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.

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.

Epidemiological Impact of Neurodegenerative Diseases in the Rural Spanish-Portuguese Cross-Border Region.

INTRODUCTION: Epidemiological data indicate that neurodegenerative diseases show a high prevalence with a progressive increasing trend, especially in aging populations, as is the case in rural areas. The objective of this study was to assess the quantitative impact of neurodegenerative diseases in rural areas of the Spanish-Portuguese border region and to describe the epidemiological profile of the most prevalent disorders in one of the most depopulated and aged regions of Europe. METHODS: A cross-sectional descriptive study was designed to estimate the prevalence of subjects diagnosed with the most common neurodegenerative disorders: dementia (Alzheimer's disease and other dementias), Parkinson's disease and Parkinsonism, and multiple sclerosis in the Spanish-Portuguese cross-border border region in 2020. It includes Bragança and Guarda Districts (Portugal) and Salamanca (Castilla y León, Spain). RESULTS: Neurodegenerative diseases accounted for 1.85% in the Spanish-Portuguese cross-border region in 2020; a total of 5,819 records were reported: 987 (prevalence, 2.51%) in Salamanca (Spain); 2,332 (prevalence, 1.87%) in Bragança; and 2,500 (prevalence, 1.66%) in Guarda. Female population suffered from them in higher proportion (2.35 vs. 1.32%). Dementia represented 1.19% (3,744), Parkinson's disease and Parkinsonism 0.58% (1,823), and multiple sclerosis 0.08% (252). These disorders impacted older age groups. In the rural border region of Spain, 1 out of 4 cases were institutionalized. CONCLUSION: The findings reveal the health impact of neurodegenerative diseases in the Spanish-Portuguese cross-border region. The epidemiological data emphasize the region's circumstances and highlight research priorities. Intervention strategies must be implemented in the region to ensure quality healthcare in rural areas.

Exploring Clinical Trials to Manage Firefighters' Sleep Quality: A PRISMA Compliant Systematic Review.

Sleep research has grown over the past decades and investigators are deeply involved in studying sleep and its impact on human health and body regulation. Despite the understanding that insufficient sleep is strongly linked to the development of several disorders, unsatisfactory sleep exposes health and safety to innumerous risks. The present study aims to review and analyze the main results of clinical trials, registered at ClinicalTrials.gov and ICTRT databases, and developed construct strategies to improve sleep quality on firefighters and enhance professionals' sleep and health conditions. The protocol was registered in PROSPERO under number CRD42022334719. Trials registered between first registry and 2022 were included. We retrieved 11 registered clinical trials; seven met eligibility criteria and were included in the review. A relation between sleep disorders, shift work, and occupational health problems was found, and retrieved trials showed that sleep education programs can improve sleep quality and sleep hygiene. Science has already recognized sleep's importance for metabolic functioning and survivorship. Nevertheless, it continues to play a major role in discovering methods to diminish the problems faced. Strategies contemplating sleep education, or intervention, should be presented to fire services to tackle this problem and promote healthier and safer environments.

Conhecimento sobre suporte básico de vida em estudantes do ensino superior de ciências da saúde / Knowledge about basic life support in higher education health students / Conocimientos sobre el soporte vital básico en los estudiantes de ciencias de la salud de la enseñanza superior

Resumo Enquadramento: A paragem cardiorrespiratória constitui um grave problema que prossupõe uma atuação imediata de terceiros, devendo-se para tal recorrer ao suporte básico de vida (SBV). Objetivo: Avaliar os conhecimentos em SBV, em estudantes do ensino superior da área da saúde, e analisar as associações entre o nível de conhecimento e variáveis sociodemográficas, académicas e de contexto socioeducativo. Metodologia: Estudo correlacional, transversal, quantitativo, efetuado numa amostra de estudantes do ensino superior. Resultados: Obteve-se uma amostra de 683 estudantes, em média com 21 anos de idade e maioritariamente do sexo feminino. A pontuação média dos conhecimentos foi de 11,79 pontos, numa escala de 0 a 20. O nível de conhecimentos está relacionado de forma estatisticamente significativa, com a licenciatura e o ano de curso frequentado, com o terem frequentado um curso/formação em SBV, com a frequência de unidades curriculares onde se abordaram conteúdos de SBV. Conclusão: As pontuações médias obtidas enquadram-se num nível suficiente, destacando-se com pontuações mais elevadas os seguintes grupos: estudantes de 4º ano; curso de enfermagem; formação prévia em SBV.

