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Introduction: Rapid urbanisation over the past century has led to increased traffic density and higher levels of ambient air pollutants. We aimed to investigate whether the prevalence of respiratory symptoms, asthma, and chronic bronchitis increases with the level of self-reported exposure to traffic and occupational-related pollution.

Material and methods: The study population comprised 25,889 general population subjects ages 16–75 years participating in the Swedish part of the GA2LEN study. Data were collected in the cities of Umeå, Uppsala, Stockholm, and Gothenburg. Self-reported data on disturbance of fumes from traffic in the residential area or occupational exposure to gas, dust, or smoke, as well as on patient demographics, respiratory symptoms, asthma and chronic bronchitis, were obtained from questionnaires.

Results: The prevalence of respiratory symptoms, asthma, and chronic bronchitis was higher both among participants reporting traffic-related exposure and those with a history of occupational exposure to fumes, smoke, and dust than among those unexposed; (wheeze 27 vs 13%), nocturnal cough (35 vs 22%), asthma (11 vs 6%) and chronic bronchitis (22 vs 8%); all p < 0.0001. When combining traffic and occupational exposure, the highest prevalence was found amongst those exposed to both. Associations with occupational exposure were generally stronger in women, and those with traffic exposure were stronger in men.

Conclusion: In this large population-based sample, self-reported residential traffic exposure and occupational exposure to dust, fumes, or smoke were associated with increased prevalence of respiratory symptoms, asthma, and chronic bronchitis. Although causality cannot be inferred, these findings underscore the importance of assessing environmental and occupational exposures in evaluating respiratory health.

Indoor dampness and mould exposure are associated with respiratory health, but there is limited evidence on long-term effects in adults. Indoor dampness and mould, and the onset of respiratory symptoms, asthma, and rhinitis, were studied in the Respiratory Health in Northern Europe (RHINE) cohort, in which 8407 adults participated in both the 20-year and 30-year follow-up (RHINE III and IV, respectively). Participants completed a questionnaire on indoor dampness and mould at home and at the workplace, and on respiratory health. In RHINE IV, the prevalence of dampness or mould exposure in the past 10 years was 28.6%, while 15.1% of participants reported a 20-year cumulative exposure. Home exposure of dampness or mould was linked to increased onset of nocturnal chest tightness (OR = 1.80), nocturnal breathlessness (OR = 1.76), productive cough (OR = 1.41), and allergic rhinitis (OR = 1.27) and work exposure of dampness or mould with increased onset of wheeze (OR = 1.58), nocturnal chest tightness (OR = 1.53), doctor-diagnosed asthma (OR = 1.68), and rhinitis (OR = 1.35). Combined home and work exposure showed stronger associations for nocturnal chest tightness (OR = 1.99), doctor-diagnosed asthma (OR = 1.90), and rhinitis (OR = 2.24). Cumulative 20-year exposure accentuated the association with respiratory symptoms. Long-term exposure to dampness or mould at home or at work increased the risk of developing respiratory symptoms, asthma, and rhinitis. Combined exposure at home and work, and a prolonged exposure period, may play a significant role in the development of adverse respiratory outcomes in adults.

The transition toward a circular economy is driving rapid growth in the recycling sector, yet occupational exposure remains poorly characterized, including exposure to phthalates and bisphenols. We conducted a human biomonitoring study among recycling workers handling e-waste, metal waste, and mixed waste in Sweden. The study included 114 exposed workers, 23 low-exposed workers, and 18 controls. Pre- and post-shift urine samples were analysed for phthalate and bisphenol metabolites using LC–MS/MS. Workers showed significantly higher post-shift urinary concentrations of phthalates (DiBP, DnBP, BBzP, and DnHP) and bisphenols (BPA and BPF) than controls; however, concentrations were generally lower in post-shift than in pre-shift samples across all exposure groups. Higher concentrations were observed among workers handling e-waste and metal waste, and among those performing extraction and, to a lesser extent, sorting and maintenance. Evidence of work-related exposure was observed for restricted legacy compounds (DEHP, DiBP, DnBP, BBzP, BPA) and newer or less-regulated substitutes (DPHP, DnHP, BPF). Correlation analyses indicated simultaneous co-exposure to multiple phthalates and bisphenols, and weak to moderate correlations with workplace dust concentrations (up to rS = 0.40) suggested that inhalation may partly contribute to exposure. Inadequate local exhaust ventilation was associated with higher urinary concentrations of most biomarkers and significantly higher BBzP levels. These findings highlight the complex chemical mixtures present in recycling environments and underscore the need to control emissions at the source and to continue monitoring regulated and emerging phthalates and bisphenols to support prevention strategies for a growing recycling workforce.

