(Ultra) Fine particle concentrations and exposure in different indoor and outdoor microenvironments during physical exercising.

Although regular exercise improves overall well-being, increased physical activity results in enhanced breathing which consequently leads to elevated exposure to a variety of air pollutants producing adverse effects. It is well-known that one of these ambient air contaminants is ultrafine particles (UFP). Thus, this study aimed to (1) examine exposure to particle number concentrations (PNC) in size ranging from N20-1000 nm in different sport environments and (2) estimate the respective inhalation doses across varying activity scenarios based upon the World Health Organization recommendations for physical activity. PNC were continuously monitored (TSI P-Trak™ condensation particle counter) outdoors (Out1-Out2) and indoors (Ind1-Ind2; fitness clubs) over 4 weeks. Outdoor PNC (total median 12 563 # cm-3; means of 20 367 # cm-3 at Out1 and 7 122 # cm-3 at Out2) were approximately 1.6-fold higher than indoors (total median 7 653 # cm-3; means of 11 861 # cm-3 at Ind1 and 14 200 # cm-3 at Ind2). The lowest doses were inhaled during holistic group classes (7.91 × 107-1.87 × 108 # per kg body weight) whereas exercising with mixed cardio and strength training led to approximately 1.8-fold higher levels. In order to optimize the health benefit of exercises, environmental characteristics of the locations at which physical activities are conducted need to be considered.

Indoor air quality in preschools (3- to 5-year-old children) in the Northeast of Portugal during spring-summer season: pollutants and comfort parameters.

Indoor air quality at schools (elementary, primary) has been the subject of many studies; however, there are still relative few data regarding preschool (3- to 5-year-old children) environments. This investigation determined the concentrations of particulate matter (PM)2.5, total volatile organic compounds (TVOC), formaldehyde, carbon monoxide (CO), and ozone (O3) as well as the levels of carbon dioxide (CO2), temperature, and relative humidity (RH) in the indoor and outdoor air of two preschools situated in different geographical regions of Portugal. The indoor concentrations of TVOC, CO, O3, and CO2 were predominantly higher at the end of school day compared to early morning periods. The TVOC and CO2 concentrations were higher indoors than outdoors suggesting predominantly an indoor origin. Outdoor air infiltrations were the major contributing source of CO and O3 to indoor air in both preschools. The concentrations of all pollutants were within the limits defined by national regulations and international organizations, except for TVOC that exceeded 8-12-fold higher than the recommendation of 0.2 mg/m3 proposed by European Commission. The levels of CO2 were below the protective guideline of 2250 mg/m3 (Portuguese legislation); however, the observed ranges exceeded the Portuguese margin of tolerance (2925 mg/m3) at the end of school days, indicating the impact of occupancy rates particularly at one of the preschools. Regarding comfort parameters, temperature exerted a significant influence on O3 concentrations, while RH values were significantly correlated with TVOC levels in indoor air of preschools, particularly during the late afternoon periods.

Polycyclic aromatic hydrocarbons (PAH) in Portuguese educational settings: a comparison between preschools and elementary schools.

The aim of this study was to determine levels and risks due to inhalation exposure to polycyclic aromatic hydrocarbons (PAH) in different educational settings, namely for 3- to 5- year-old and 6- to 10-year-old children. Eighteen PAH (16 priority designated by US Environmental Protection Agency (USEPA) and dibenzo[a,l]pyrene and benzo[j]fluoranthene) were simultaneously collected in indoor and outdoor air at two Portuguese preschools (PS1-PS2) and five elementary schools (ES1-ES5) from March to May 2014. Indoor concentrations at PS and ES were significantly different, with total levels (∑PAHs) 0.721-15.9 ng/m3 at PS1-PS2 and 5.03-23.6 ng/m3 at ES1-ES5. The corresponding outdoor concentrations were, respectively, 1.22-32.7 ng/m3 and 2.6-31.5 ng/m3. Polycyclic aromatic hydrocarbons with 2-3 aromatic rings were predominantly emitted by indoor sources, while compounds with 4-6 aromatic rings were mainly generated by infiltration of ambient PAH pollution to indoors. Excess lifetime risks of lung cancer exceeded the World Health Organization (WHO) designated guideline of 10-5 in both types of schools (15-42-fold at PS; 15-52-fold at ES). However, total (sum of indoor and outdoor exposure) incremental lifetime cancer risks (ILCR) were below the USEPA level of 10-6 at all studied institutions and thus considered negligible. Finally, ILCR due to indoor exposure represented 60-75% and 70-85% of the total ILCR at PS and ES, respectively, thus indicating the need for development and implementation of indoor air quality guidelines in educations settings.