Abstract Background: Cardiac arrest (CA) is a serious problem that requires the immediate intervention of third parties using basic life support (BLS). Objectives: To assess higher education health students' knowledge about BLS and analyze the associations between level of knowledge and sociodemographic, academic, and socio-educational variables. Methodology: Quantitative correlational cross-sectional study in a sample of higher education students. Results: The sample consisted of 683 students, with a mean age of 21 years, mostly women. The mean knowledge score was 11.79 points, on a scale of 0 to 20. There was a statistically significant association between the level of knowledge and the program, the year of study, having attended a BLS course/training, and having attended course units with BLS content. Conclusion: The mean scores reflect a sufficient level of knowledge, with the following groups obtaining higher scores: 4th-year students, nursing program, and previous BLS training.

Resumen Marco contextual: La parada cardiorrespiratoria es un problema grave que requiere la intervención inmediata de terceros, para lo cual debemos recurrir al soporte vital básico (SBV). Objetivo: Evaluar los conocimientos sobre el SVB en los estudiantes del área de la salud de la enseñanza superior y analizar las asociaciones entre el nivel de conocimiento y las variables sociodemográficas, académicas y del contexto socioeducativo. Metodología: Estudio correlacional, transversal y cuantitativo, realizado sobre una muestra de estudiantes de enseñanza superior. Resultados: Se obtuvo una muestra de 683 estudiantes, con una edad media de 21 años y mayoritariamente del sexo femenino. La puntuación media de los conocimientos fue de 11,79 puntos en una escala de 0 a 20. El nivel de conocimiento está relacionado de forma estadísticamente significativa con la titulación de grado y el año del curso realizado, con haber asistido a un curso/formación en SVB y con la frecuencia de las unidades curriculares en las que se abordaron contenidos de SVB. Conclusión: Las puntuaciones medias obtenidas están dentro de un nivel suficiente, y destacan con puntuaciones más altas los siguientes grupos: estudiantes de 4.º curso; grado de enfermería; formación previa en SBV.

(In)satisfação com a imagem corporal e atitudes alimentares em estudantes do ensino secundário / (Dis)satisfaction with corporal image and alimentary attitudes in high school students / (In)satisfacción con la imagen corporal y actitudes alimentarias en estudiantes de la enseñanza secundaria

CONTEXTO: A autoimagem é um conceito transversal a toda humanidade, muito ligada à identidade pessoal. A preocupação permanente com a imagem corporal, leva a que os jovens procurem alcançar a aparência física perfeita, podendo adotar atitudes alimentares disfuncionais, com implicações na sua saúde. OBJETIVOS: Avaliar as atitudes alimentares e a satisfação com a imagem corporal em estudantes do ensino secundário. MÉTODOS: Estudo observacional, analítico e transversal. Foram avaliados 184 alunos aos quais foi aplicado um questionário que incluía o Questionário de Silhuetas de Collins e a escala Children's Eating Attitude Test validada para a população Portuguesa. Os dados foram tratados recorrendo-se ao programa SPSS, versão 22.0. RESULTADOS: Verificou-se que todas as dimensões da Children's Eating Attitude Test apresentavam valores médios baixos traduzindo-se em comportamentos alimentares normais. A aplicação do Questionário de Silhuetas de Collins revelou que 38% dos adolescentes estava satisfeito com a sua imagem corporal. Os resultados da escala de Children's Eating Attitude Test em função da satisfação com a imagem corporal indicam que as atitudes alimentares são estatisticamente distintas entre os jovens satisfeitos e não satisfeitos com a silhueta, especificamente nas dimensões cumprimento da dieta (p=0,004) e controlo da ingestão alimentar (p=0,033). CONCLUSÕES: Os resultados obtidos revelam a predominância de insatisfação com a imagem corporal dos jovens, assim como a existência de relação entre as atitudes alimentares e a satisfação corporal. Realça-se a necessidade de implementar estratégias multidisciplinares, não apenas direcionadas aos jovens, mas alargadas à dinâmica familiar.

