also to its associated morbidity, complications, and disease and treatment costs, it is of paramount importance to better understand the pathophysiology of these diseases.

Environmental and Ventilation Assessment in Child Day Care Centers in Porto: The Envirh Project

Children attending day care centers (CDCC) have been reported to be more prone to infectious diseases when compared with those cared for at home, and are exposed to conditions that may increase the risk of allergies and asthma. Several studies revealed that consequences of poor ventilation conditions include high levels of carbon dioxide (CO2) and many other indoor pollutants commonly detected in schools. Nine child day care centers were selected randomly to participate in this study. Fifty-two classrooms were assessed for chemical, biological, physical, and allergen parameters in spring and winter seasons in these nine CDCC located in Porto, Portugal. Outdoor measurements were also conducted for comparison. Our results indicated that (i) particulate matter (PM10) median levels were above the national reference levels, both by classroom type and by season; (ii) TVOC kindergarten peak values may raise some concern; (iii) CO2 was present at high median and maximum levels during spring and winter assessment in both nurseries and kindergartens classrooms; (iv) total bacteria concentrations were 57- and 52-fold higher in the nursery and kindergarten than outdoors, respectively, for the spring season; (v) winter and spring median predicted mean vote (PMV) indices were between “neutral” (0) and “slightly cool” (≤ –1) in the thermal sensation scale for comfort situations (−2 to 2) for both types of classrooms; (vi) there were significant differences for both PMV and predicted percentage of dissatisfied (PPD) indices by season; and (vii) CO2, total bacteria, and gram-negative bacteria were associated with low airflow rates. These data will help to evaluate the effectiveness of current building operation practices in child day care centers regarding indoor air quality and respiratory health.

Identification and Levels of Airborne Fungi in Portuguese Primary Schools

Several studies found associations between exposure to airborne fungi and allergy, infection, or irritation. This study aimed to characterize airborne fungi populations present in public primary schools in Porto, Portugal, during winter through quantification and identification procedures. Fungal concentration levels and identification were obtained in a total of 73 classrooms. The AirIdeal portable air sampler was used in combination with chloramphenicol malt extract agar. Results showed a wide range of indoor fungi levels, with indoor concentrations higher than outdoors. The most prevalent fungi found indoors were Penicillium sp. (>70%) and Cladosporium sp. As evidence indicates that indoor fungal exposures plays a role in asthma clinical status, these results may contribute to (1) promoting and implementing public health prevention programs and (2) formulating recommendations aimed at providing healthier school environments.

Children's health and indoor air quality in primary schools and homes in Portugal-Study design

The main aim of the research project “On the Contribution of Schools to Children’s Overall Indoor Air Exposure” is to study associations between adverse health effects, namely, allergy, asthma, and respiratory symptoms, and indoor air pollutants to which children are exposed to in primary schools and homes. Specifically, this investigation reports on the design of the study and methods used for data collection within the research project and discusses factors that need to be considered when designing such a study. Further, preliminary findings concerning descriptors of selected characteristics in schools and homes, the study population, and clinical examination are presented. The research project was designed in two phases. In the first phase, 20 public primary schools were selected and a detailed inspection and indoor air quality (IAQ) measurements including volatile organic compounds (VOC), aldehydes, particulate matter (PM2.5, PM10), carbon dioxide (CO2), carbon monoxide (CO), bacteria, fungi, temperature, and relative humidity were conducted. A questionnaire survey of 1600 children of ages 8–9 years was undertaken and a lung function test, exhaled nitric oxide (eNO), and tear film stability testing were performed. The questionnaire focused on children’s health and on the environment in their school and homes. One thousand and ninety-nine questionnaires were returned. In the second phase, a subsample of 68 children was enrolled for further studies, including a walk-through inspection and checklist and an extensive set of IAQ measurements in their homes. The acquired data are relevant to assess children’s environmental exposures and health status.

Exposure of Children to Ultrafine Particles in Primary Schools in Portugal

Children spend a large part of their time at schools, which might be reflected as chronic exposure. Ultrafine particles (UFP) are generally associated with a more severe toxicity compared to fine and coarse particles, due to their ability to penetrate cell membranes. In addition, children tend to be more susceptible to UFP-mediated toxicity compared to adults, due to various factors including undeveloped immune and respiratory systems and inhalation rates. Thus, the purpose of this study was to determine indoor UFP number concentrations in Portuguese primary schools. Ultrafine particles were sampled between January and March 2014 in 10 public primary schools (35 classrooms) located in Porto, Portugal. Overall, the average indoor UFP number concentrations were not significantly different from outdoor concentrations (8.69 × 103 vs. 9.25 × 103 pt/cm3, respectively; considering 6.5 h of indoor occupancy). Classrooms with distinct characteristics showed different trends of indoor UFP concentrations. The levels of carbon dioxide were negatively correlated with indoor UFP concentrations. Occupational density was significantly and positively correlated with UFP concentrations. Although the obtained results need to be interpreted with caution since there are no guidelines for UFP levels, special attention needs to be given to source control strategies in order to reduce major particle emissions and ensure good indoor air quality.