Children's Indoor Exposures to (Ultra)Fine Particles in an Urban Area: Comparison Between School and Home Environments.

Due to their detrimental effects on human health, scientific interest in ultrafine particles (UFP), has been increasing but available information is far from comprehensive. Children, who represent one of the most susceptible subpopulation, spend the majority of time in schools and homes. Thus, the aim of this study is to (1) assess indoor levels of particle number concentrations (PNC) in ultrafine and fine (20-1000 nm) range at school and home environments and (2) compare indoor respective dose rates for 3- to 5-yr-old children. Indoor particle number concentrations in range of 20-1000 nm were consecutively measured during 56 d at two preschools (S1 and S2) and three homes (H1-H3) situated in Porto, Portugal. At both preschools different indoor microenvironments, such as classrooms and canteens, were evaluated. The results showed that total mean indoor PNC as determined for all indoor microenvironments were significantly higher at S1 than S2. At homes, indoor levels of PNC with means ranging between 1.09 × 10(4) and 1.24 × 10(4) particles/cm(3) were 10-70% lower than total indoor means of preschools (1.32 × 10(4) to 1.84 × 10(4) particles/cm(3)). Nevertheless, estimated dose rates of particles were 1.3- to 2.1-fold higher at homes than preschools, mainly due to longer period of time spent at home. Daily activity patterns of 3- to 5-yr-old children significantly influenced overall dose rates of particles. Therefore, future studies focusing on health effects of airborne pollutants always need to account for children's exposures in different microenvironments such as homes, schools, and transportation modes in order to obtain an accurate representation of children overall exposure.

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 × 10(3) vs. 9.25 × 10(3) pt/cm(3), 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.

Ultrafine particles in ambient air of an urban area: dose implications for elderly.

Due to their detrimental effects on human health, the scientific interest in ultrafine particles (UFP) has been increasing, but available information is far from comprehensive. Compared to the remaining population, the elderly are potentially highly susceptible to the effects of outdoor air pollution. Thus, this study aimed to (1) determine the levels of outdoor pollutants in an urban area with emphasis on UFP concentrations and (2) estimate the respective dose rates of exposure for elderly populations. UFP were continuously measured over 3 weeks at 3 sites in north Portugal: 2 urban (U1 and U2) and 1 rural used as reference (R1). Meteorological parameters and outdoor pollutants including particulate matter (PM10), ozone (O3), nitric oxide (NO), and nitrogen dioxide (NO2) were also measured. The dose rates of inhalation exposure to UFP were estimated for three different elderly age categories: 64-70, 71-80, and >81 years. Over the sampling period levels of PM10, O3 and NO2 were in compliance with European legislation. Mean UFP were 1.7 × 10(4) and 1.2 × 10(4) particles/cm(3) at U1 and U2, respectively, whereas at rural site levels were 20-70% lower (mean of 1 ×10(4) particles/cm(3)). Vehicular traffic and local emissions were the predominant identified sources of UFP at urban sites. In addition, results of correlation analysis showed that UFP were meteorologically dependent. Exposure dose rates were 1.2- to 1.4-fold higher at urban than reference sites with the highest levels noted for adults at 71-80 yr, attributed mainly to higher inhalation rates.

Firefighters' Occupational Exposure in Preparation for Wildfire Season: Addressing Biological Impact.