The green transition relies on metals, requiring increased metal recovery from waste. However, exposure risks among metal recycling workers are poorly understood. We conducted a cross-sectional study to assess dust and metal exposure among 139 recycling workers from 13 Swedish metal recycling companies and 90 controls. We documented work practices through observations and questionnaires and assessed dust and metal exposures using a combination of individual air sampling (inhalable (ID) and respirable dust) and biomonitoring (blood and pre-/post-shift urine). ICP-MS was used to measure 39 metals in air, 47 in blood, and 42 in urine. Thirty-two % of the workers were involved in the recycling of e-waste. At most workplaces, dust control was insufficient, respiratory protective equipment was rarely or incorrectly used, and hygienic routines were inadequate. This was reflected in 6.2 times higher ID levels in recycling workers; 14 % exceeded the 5 mg/m3 exposure limit for ID, and some also exceeded limits for Pb, Cu, As, Cd, and Sb. Workers had elevated blood and/or urine levels of Pb, Hg, Al, Sb, Fe and Mn with known human toxicity, and of Y, Lu, In, Ga, W, and Te with limited or unknown toxicity. Furthermore, observed were also co-exposure patterns for those metals. Inhalation was the likely primary exposure route for Pb, Sb, Y, In, and Te. In conclusion, Swedish recycling workers were exposed to elevated levels of dust and metals, highlighting the need for ongoing monitoring of both known and emerging metals.

Background: Air pollution and greenness are important determinants of population health. Understanding their long-term impacts can inform integrated urban and environmental policies to reduce mortality and improve health.

Objectives: To quantify both the real-world and potential impacts of two decades of changes in air pollution and greenness on all-cause mortality among adults aged 18-65 years in seven Northern European cities.

Methods: We conducted a health impact assessment using cohort-derived exposure distributions from 16,404 adults in the Respiratory Health in Northern Europe (RHINE) study. Annual exposures to particulate matter (PM2.5, PM10), nitrogen dioxide (NO2), and greenness (Normalized Difference Vegetation Index, NDVI) were estimated at residential addresses for 1990–2010. Exposure changes were linked to all-cause mortality using established exposure–response functions to estimate population attributable fractions (PAFs). Additional analyses estimated potential health benefits under the 2021 WHO Air Quality Guidelines (AQGs) and enhanced greenness scenarios.

Results: Between 1990 and 2010, exposures decreased on average by 3.0 μg/m3 for PM2.5, 4.4 μg/m3 for PM10, and 2.3 μg/m3 for NO2, while NDVI increased by 0.11. These changes corresponded to estimated PAF of 2.15% (95% CI: 1.83%–2.47%) for PM2.5, 2.53% (95% CI: 2.35%–2.72%) for PM10, 0.46% (95% CI: 0.41%–0.51%) for NO2, and 2.07% (95% CI: 1.88%–2.25%) for NDVI, representing the proportion of premature deaths prevented or delayed. Under counterfactual scenarios, alignment with the WHO AQGs would correspond to PAFs of 3.01% (95% CI: 2.58%–3.42%) for PM2.5, 1.56% (95% CI: 1.43%–1.69%) for PM10, and 1.59% (95% CI: 1.41%–1.77%) for NO2, while increasing greenness to the 75th percentile would correspond to 6.44% (95% CI: 5.74%–7.16%).

Conclusion: Real-world environmental improvements were estimated to prevent or delay a measurable proportion of all-cause deaths among working-age adults. Larger benefits could be achieved under more ambitious air quality and urban greening targets. These findings support integrated environmental policies to enhance public health.

Background: Evidence suggests that a father’s smoking in puberty may adversely impact respiratory health in offspring, possibly through epigenetic changes in germ cells. This study investigates whether snus use starting in or after puberty influences respiratory health in future offspring.