Students’ game performance improvements during a hybrid sport education–step-game-approach volleyball unit

The purpose of this study was to examine a hybrid combination of sport education and the step-game-approach (SGA) on students’ gameplay performance in volleyball, taking into account their sex and skill-level. Seventeen seventh-grade students (seven girls, 10 boys, average age 11.8) participated in a 25-lesson volleyball season, in which the structural features followed those of sport education and the specific content followed the didactical framework of the SGA. Data were collected prior to the first lesson (pre-test), following the completion of the unit (post-test) and seven days after the post-test (retention). The game performance assessment instrument was used in a systematic observation of video records of students’ behaviours while playing a 10-minute 2vs2 game. A 2 (sex) × 3 (time) and a 2 (skill-level) × 3 (time) analysis of variance (ANOVA) with repeated measures across the three tests was used to compare the students’ performances on all indexes. Results showed that both boys and girls made improvements from the pre-test to the post-test and maintained those improvements to the retention test in almost all the indexes analysed. Further, the results also showed that lower skill-level students realized greater gains than those of higher skill during the unit, which reinforces the idea that future implementations of this hybrid approach should adjust content and learning task to different skill-levels.

Moving into advanced nanomaterials. Toxicity of rutile TiO2 nanoparticles immobilized in nanokaolin nanocomposites on HepG2 cell line

Abstract Immobilization of nanoparticles on inorganic supports has been recently developed, resulting in the creation of nanocomposites. Concerning titanium dioxide nanoparticles (TiO2 NPs1), these have already been developed in conjugation with clays, but so far there are no available toxicological studies on these nanocomposites. The present work intended to evaluate the hepatic toxicity of nanocomposites (C‐TiO22), constituted by rutile TiO2 NPs immobilized in nanokaolin (NK3) clay, and its individual components. These nanomaterials were analysed by means of FE‐SEM4 and DLS5 analysis for physicochemical characterization. HepG2 cells were exposed to rutile TiO2 NPs, NK clay and C‐TiO2 nanocomposite, in the presence and absence of serum for different exposure periods. Possible interferences with the methodological procedures were determined for MTT,6 neutral red uptake, alamar blue (AB), LDH,7 and comet assays, for all studied nanomaterials. Results showed that MTT, AB and alkaline comet assay were suitable for toxicity analysis of the present materials after slight modifications to the protocol. Significant decreases in cell viability were observed after exposure to all studied nanomaterials. Furthermore, an increase in HepG2 DNA damage was observed after shorter periods of exposure in the absence of serum proteins and longer periods of exposure in their presence. Although the immobilization of nanoparticles in micron‐sized supports could, in theory, decrease the toxicity of single nanoparticles, the selection of a suitable support is essential. The present results suggest that NK clay is not the appropriate substrate to decrease TiO2 NPs toxicity. Therefore, for future studies, it is critical to select a more appropriate substrate for the immobilization of TiO2 NPs. HighlightsOnly the MTT and AB assays were found to be suitable for cytotoxicity assessment.Alkaline comet assay was also appropriate for genotoxicity evaluation.All nanomaterials decreased the HepG2 cell viability and caused DNA damage.Nanokaolin is not a suitable clay substrate for the immobilization of TiO2 NPs.Further toxicity studies must be performed in other clays to support nanoparticles.

Biological Air Contamination in Elderly Care Centers: Geria Project

Indoor air quality (IAQ) affects health particularly in susceptible individuals such as the elderly. It has been estimated that the older population spends approximately 19–20 h/d indoors, and the majority of the elderly spend all of their time indoors in elderly care centers (ECC). Older individuals may be particularly at risk of exposure to detrimental effects from pollutants, even at low concentrations, due to common and multiple underlying chronic diseases that increase susceptibility. This study, aimed to assess the impact of indoor biological agents in 22 ECC located in Porto, was conducted during summer and winter from November 2011 to August 2013 at a total of 141 areas within dining rooms, drawing rooms, medical offices, and bedrooms (including the bedridden). Air sampling was carried out with a microbiological air sampler (Merck MAS-100) and using tryptic soy agar for bacteria and malt extract agar for fungi. The results obtained were compared with the recently revised Portuguese standards. In winter, mean fungi concentration exceeded reference values, while bacteria concentrations were within the new standards in both seasons. The main fungi species found indoors were Cladosporium (73%) in summer and Penicillium (67%) in winter. Aspergillus fumigatus, Aspergillus niger, and Aspergillus flavus, known potential pathogenic/toxigenic species, were also identified. Although the overall rate and mean values of bacteria and fungi found in ECC indoor air met Portuguese legislation, some concern is raised by the presence of pathogenic microorganisms. Simple measures, like opening windows and doors to promote air exchange and renewal, may improve effectiveness in enhancing IAQ.

Indoor fungal diversity in primary schools may differently influence allergic sensitization and asthma in children

Childhood exposure to microbiologic agents may influence the development of allergic and respiratory diseases. Apart from home, children spend most of their time at school, which represents an environment of significant exposure to indoor air microbes. Therefore, we aimed to assess how the prevalence of allergic sensitization and asthma in schoolchildren is affected by microbiologic exposure within classrooms.