The characterization of wildland firefighters' occupational exposure must consider different exposures, including those at the fire station. The present study aimed to characterize the occupational exposure of 172 Northern Portuguese wildland firefighters in fire stations during the pre-wildfire season of 2021. The biological impact of estimated inhaled doses of PM10 and PM2.5 (indoor/outdoor) was accessed through a buccal micronucleus cytome (BMCyt) assay in exfoliated buccal cells of a subgroup of 80 firefighters. No significant association was found between estimated inhaled doses of PM10 and PM2.5 (mean 1.73 ± 0.43 µg kg-1 and 0.53 ± 0.21 µg kg-1, respectively) and biological endpoints. However, increased frequencies of cell death parameters were found among subjects of the Permanent Intervention Teams (full-time firefighters). The intake of nutritional supplements was associated with a significant decrease in micronucleus frequencies (i.e., DNA damage or chromosome breakage). In addition, our findings showed a significantly increased frequency of cell death endpoints (i.e., nuclear fragmentation) with coffee consumption, while daily consumption of vegetables significantly decreased it (i.e., nuclear shrinkage). Our results provide data on the occupational exposure of wildland firefighters while working in fire stations during the pre-wildfire season, providing the essential baseline for further studies throughout the wildfire season.

Baseline data and associations between urinary biomarkers of polycyclic aromatic hydrocarbons, blood pressure, hemogram, and lifestyle among wildland firefighters.

Introduction: Available literature has found an association between firefighting and pathologic pathways leading to cardiorespiratory diseases, which have been linked with exposure to polycyclic aromatic hydrocarbons (PAHs). PAHs are highlighted as priority pollutants by the European Human Biomonitoring Initiative in occupational and non-occupational contexts. Methods: This cross-sectional study is the first to simultaneously characterize six creatinine-adjusted PAHs metabolites (OHPAHs) in urine, blood pressure, cardiac frequency, and hemogram parameters among wildland firefighters without occupational exposure to fire emissions (> 7 days), while exploring several variables retrieved via questionnaires. Results: Overall, baseline levels for total OHPAHs levels were 2 to 23-times superior to the general population, whereas individual metabolites remained below the general population median range (except for 1-hydroxynaphthalene+1-hydroxyacenaphtene). Exposure to gaseous pollutants and/or particulate matter during work-shift was associated with a 3.5-fold increase in total OHPAHs levels. Firefighters who smoke presented 3-times higher total concentration of OHPAHs than non-smokers (p < 0.001); non-smoker females presented 2-fold lower total OHPAHs (p = 0.049) than males. 1-hydroxypyrene was below the recommended occupational biological exposure value (2.5 µg/L), and the metabolite of carcinogenic PAH (benzo(a)pyrene) was not detected. Blood pressure was above 120/80 mmHg in 71% of subjects. Firefighters from the permanent intervention team presented significantly increased systolic pressure than those who performed other functions (p = 0.034). Tobacco consumption was significantly associated with higher basophils (p = 0.01-0.02) and hematocrit (p = 0.03). No association between OHPAHs and blood pressure was found. OHPAHs concentrations were positively correlated with monocyte, basophils, large immune cells, atypical lymphocytes, and mean corpuscular volume, which were stronger among smokers. Nevertheless, inverse associations were observed between fluorene and pyrene metabolites with neutrophils and eosinophils, respectively, in non-smokers. Hemogram was negatively affected by overworking and lower physical activity. Conclusion: This study suggests possible associations between urinary PAHs metabolites and health parameters in firefighters, that should be further assessed in larger groups.

Biomonitoring of polycyclic aromatic hydrocarbons exposure and short-time health effects in wildland firefighters during real-life fire events.