Methods: We analysed Swedish data from RHINE (Respiratory Health in Northern Europe) parents and RHINESSA (Respiratory Health in Northern Europe, Spain and Australia) offspring by using mixed-effect logistic regression to assess the links between paternal snus initiation around puberty and offspring asthma, chronic bronchitis, rhinitis, and eczema, adjusting for paternal and offspring smoking.

Results: We identified 1090 offspring–father pairs. The offspring’s median age was 29 years (17–51) and 55% were women. The maternal line (n = 1421) was not analysed, as <1% of mothers used snus in puberty. The offspring of fathers starting snus use in puberty (n = 89) had a higher risk of current allergic asthma [odds ratio (OR) 1.42; 95% confidence interval (CI) 1.02–1.97], at least three asthma symptoms with allergy (OR 1.13; 95% CI 1.10–1.21), chronic bronchitis (OR 2.17; 95% CI 1.04–4.54), and eczema (OR 1.45; 95% CI 1.27–1.65). Fathers’ snus use starting after puberty (n = 252) showed no consistent associations with offspring outcomes. The effect estimates were consistent after excluding offspring using snus in puberty.

Conclusion: Paternal snus use starting in puberty was associated with a higher risk of asthma and other respiratory and allergic symptoms in offspring. These findings support the hypothesis that exposures in puberty may impact future generations’ respiratory health, possibly through epigenetic changes. This highlights the need for research on exposures during this period and actions to prevent habits that could negatively impact future offspring’s health.

Background Personalised medicine targets treatable traits with tailored therapy. Extrapulmonary traits, modifiable and related to asthma, were analysed for their association with hospitalisation rates.

Methods We conducted an observational study of a general population cohort in Sweden, based on the Respiratory Health in Northern Europe (RHINE) and Global Allergy and Asthma European Network (GA2LEN) studies. Participants completed questionnaires in 2008–2010, including respiratory symptoms, smoking habits and education level. Data were linked with national health registers to obtain information on hospitalisations with asthma.

Results Of 31 000 participants, 2341 had current asthma. Asthma patients exhibited a higher prevalence of airway comorbidities, such as rhinitis, allergic rhinitis and chronic rhinosinusitis, which were associated with increased hospitalisation rates. Obesity, insomnia and snoring were also significant risk factors for hospitalisation. A clear trend of increasing hospitalisations was observed with a higher number of treatable traits, especially in asthma patients aged <60 years, who had significantly increased odds of hospitalisation when presenting with three or more traits (adjusted OR 1.88, 95% CI 1.03–3.42). Chronic rhinosinusitis contributed the most to hospitalisations (10.7% population attributable fraction), followed by obesity (8.6% population attributable fraction). On average, each increase in number of treatable traits was associated with a 13% increased risk of hospitalisation (HR 1.13, 95% CI 1.02–1.25, p=0.02). Smoking and damp/ mould exposure had a negligible contribution to the overall burden of hospitalisations with asthma.

Conclusion Recognising extrapulmonary traits like obesity and chronic rhinosinusitis is vital in asthma management, as they increase the risk of future hospitalisations.

The European Union (EU) Ambient Air Quality Directive (AAQD) and Drinking Water Directive (DWD) are aimed at maintaining and improving air quality and ensuring high standards for potable water across the EU. Besides several other indicators, the AAQD and DWD consist of chemical parameters (substances or substance groups) that are regulated within this framework. All the substances are associated with various health outcomes, and many of them are classified as carcinogenic or probably/possibly carcinogenic with causal links. To quantify the health burden of the chemical substances included in the AAQD and DWD, we need information regarding population exposure, current baseline mortality/morbidity rates in the populations, and exposure-response functions (ERFs) or unit risks (URs) from previous epidemiological studies. During this study, we analyzed the availability of ERFs or URs and discussed their applicability in health impact assessments (HIAs). From the HIA perspective, ERFs─in terms of relative risk (RR), standardized mortality ratio (SMR), odds ratio (OR), or UR data─were available for many of the analyzed substances. However, for some substances such as acrylamide, antimony, boron, chlorate and chlorite, copper, microcystin-LR, and selenium, no risk measures could be identified. The aim of this study is to derive ERFs, which will allow HIAs for a larger number of chemicals when exposure data and baseline mortality/morbidity data are available. Currently, HIAs have largely focused only on main ambient pollutants such as particulate matter (PM10), fine particulate matter (PM2.5), nitrogen oxides (NOX), and ozone (O3). In contrast, health risks related to exposure to chemicals are much more diverse, and the health burdens should be quantified to a much greater extent.

