Abstract Background Exposure to particulate air pollution seem to be a contributing cause to lung cancer incidence; however, the role of the size and composition of the particles is still unclear. The objective was to assess the association between source-specific concentrations of ambient particulate air pollution and lung cancer incidence in a Swedish cohort in a low-level area. Methods Participants in the Västerbotten intervention programme cohort from Northern Sweden were recruited between January 1990 and December 2014 and followed until diagnosis for lung cancer, as defined by Swedish national hospital, cause of death and pharmaceutical registers. Exposure to total particulate matter with aerodynamic diameter ≤ 10 µm (PM10) and ≤ 2.5 µm (PM2.5) as well as source-specific PM concentrations from traffic (PM10-traffic), exhaust (PM2.5-exhaust) and wood burning (PM2.5-wood burning) was estimated at each individual’s home address using dispersion models with high spatial resolution (down to 35 x 35 m2). For the years of follow-up, the moving average of source-specific pollutants was calculated for the time windows 1–5 years (lag 1–5) and 6–10 years (lag 6–10) preceding the outcome. Cox regression models were used to assess Hazard Ratios (HRs) and 95% Confidence Intervals (CIs) for the association between air pollution exposure and lung cancer incidence, adjusted for relevant potential confounding factors. Results The median age of the 51,064 participants was 40 years at baseline. During 421,466 person-years of follow-up, 253 incident cases of lung cancer were observed. Non-statistically significant risk increases associated with PM10, PM2.5, PM10-traffic, PM2.5-exhaust and PM10-wood burning, respectively in single-pollutant unadjusted models. The risk estimates changed considerably by adjustment for individual-level baseline covariates as well as area-level socioeconomics. The HR for incident lung cancer associated with a 1 µg/m3 increase in PM2.5-exhaust was 1.20 (95% Confidence Interval, CI: 0.65–2.23), whereas the corresponding HR associated with PM2.5-wood burning was 1.05 (95% CI: 0.70–1.57), in single-pollutant models. Conclusions There was some evidence for an association between exposure to particles from traffic, but not wood burning, and incidence of lung-cancer in this register-based study, but not for with particles from wood burning.

Air pollution is increasingly discussed as a risk factor for dementia, but the biological mechanisms are not yet fully understood. Biological markers like telomere length are relevant to study with air pollution, as they are associated with aging and dementia. The study aimed to investigate the relationship between source-specific air pollution exposure and telomere length in a low-level air pollution area, and whether this potential relationship depended on future dementia status. The data originated from the Betula study in Northern Sweden, where 509 participants recruited between 1988 and 1995 were included to investigate the association between annual mean air pollution concentrations at the participants’ residences and relative leukocyte telomere length using a linear regression model. No association was observed between air pollution and telomere length, with regression slope estimates close to zero and p-values > 0.10 (e.g. PM2.5_total: β = 0.01 (-0.011, 0.025) and BC_total: β = 0.03 (95% CI: -0.046, 0.114). There were indications of a positive association between longer telomere length and higher exposure to air pollution among individuals later diagnosed with dementia (N = 74), but these findings were not conclusive (p-values > 0.10) (PM2.5_total: β = 0.03, p-value = 0.12; BC_total: β = 0.11, p-value = 0.17). Although not statistically significant, our findings contribute to the evidence from low-exposure settings, and it is important to report these types of findings for a balanced understanding of potential health effects.

Background: A large part of the Swedish population is exposed to higher levels of air pollution than the health-centered air quality guidelines recommended by the World Health Organization (WHO). Aim: The aim of the study was to illustrate the potential health benefits of cleaner air in Sweden by conducting a comprehensive health impact assessment, using a population sample of 100,000 individuals representing the country’s demographics. Methods: Exposure-response functions for various health outcomes were derived from epidemiological literature, mainly from systematic reviews and low-exposure settings. Two hypothetical scenarios were studied: a 1 µg/m3 decrease in particulate matter with an aerodynamic diameter <2.5µm (PM2.5) and nitrogen dioxide (NO2), and a reduction in PM2.5 or NO2 from average exposure corresponding to Sweden’s Clean Air objectives to WHO’s air quality guidelines. Results: The findings demonstrated that even a modest decrease in air pollution concentrations can yield significant health benefits. For example, reducing PM2.5 by 1 µg/m3 was projected to correspond to a 1% to 2% decrease in mortality, a 2% reduction in myocardial infarction cases, a 4% decrease in stroke incidence, a 2% decline in chronic obstructive pulmonary disease, and a 1% decreases in lung cancer and type 2 diabetes annually. Moreover, this reduction is estimated to lower childhood asthma cases, incidences of hypertension during pregnancy, and premature births by 3%, 3% and 2%, respectively, each year. Conclusions: The results highlighted that even minor enhancements in air quality would lead to substantial improvements in public health.