BACKGROUND: Self-image is a transversal concept to all humanity, closely related to personal identity. The ongoing concern with self-image causes young people to try to reach the perfect physical appearance, and they may adopt dysfunctional alimentary attitudes with effects on their health. AIM: To evaluate the alimentary attitudes and satisfaction with corporal image in high school students. METHODS: Observational, analytic and transversal study. 184 students were evaluated through an application form that included the Collins and the Children's Eating Attitude Test scale validated for Portuguese population. The data was treated using the SPSS programme, 2.0 version. RESULTS:It was verified that all Children's Eating Attitude Test scale dimension presented low medium value translated in normal nutritional habits. The application of the Collins Questionnaire has revealed that 38% of the teenagers was satisfied with their body image. The results from the Children's Eating Attitude Test s scale according to the satisfaction with body image indicate that alimentary attitudes statistically different between the satisfied and non-satisfied young with their silhouette, specifically in the dimensions of diet compliance (p=0,004) and dietary intake control (p=0,033). CONCLUSIONS: The obtained results reveal the predominance of dissatisfaction with body image of young people, as well as the existence of a relation between the alimentary attitudes and corporal satisfaction. It is necessary to implementmultidisciplinary strategies, not only directed to the young, but also the family dynamic.

CONTEXTO: La autoimagen es un concepto transversal a toda la humanidad, muy ligada a la identidad personal. La preocupación permanente con la imagen corporal, lleva a que los jóvenes procuren alcanzar la apariencia física perfecta, pudiendo adoptar actitudes alimentarias disfuncionales, con implicaciones en su salud. OBJETIVOS: Evaluar las actitudes alimenticias y la satisfacción con la imagen corporal en estudiantes de enseñanza secundaria. METODOLOGÍA: Estudio observacional, analítico y transversal. Se evaluaron 184 estudiantes quienes se les aplicó un formulario que incluía el Cuestionario Siluetas Collins y la escala Children's Eating Attitude Test validado para la población portuguesa. Los datos fueron tratados utilizando el programa SPSS, versión 22.0. RESULTADOS: Se verificó que todas las dimensiones de la Children's Eating Attitude Test scale presentaban valores medios bajos, traduciéndose en comportamientos alimentarios normales. La aplicación del Cuestionario de Siluetas de Collins reveló que 38% de los adolescentes estaba satisfecho con su imagen corporal. Los resultados de la escala de Children's Eating Attitude Test scale en función de la satisfacción con la imagen corporal indican que las actitudes alimenticias son estadísticamente distintas entre los jóvenes satisfechos y no satisfechos con la silueta, específicamente en las dimensiones cumplimiento de la dieta (p = 0,004) y control de la ingesta alimentaria (p = 0,004) p = 0,033). CONCLUSIONES: Los resultados obtenidos revelan la predominancia de insatisfacción con la imagen corporal de los jóvenes, así como la existencia de relación entre las actitudes alimenticias y la satisfacción corporal. Se destaca la necesidad de implementar estrategias multidisciplinares, no sólo dirigidas a los jóvenes, sino que se amplían a la dinámica familiar.

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.

Wood smoke exposure of Portuguese wildland firefighters: DNA and oxidative damage evaluation.