Human biomonitoring data retrieved from real-life wildland firefighting in Europe and, also, worldwide are scarce. Thus, in this study, 176 Portuguese firefighters were biomonitored pre- and post- unsimulated wildfire combating (average:12-13 h; maximum: 55 h) to evaluate the impact on the levels of urinary polycyclic aromatic hydrocarbons hydroxylated metabolites (OHPAH; quantified by high-performance liquid chromatography with fluorescence detection) and the associated short-term health effects (symptoms, and total and differentiated white blood cells). Correlations between these variables and data retrieved from the self-reported questionnaires were also investigated. Firefighters were organized into four groups according to their exposure to wildfire emissions and their smoking habits: non-smoking non-exposed (NSNExp), non-smoking exposed (NSExp), smoking non-exposed (SNExp), and smoking and exposed (SExp). The most abundant metabolites were 1-hydroxynaphthalene and 1-hydroxyacenaphthene (1OHNaph + 1OHAce) (98-99 %), followed by 2-hydroxyfluorene (2OHFlu) (0.2-1.1 %), 1-hydroxyphenanthrene (1OHPhen) (0.2-0.4 %), and 1-hydroxypyrene (1OHPy) (0.1-0.2 %); urinary 3-hydroxybenzo(a)pyrene was not detected. The exposure to wildfire emissions significantly elevated the median concentrations of each individual and total OHPAH compounds in all groups, but this effect was more pronounced in non-smoking (1.7-4.2 times; p ≤ 0.006) than in smoking firefighters (1.3-1.6 times; p ≤ 0.03). The greatest discriminant of exposure to wildfire emissions was 1OHNaph + 1OHAce (increase of 4.2 times), while for tobacco smoke it was 2OHFlu (increase of 10 times). Post-exposure, white blood cells count significantly increased ranging from 1.4 (smokers, p = 0.025) to 3.7-fold (non-smokers, p < 0.001), which was accompanied by stronger significant correlations (0.480 < r < 0.882; p < 0.04) between individual and total OHPAH and total white blood cells (and lymphocytes > monocytes > neutrophils in non-smokers), evidencing the impact of PAH released from wildfire on immune cells. This study identifies Portuguese firefighters with high levels of biomarkers of exposure to PAH and points out the importance of adopting biomonitoring schemes, that include multiple biomarkers of exposure and biomarkers of effect, and implementing mitigations strategies.

Assessment of Portuguese fitness centers: Bridging the knowledge gap on harmful microbial contamination with focus on fungi.

The lack of knowledge regarding the extent of microbial contamination in Portuguese fitness centers (FC) puts attendees and athletes at risk for bioaerosol exposure. This study intends to characterize microbial contamination in Portuguese FC by passive sampling methods: electrostatic dust collectors (EDC) (N = 39), settled dust (N = 8), vacuum filters (N = 8), and used cleaning mops (N = 12). The obtained extracts were plated in selective culture media for fungi and bacteria. Filters, EDC, and mop samples' extracts were also screened for antifungal resistance and used for the molecular detection of the selected Aspergillus sections. The detection of mycotoxins was conducted using a high-performance liquid chromatograph (HPLC) system and to determine the cytotoxicity of microbial contaminants recovered by passive sampling, HepG2 (human liver carcinoma) and A549 (human alveolar epithelial) cells were employed. The results reinforce the use of passive sampling methods to identify the most critical areas and identify environmental factors that influence microbial contamination, namely having a swimming pool. The cardio fitness area presented the highest median value of total bacteria (TSA: 9.69 × 102 CFU m-2.day-1) and Gram-negative bacteria (VRBA: 1.23 CFU m-2.day-1), while for fungi it was the open space area, with 1.86 × 101 CFU m-2.day-1. Aspergillus sp. was present in EDC and in filters used to collect settled dust. Reduced azole susceptibility was observed in filters and EDC (on ICZ and VCZ), and in mops (on ICZ). Fumonisin B2 was the only mycotoxin detected and it was present in all sampling matrixes except settled dust. High and moderate cytotoxicity was obtained, suggesting that A549 cells were more sensitive to samples' contaminants. The observed widespread of critical toxigenic fungal species with clinical relevance, such as Aspergillus section Fumigati, as well as Fumonisin B2 emphasizes the importance of frequent and effective cleaning procedures while using shared mops appeared as a vehicle of cross-contamination.

Assessment of indoor air quality in health clubs: insights into (ultra)fine and coarse particles and gaseous pollutants.