Background: Air pollution has been linked to respiratory diseases, while the effects of greenness remain inconclusive. Objective: We investigated the associations between exposure to particulate matter (PM_2.5 and PM₁₀), black carbon (BC), nitrogen dioxide (NO₂), ozone (O₃), and greenness (normalized difference vegetation index, NDVI) with respiratory emergency room visits and hospitalizations across seven Northern European centers in the European Community Respiratory Health Survey (ECRHS) study.

Methods: We used modified mixed-effects Poisson regression to analyze associations of exposure in 1990, 2000 and mean exposure 1990–2000 with respiratory outcomes recorded duing ECRHS phases II and III. We assessed interactions of air pollution and greenness, and of atopic status (defined by nasal allergies and hay fever status) and greenness, on these outcomes.

Results: The analysis included 1675 participants, resulting in 119 emergency visits and 48 hospitalizations. Increased PM_2.5 by 5 μg/m³ was associated with higher relative risk (RR) of emergency visits (1990: RR 1.16, 95% CI: 1.00–1.35; 2000: RR 1.24, 95% CI: 0.98–1.57; 1990–2000: RR 1.17, 95% CI: 0.97–1.41) and hospitalizations (1990: RR 1.42, 95% CI: 1.00–2.01; 2000: RR 2.20, 95% CI: 1.43–3.38; 1990–2000: RR 1.44, 95% CI: 1.04–2.00). Similar trends were observed for PM₁₀, BC, and NO2, with only PM10 showing significant associations with hospitalizations across all periods. No associations were found for O₃. Greenness exposure was linked to more emergency visits in 2000 but to fewer hospitalizations in 1990. Significant interactions were observed between greenness and atopic status for emergency visits, and between NDVI with O₃ and BC for some time windows.

Conclusion: Long-term exposure to particulate matter was associated with increased emergency room visits and hospitalizations. Significant associations were observed for BC and NO₂ with hospitalizations. No link was found with O₃. Greenness indicated a lower risk of hospitalizations, but increased risks for emergency visits for those with atopic status.

Background: Voice problems have been reported in individuals with chronic cough, but population-based prevalence data are not yet available. While both conditions independently affect health and sick leave, their combined effects have not been studied. This study investigated the prevalence of voice problems in individuals with chronic cough and whether a cough duration of over 10 years is associated with a higher prevalence. Additionally, the relationship between chronic cough, voice problems, general health, and sick leave was explored.

Method: Cross-sectional and longitudinal data from the Respiratory Health In Northern Europe, RHINE III (n = 7,372) and RHINE IV (n = 10,101) surveys were analyzed. Logistic regression was used to analyze associations between chronic cough, voice problems, general health, and sick leave.

Results: Voice problems were reported by 30% of individuals with dry cough and 51% with productive cough, compared to 17% without cough. Among those with dry cough, prevalence increased from 24% (< 10 years) to 37% (> 10 years), with no significant difference for productive cough. Poor health was reported by 7.5% with dry cough and voice problems, 10% with productive cough and voice problems, and 1.7% without either condition. Chronic cough and voice problems were independently associated with poorer health, with an additive effect when co-occurring (adjusted Odds Ratio (95% CI): Dry cough 1.78 (1.34–2.37), Productive cough 2.03 (1.56–2.63), Voice problems 1.73 (1.54–1.94)). Chronic cough, but not voice problems, was linked to increased sick leave.

Conclusion: Voice problems are common among individuals with chronic cough, especially in productive cough. Both chronic cough and voice problems are independently associated with poorer general health, with additive effects when co-occurring. Chronic cough, but not voice problems, was associated with more sick leave. These findings highlight the need to address the combined burden of chronic cough and voice problems to improve patient outcomes and well-being.