Portugal is among the European Union countries most devastated by forest fires each year. In the last three decades, more than 3.8 million hectares of forest were burned. Wildland firefighters are exposed to a variety of hazards, including many toxic combustion products that may lead to deleterious health effects. Epidemiological studies showed a positive association between firefighting and several chronic diseases, including cancer. Results from biomonitoring studies in firefighters, particularly concerning genotoxicity evaluation, constitute a valuable tool for investigating important occupational hazards. Thus, the aim of this study was to assess genotoxicity in a group of wildland firefighters using the comet assay for DNA damage and oxidative stress. Both parameters were increased in firefighters compared to controls, but significance was only found for basal DNA damage. No significant influence was found regarding major confounding variables on the genotoxic endpoints studied, with the exception of age. Data obtained provide preliminary information on human health effects of wildland firefighting exposure at genetic and molecular levels. These findings may also provide new important data to serve as public awareness to the potential adverse health risks involving wildland firefighting. Implementation of security and hygiene measures in this sector as well as good practices campaigns may be crucial to decrease risk.

Individual and cumulative impacts of fire emissions and tobacco consumption on wildland firefighters' total exposure to polycyclic aromatic hydrocarbons.

There is limited information about wildland firefighters' exposure to polycyclic aromatic hydrocarbons (PAHs), being scarce studies that included the impact of tobacco consumption. Thus, this work evaluated the individual and cumulative impacts of firefighting activities and smoking on wildland firefighters' total exposure to PAHs. Six urinary PAH metabolites (1-hydroxynaphthalene (1OHNaph), 1-hydroxyacenaphthene (1OHAce), 2-hydroxyfluorene (2OHFlu), 1-hydroxyphenanthrene (1OHPhen), 1-hydroxypyrene (1OHPy), and 3-hydroxybenzo[a]pyrene (3OHB[a]P)) were quantified by high-performance liquid chromatography with fluorescence detection. Firefighters from three fire stations were characterized and organized in three groups: non-smoking and non-exposed to fire emissions (NSNExp), smoking non-exposed (SNExp), and smoking exposed (SExp) individuals. 1OHNaph+1OHAce were the most predominant OH-PAHs (66-91% ∑OH-PAHs), followed by 2OHFlu (2.8-28%), 1OHPhen (1.3-7%), and 1OHPy (1.4-6%). 3OHB[a]P, the carcinogenicity PAH biomarker, was not detected. Regular consumption of tobacco increased 76-412% ∑OH-PAHs. Fire combat activities promoted significant increments of 158-551% ∑OH-PAHs. 2OHFlu was the most affected compound by firefighting activities (111-1068%), while 1OHNaph+1OHAce presented the more pronounced increments due to tobacco consumption (22-339%); 1OHPhen (76-176%) and 1OHPy (20-220%) were the least influenced ones. OH-PAH levels of SExp firefighters were significantly higher than in other groups, suggesting that these subjects may be more vulnerable to develop and/or aggravate diseases related with PAHs exposure.

Occupational exposure of firefighters to polycyclic aromatic hydrocarbons in non-fire work environments.

This work aims to characterize personal exposure of firefighters to polycyclic aromatic hydrocarbons (PAHs) in non-fire work environments (fire stations), and assesses the respective risks. Eighteen PAHs (16 considered by USEPA as priority pollutants, dibenzo[a,l]pyrene and benzo[j]fluoranthene) were monitored in breathing zones of workers at five Portuguese fire stations during a normal shift. The obtained levels of PAHs fulfilled all existent occupational exposure limits as well as air quality guidelines with total concentrations (ΣPAHs) in range of 46.8-155ngm-3. Light compounds (2-3 rings) were the most predominant congeners (74-96% of ΣPAHs) whereas PAHs with 5-6 rings accounted 3-9% of ΣPAHs. Fuel and biomass combustions, vehicular traffic emissions, and use of lubricant oils were identified as the main sources of PAHs exposure at the studied fire corporations. Incremental lifetime cancer risks were below the recommend USEPA guideline of 10-6 and thus negligible for all the studied subjects, but WHO health-based guideline level of 10-5 was exceeded (9-44 times) at all fire corporations. These results thus show that even during non-fire situations firefighters are exposed to PAHs at levels that may promote some adverse health outcomes; therefore the respective occupational exposures to these compounds should be carefully controlled.