Introduction: Exercising on regular basis provides countless health benefits. To ensure the health, well-being and performance of athletes, optimal indoor air quality, regular maintenance and ventilation in sport facilities are essential. Methods: This study assessed the levels of particulate, down to the ultrafine range (PM10, PM2.5, and particle number concentration in size range of 20-1,000 nm, i.e., - PNC20-1000 nm), gaseous pollutants (total volatile organic compounds - TVOCs, CO2, and O3) and comfort parameters (temperature - T, relative humidity - RH) in different functional spaces of health clubs (n = 8), under specific occupancy and ventilation restrictions. Results and Discussion: In all HCs human occupancy resulted in elevated particles (up to 2-3 times than those previously reported), considering mass concentrations (PM10: 1.9-988.5 µg/m3 PM2.5: 1.6-479.3 µg/m3) and number (PNC 1.23 × 103 - 9.14 × 104 #/cm3). Coarse and fine PM indicated a common origin (rs = 0.888-0.909), while PNC showed low-moderate associations with particle mass (rs = 0.264-0.629). In addition, up to twice-higher PM and PNC were detected in cardiofitness & bodybuilding (C&B) areas as these spaces were the most frequented, reinforcing the impacts of occupational activities. In all HCs, TVOCs (0.01-39.67 mg/m3) highly exceeded the existent protection thresholds (1.6-8.9 times) due to the frequent use of cleaning products and disinfectants (2-28 times higher than in previous works). On contrary to PM and PNC, TVOCs were higher (1.1-4.2 times) in studios than in C&B areas, due to the limited ventilations combined with the smaller room areas/volumes. The occupancy restrictions also led to reduced CO2 (122-6,914 mg/m3) than previously observed, with the lowest values in HCs with natural airing. Finally, the specific recommendations for RH and T in sport facilities were largely unmet thus emphasizing the need of proper ventilation procedures in these spaces.

Elemental characterization of indoor breathable particles at a Portuguese urban hospital.

Hospitals are a specific indoor environment with highly susceptible individuals for whom indoor air pollution represents additional health risks. Particulate matter (PM) is one of the most health-relevant indoor pollutants due to its association with respiratory and cardiovascular diseases. Particles can also act as a carrier for various harmful organisms present in the air of hospitals, thus leading to airborne transmission of infectious diseases. Thus, the objective of this study was to characterize indoor PM collected in a hospital in consideration of concentration, size distribution, and elemental composition. Emission sources of indoor PM were indentified and risks associated with indoor PM estimated. Sampling was performed at radiology ward of a Portuguese urban hospital where PM10, PM(2.5), and PM1 were collected during a period of 4 wk; PM elemental composition was determined by proton-induced x-ray emission (PIXE) analysis. Data showed that indoor PM10 concentrations ranged from 13 to 58.8 µg/m³ and from 10.5 to 41.9 µg/m³ for PM(2.5). Fine particles constituted 77% of PM10, indicating that PM(2.5) made a significant contribution to indoor air quality at the hospital. PM1 ranged from 9.9 to 35.6 µg/m³, accounting for 93% of PM(2.5). PIXE identified 21 elements in PM, including health-hazardous metals (manganese, iron, copper, and vanadium) and carcinogenic elements (nickel, chromium, arsenic, and lead). However, no significant indoor source of PM emissions was identified, while outdoor air was the major contributor of indoor particles. Further, no significant risks existed through PM10 inhalation for population at the respective hospital.

2020 COVID-19 lockdown and the impacts on air quality with emphasis on urban, suburban and rural zones.

Air quality improvements pollution changes due to COVID-19 restrictions have been reported for many urban developments and large metropolitan areas, but the respective impacts at rural and remote zones are less frequently analysed. This study evaluated air pollution changes across all Portugal (68 stations) considering all urban, suburban and rural zones. PM10, PM2.5, NO2, SO2, ozone was analysed in pre-, during, and post-lockdown period (January-May 2020) and for a comparison also in 2019. NO2 was the most reduced pollutant in 2020, which coincided with decreased traffic. Significant drop (15-71%) of traffic related NO2 was observed specifically during lockdown period, being 55% for the largest and most populated region in country. PM was affected to a lesser degree (with substantial differences found for largely populated areas (Lisbon region ~ 30%; North region, up to 49%); during lockdown traffic-related PM dropped 10-70%. PM10 daily limit was exceeded 50% less in 2020, with 80% of exceedances before lockdown period. SO2 decreased by 35%, due to suspended industrial productions, whereas ozone concentrations slightly (though not significantly) increased (83 vs. 80 µg m-3).