BACKGROUND:During the initial phase of the COVID-19 pandemic, reductions in air pollution were globally observed owing to decreased human activities, underscoring the potential for cleaner air through shifts in human behaviour. OBJECTIVES:The objective of the present study was to hypothetically estimate the resulting population health impacts in Malmö, Sweden, if these improvements in air quality were to become permanent. METHODS:We utilized air pollution data from two measurement campaigns conducted in the spring of 2019 and the spring of 2020 for our Health Impact Assessment, applying standard methods. This assessment involved making assumptions about baseline population risk and using established concentration-response functions. RESULTS:In the spring of 2020, the NO2 concentrations exhibited an average decrease of 6.6 μg/m3 (42%) decrease and PM2.5 concentrations a 1.9 μg/m3 (22%) decrease, compared to the spring of 2019. If sustained, such improvements could lead to an estimated 1-3% decrease in premature deaths, a 2% decrease in preeclampsia cases, a 6% decrease in low birthweight children, a 4% decrease in bronchitis cases among children, a 2% decrease in asthma cases, a 0.2% decrease in hospital admissions for respiratory diagnoses, and an estimated 11% decrease in dementia cases annually. CONCLUSION:The findings illustrate the potential for enhanced health in Malmö due to improved air quality. Efforts to combat air pollution and implement long-term strategies, such as those targeting urban mobility and commuting patterns, are essential for the health and well-being of both local and global populations.

The aim of this study was to investigate the relationship between source-specific ambient particulate air pollution concentrations and the incidence of dementia. The study encompassed 70,057 participants from the Västerbotten intervention program cohort in Northern Sweden with a median age of 40 years at baseline. High-resolution dispersion models were employed to estimate source-specific particulate matter (PM) concentrations, such as PM10 and PM2.5 from traffic, exhaust, and biomass (mainly wood) burning, at the residential addresses of each participant. Cox regression models, adjusted for potential confounding factors, were used for the assessment. Over 884,847 person-years of follow-up, 409 incident dementia cases, identified through national registers, were observed. The study population’s average exposure to annual mean total PM10 and PM2.5 lag 1–5 years was 9.50 µg/m3 and 5.61 µg/m3, respectively. Increased risks were identified for PM10-Traffic (35% [95% CI 0–82%]) and PM2.5-Exhaust (33% [95% CI − 2 to 79%]) in the second exposure tertile for lag 1–5 years, although no such risks were observed in the third tertile. Interestingly, a negative association was observed between PM2.5-Wood burning and the risk of dementia. In summary, this register-based study did not conclusively establish a strong association between air pollution exposure and the incidence of dementia. While some evidence indicated elevated risks for PM10-Traffic and PM2.5-Exhaust, and conversely, a negative association for PM2.5-Wood burning, no clear exposure–response relationships were evident.

A prevalent solution to accommodate population growth due to urbanization is densification. However, this often pushes new residential housing closer to roads, increasing exposure to both noise and air pollution. The present study's aim was to estimate the health impacts of road traffic-related noise and air pollution for a low-income area (Drottninghog) in Helsingborg, Sweden, according to pre-densification (2012) and post-densification (2030) scenarios. Road traffic noise was simulated at the fa & ccedil;ade of residential buildings using the Nordic prediction method, and exposure was assessed using SoundPLAN. Exposure-response functions (ERF) from the WHO were utilized for the following health outcomes associated with noise: annoyance, adverse sleep disturbance, ischemic heart disease (IHD) incidence and IHD mortality. Air pollution (nitrogen dioxide, NO2) was assessed using a Gaussian dispersion model (AERMODE). Health outcomes associated with NO2 included natural cause mortality, pediatric asthma, respiratory hospitalizations and low birth weight (LBW). ERFs were derived from meta-analyses. Health impact assessments were then performed for both scenarios. Densifying Drottninghog according to the municipality's planned strategy would lead to a 15 % unit increase in the proportion of residents exposed to road traffic noise above the WHO's health-based guideline value (53 dB (A) Lden). This was estimated to markedly increase the proportion of residents highly annoyed by traffic noise (7.4-13.9 %) as well as those highly sleep disturbed (3.0-4.9 %). IHD incidence and IHD mortality attributed to noise would increase by an estimated 49 % and 44 %, respectively, post-densification. NO2 exposure was estimated to increase slightly (0.7 mu g/m 3 ) post-densification, which would contribute to an estimated 4-6 % increase in natural cause mortality, pediatric asthma, respiratory hospitalization and LBW. Urban planning initiatives need to consider these prevalent urban environmental exposures and integrate a public health perspective into densification strategies. Doing so can create synergies in the built environment that promote healthy, sustainable cities.