Polycyclic aromatic hydrocarbons at fire stations: firefighters' exposure monitoring and biomonitoring, and assessment of the contribution to total internal dose.

This work characterizes levels of eighteen polycyclic aromatic hydrocarbons (PAHs) in the breathing air zone of firefighters during their regular work shift at eight Portuguese fire stations, and the firefighters' total internal dose by six urinary monohydroxyl metabolites (OH-PAHs). Total PAHs (ΣPAHs) concentrations varied widely (46.4-428ng/m3), mainly due to site specificity (urban/rural) and characteristics (age and layout) of buildings. Airborne PAHs with 2-3 rings were the most abundant (63.9-95.7% ΣPAHs). Similarly, urinary 1-hydroxynaphthalene and 1-hydroxyacenaphthene were the predominant metabolites (66-96% ΣOH-PAHs). Naphthalene contributed the most to carcinogenic ΣPAHs (39.4-78.1%) in majority of firehouses; benzo[a]pyrene, the marker of carcinogenic PAHs, accounted with 1.5-10%. Statistically positive significant correlations (r≥0.733, p≤0.025) were observed between ΣPAHs and urinary ΣOH-PAHs for firefighters of four fire stations suggesting that, at these sites, indoor air was their major exposure source of PAHs. Firefighter's personal exposure to PAHs at Portuguese fire stations were well below the existent occupational exposure limits. Also, the quantified concentrations of post-shift urinary 1-hydroxypyrene in all firefighters were clearly lower than the benchmark level (0.5µmol/mol) recommended by the American Conference of Governmental Industrial Hygienists.

Firefighters' exposure biomonitoring: Impact of firefighting activities on levels of urinary monohydroxyl metabolites.

The concentrations of six urinary monohydroxyl metabolites (OH-PAHs) of polycyclic aromatic hydrocarbons, namely 1-hydroxynaphthalene, 1-hydroxyacenaphthene, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 1-hydroxypyrene (1OHPy), and 3-hydroxybenzo[a]pyrene, were assessed in the post-shift urine of wildland firefighters involved in fire combat activities at six Portuguese fire corporations, and compared with those of non-exposed subjects. Overall, median levels of urinary individual and total OH-PAHs (ΣOH-PAHs) suggest an increased exposure to polycyclic aromatic hydrocarbons during firefighting activities with ΣOH-PAH levels in exposed firefighters 1.7-35 times higher than in non-exposed ones. Urinary 1-hydroxynaphthalene and/or 1-hydroxyacenapthene were the predominant compounds, representing 63-98% of ΣOH-PAHs, followed by 2-hydroxyfluorene (1-17%), 1-hydroxyphenanthrene (1-13%), and 1OHPy (0.3-10%). A similar profile was observed when gender discrimination was considered. Participation in fire combat activities promoted an increase of the distribution percentage of 1-hydroxynaphthalene and 1-hydroxyacenaphthene, while contributions of 1-hydroxyphenanthrene and 1OHPy decreased. The detected urinary 1OHPy concentrations (1.73×10-2 to 0.152µmol/mol creatinine in exposed subjects versus 1.21×10-2 to 5.44×10-2µmol/mol creatinine in non-exposed individuals) were lower than the benchmark level (0.5µmol/mol creatinine) proposed by the American Conference of Governmental Industrial Hygienists. This compound, considered the biomarker of exposure to PAHs, was the less abundant one from the six analyzed biomarkers. Thus the inclusion of other metabolites, in addition to 1OHPy, in future studies is suggested to better estimate firefighters' occupational exposure to PAHs. Moreover, strong to moderate Spearman correlations were observed between individual compounds and ΣOH-PAHs corroborating the prevalence of an emission source.