Influence of traffic emissions on the carcinogenic polycyclic aromatic hydrocarbons in outdoor breathable particles.

Because polycyclic aromatic hydrocarbons (PAHs) have been proven to be toxic, mutagenic, and/or carcinogenic, there is widespread interest in analyzing and evaluating exposure to PAHs in atmospheric environments influenced by different emission sources. Because traffic emissions are one of the biggest sources of fine particles, more information on carcinogenic PAHs associated with fine particles needs to be provided. Aiming to further understand the impact of traffic particulate matter (PM) on human health, this study evaluated the influence of traffic on PM10 (PM with aerodynamic diameter < 10 microm) and PM2.5 (PM with aerodynamic diameter < 2.5 microm), considering their concentrations and compositions in carcinogenic PAHs. Samples were collected at one site influenced by traffic emissions and at one reference site using low-volume samplers. Analysis of PAHs was performed by microwave-assisted extraction combined with liquid chromatography (MAE-LC); 17 PAHs, including 9 carcinogenic ones, were quantified. At the site influenced by traffic emissions, PM10 and PM2.5 concentrations were, respectively, 380 and 390% higher than at the background site. When influenced by traffic emissions, the total concentration of nine carcinogenic compounds (naphthalene, chrysene, benzo(a)anthracene, benzo(b) fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, indeno(1,2,3-cd)pyrene, and dibenzo(a,l)pyrene) was increased by 2400 and 3000% in PM10 and PM2.5, respectively; these nine carcinogenic compounds represented 68 and 74% of total PAHs (sigma(PAHs)) for PM10 and PM2.5, respectively. All PAHs, including the carcinogenic compounds, were mainly present in fine particles. Considering the strong influence of these fine particles on human health, these conclusions are relevant for the development of strategies to protect public health.

Ultrafine particles: Levels in ambient air during outdoor sport activities.

Conducting aerobic activity on regular basis is recognised as one of the steps to maintain healthier lifestyle. The positive outcomes though can be outweighed if conducted in polluted atmosphere. Furthermore, the specific inhalation during exercising, which results in bypass of nasal filtration systems and deeper penetration into the respiratory system, might result in higher risks especially to pollutants such as ultrafine particles (UFP), which aerodynamic particle diameter are <100 nm. Thus, this work aims to evaluate UFP levels at sites used for conducting physical sport activities outdoors and to estimate the respective inhalation doses considering various scenarios and different physical activities. Monitoring of UFP was conducted during three weeks (May-June 2015) at four different sites (S1-S4) regularly used to conduct physical exercising. The results showed that UFP highly varied (medians 5.1-20.0 × 103 # cm-3) across the four sites, with the highest UFP obtained when exercising next to trafficked streets whereas S3 and S4 (a garden and city park) exhibited 2-4 times lower UFP. In view of the obtained UFP concentrations, the estimated inhalation doses ranged 1.73 × 108-3.81 × 108 # kg-1 when conducting moderately intense sport activities and 1.93 × 108-5.95 × 108 # kg-1 for highly intense ones. Highly intense activities (i.e. running) led to twice higher UFP exposure; children and youths (5-17 yrs old) experienced 203-267% higher doses. Considering the age- and gender- differences, estimated UFP doses of males were 1.1-2.8 times higher than of females. Finally, UFP inhalation doses estimated for walking (commuting to work and/or schools) were 1.6-7.5 times lower than when conducting sport activities. Thus to protect public health and to promote healthy and physically active lifestyle, strategies to minimize the negative impacts of air pollution should be developed and implemented.

Assessment of indoor air exposure among newborns and their mothers: Levels and sources of PM10, PM2.5 and ultrafine particles at 65 home environments.

Significant efforts have been directed towards addressing the adverse health effects of atmospheric particles, emphasizing the relevance of indoor exposure. Homes represent an indoor environment where human spend the majority of their time. Thus, the objective of this work was to concurrently assess different matrix of indoor particles considering both mass (PM10, PM2.5) and number (N20-1000) concentrations in indoor and outdoor air of homes (n = 65). Real-time measurements (PM10, PM2.5, UFP) were conducted simultaneously during 48 h in dwellings situated in Oporto, Portugal. In 75% of homes, indoor PM2.5 (mean = 53 µg m-3) exceeded limit of 25 µg m-3, for PM10 (mean = 57 µg m-3) 41% of homes demonstrated average levels higher than 50 µg m-3, thus indicating potential risks. Indoor PM10 was mostly (82-99%) composed of PM2.5, both PM were highly correlated (|rs|>0.9655), thus suggesting the similar origin. Indoor PM originated from infiltrations of outdoor emissions; ∼70% of homes exhibited indoor to outdoor (I/O) ratio < 1. On the contrary, UFP indoors (mean = 13.3 × 103 # cm-3) were higher than outdoors (mean = 10.0 × 103 # cm-3). Indoor UFP spatially varied as follows: kitchens > living rooms > bedrooms. UFP indoors were poorly correlated (|rs| = 0.456) with outdoor concentrations, I/O ratios showed that indoor UFP predominantly originated from indoor emission sources (combustions). Therefore, in order to reduce exposure to UFP and protect public health, the primary concerns should be focused on controlling emissions from indoor sources.

Assessment of indoor air exposure at residential homes: Inhalation dose and lung deposition of PM10, PM2.5 and ultrafine particles among newborn children and their mothers.

Accurate assessment of particulate matter (PM) dose and respiratory deposition is essential to better understand the risks of exposure to PM and, consequently, to develop the respective risk-control strategies. In homes, this is especially relevant in regards to ultrafine particles (UFP; <0.1 µm) which origin in these environments is mostly due to indoor sources. Thus, this study aimed to estimate inhalation doses for different PM mass/number size fractions (i.e., PM10, PM2.5 and UFP) in indoor air of residential homes and to quantify the deposition (total, regional and lobar) in human respiratory tract for both newborn children and mothers. Indoor real-time measurements of PM10, PM2.5 and UFP were conducted in 65 residential homes situated in Oporto metropolitan area (Portugal). Inhalation doses were estimated based on the physical characteristics of individual subjects and their activity patterns. The multi-path particle dosimetry model was used to quantify age-specific depositions in human respiratory tract. The results showed that 3-month old infants exhibited 4-fold higher inhalation doses than their mothers. PM10 were primarily deposited in the head region (87%), while PM2.5 and UFP depositions mainly occurred in the pulmonary area (39% and 43%, respectively). Subject age affected the pulmonary region and the total lung deposition; higher deposition being observed among the newborns. Similarly, lower lobes (left lobe: 37% and right lobe: 30%) received higher PM deposition than upper and middle lobes; right lobes lung are prone to be more susceptible to respiratory problems, since asymmetric deposition was observed. Considering that PM-related diseases occur at specific sites of respiratory system, quantification of site-specific particle deposition should be predicted in order to better evidence the respective health outcomes resulting from inhaled PM.

Firefighters exposure to fire emissions: Impact on levels of biomarkers of exposure to polycyclic aromatic hydrocarbons and genotoxic/oxidative-effects.

Firefighters represent one of the riskiest occupations, yet due to the logistic reasons, the respective exposure assessment is one of the most challenging. Thus, this work assessed the impact of firefighting activities on levels of urinary monohydroxyl-polycyclic aromatic hydrocarbons (OHPAHs; 1-hydroxynaphthalene, 1-hydroxyacenaphthene, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 1-hydroxypyrene, 3-hydroxybenzo(a)pyrene) and genotoxic/oxidative-effect biomarkers (basal DNA and oxidative DNA damage) of firefighters from eight firehouses. Cardiac frequency, blood pressure and arterial oxygen saturation were also monitored. OHPAHs were determined by liquid-chromatography with fluorescence detection, while genotoxic/oxidative-effect biomarkers were assessed by the comet assay. Concentrations of total OHPAHs were up to 340% higher (p ≤ 0.05) in (non-smoking and smoking) exposed workers than in control subjects (non-smoking and non-exposed to combat activities); the highest increments were observed for 1-hydroxynaphthalene and 1-hydroxyacenaphthene (82-88% of ∑OHPAHs), and for 2-hydroxyfluorene (5-15%). Levels of biomarker for oxidative stress were increased in non-smoking exposed workers than in control group (316%; p ≤ 0.001); inconclusive results were found for DNA damage. Positive correlations were found between the cardiac frequency, ∑OHPAHs and the oxidative DNA damage of non-smoking (non-exposed and exposed) firefighters. Evidences were raised regarding the simultaneous use of these biomarkers for the surveillance of firefighters' health and to better estimate the potential short-term health risks.

Analysis of polycyclic aromatic hydrocarbons in atmospheric particulate samples by microwave-assisted extraction and liquid chromatography.

A methodology based on microwave-assisted extraction (MAE) and LC with fluorescence detection (FLD) was investigated for the efficient determination of 15 polycyclic aromatic hydrocarbons (PAHs) regarded as priority pollutants by the US Environmental Protection Agency and dibenzo(a,l)pyrene in atmospheric particulate samples. PAHs were successfully extracted from real outdoor particulate matter (PM) samples with recoveries ranging from 81.4 +/- 8.8 to 112.0 +/- 1.1%, for all the compounds except for naphthalene (62.3 +/- 18.0%) and anthracene (67.3 +/- 5.7%), under the optimum MAE conditions (30.0 mL of ACN for 20 min at 110 degrees C). No clean-up steps were necessary prior to LC analysis. LOQs ranging from 0.0054 ng/m(3 )for benzo(a)anthracene to 0.089 ng/m(3) for naphthalene were reached. The validated MAE methodology was applied to the determination of PAHs from a set of real world PM samples collected in Oporto (north of Portugal). The sum of particulate-bound PAHs in outdoor PM ranged from 2.5 and 28 ng/m(3).

Assessment of ultrafine particles in primary schools: Emphasis on different indoor microenvironments.

Due to the negative health impacts, significant efforts have been directed towards investigating ultrafine particle (UFP) exposure in various indoor environments. As children spend approximately one third of their time in schools, educatory environments deserve particular attention; however, majority of past research has focused on UFP assessment in classrooms. Thus, this work aims to expand the characterization of UFP in primary schools by considering different indoor and outdoor school microenvironments and estimating inhalation doses for the respective students (6-11yrs old). Real-time UFP measurements were daily conducted (9:00-17:30) in 20 primary schools in Oporto (January-April 2014; October-February 2015) in classrooms, canteens, gyms, libraries, and concurrently outdoors. Overall, UFP concentrations showed large temporal and spatial variations. For classrooms (n = 73), median UFP (1.56 × 103-16.8 × 103 # cm-3) were lower than the corresponding levels in ambient air of schools (1.79 × 103-24.1 × 103 # cm-3). Outdoor emissions contributed to indoor UFP (indoor-to-outdoor ratios I/O of 0.0.30-0.85), but ventilation, room characteristics and its occupancy were identified as important parameters contributing to overall indoor UFP levels. Considering specific indoor school microenvironments, canteens were the microenvironment with the highest UFP levels (5.47 × 103-36.4 × 103 # cm-3), cooking conducted directly on school grounds resulted in significantly elevated UFP in the respective classrooms (p < 0.05); the lowest UFP were found in libraries (4.45 × 103-8.50 × 103 # cm-3) mostly due to the limited occupancies. Although students spend majority of their school time in classrooms (66-71%), classroom exposure was not consistently the predominant contributor to school total UFP inhalation dose (29-75%). Outdoor exposure contributed 23-70% of school dose (depending on UFP levels in ambient levels and/or conducted activities) whereas short periods of lunch break accounted for 8-40%. Therefore, when evaluating UFP exposure in educatory settings other microenvironments beyond classrooms should be an integral part of the study.