In this study, the long-term mortality effects associated with exposure to PM10 (particles with an aerodynamic diameter smaller than or equal to 10 µm), PM2.5 (particles with an aerodynamic diameter smaller than or equal to 2.5 µm), BC (black carbon), and NOx (nitrogen oxides) were analyzed in a cohort in southern Sweden during the period from 1991 to 2016. Participants (those residing in Malmö, Sweden, born between 1923 and 1950) were randomly recruited from 1991 to 1996. At enrollment, 30,438 participants underwent a health screening, which consisted of questionnaires about lifestyle and diet, a clinical examination, and blood sampling. Mortality data were retrieved from the Swedish National Cause of Death Register. The modeled concentrations of PM10, PM2.5, BC, and NOx at the cohort participants’ home addresses were used to assess air pollution exposure. Cox proportional hazard models were used to estimate the associations between long-term exposure to PM10, PM2.5, BC, and NOx and the time until death among the participants during the period from 1991 to 2016. The hazard ratios (HRs) associated with an interquartile range (IQR) increase in each air pollutant were calculated based on the exposure lag windows of the same year (lag0), 1–5 years (lag1–5), and 6–10 years (lag6–10). Three models were used with varying adjustments for possible confounders including both single-pollutant estimates and two-pollutant estimates. With adjustments for all covariates, the HRs for PM10, PM2.5, BC, and NOx in the single-pollutant models at lag1–5 were 1.06 (95% CI: 1.02–1.11), 1.01 (95% CI: 0.95–1.08), 1.07 (95% CI: 1.04–1.11), and 1.11 (95% CI: 1.07–1.16) per IQR increase, respectively. The HRs, in most cases, decreased with the inclusion of a larger number of covariates in the models. The most robust associations were shown for NOx, with statistically significant positive HRs in all the models. An overall conclusion is that road traffic-related pollutants had a significant association with mortality in the cohort.

BACKGROUND AND AIM: In many places worldwide there is an ongoing urbanization, often achieved through densification. An increased number of inhabitants in an area often leads to both increased traffic and placement of new buildings closer to roads, and thus increased population exposure to road traffic noise. The aim of the study was to estimate and compare the health impacts of road traffic noise exposure for an urban area pre- and post-densification. METHOD: Noise at the façade of residential buildings within the area of Drottninghög located in the city of Helsingborg, Southern Sweden, was simulated using the Nordic prediction method for road traffic and exposure assessed for all people living in the area Geographical Information Systems software SoundPLAN. Health impact assessments based on exposure-response functions from The Worlds Health Organisation was calculated including road traffic noise annoyance and adverse sleep disturbance. RESULTS: A large proportion (70%) of the population was found to be exposed above the health-based guideline value of Lden 53 dB(A) in pre-densification scenario. In the post-densification scenario this proportion increased even further to 85% of the population. The proportion of annoyed in the pre-densification scenario were 5.8% compared to 11.2% in the post-densification and the proportion adversely sleep disturbed 2.8% respectively 4.3%. CONCLUSIONS: Densifying the area in accordance with the municipal planned strategy will considerably increase the proportion of annoyed and sleep disturbed part of the population living in the area. Health is an important aspect in creating a sustainable city and urban planning initiatives needs to be more ambitious.

In this study, long-term mortality effects associated with exposure to PM10, PM2.5, BC (black carbon), and NOx were analyzed in a cohort in southern Sweden during the period from 1991‒2016. Participants (those residing in Malmö, Sweden, born between 1923‒1950) were randomly recruited from 1991‒1996. At enrollment, 30,438 participants underwent a health screening, which consisted of questionnaires about lifestyle and diet, a clinical examination, and blood sampling. Mortality data were retrieved from the Swedish national cause of death register. The modeled concentrations of PM10 (particles with an aerodynamic diameter smaller than or equal to 10 µm), PM2.5 (particles with an aerodynamic diameter smaller than or equal to 2.5 µm), BC (black carbon), and NOx (nitrogen oxides) at the cohort participants' home addresses were used to assess air pollution exposure. Cox proportional hazard models were used to estimate the associations between long-term exposure to PM10, PM2.5, BC, and NOx and the time until death among the participants during the period from 1991‒2016. The hazard ratios (HRs) associated with an interquartile range (IQR) increase in each air pollutant were calculated based on the exposure lag windows of the same year (lag0), 1‒5 years (lag1‒5), and 6‒10 years (lag6‒10). Three models were used with varying adjustments for possible confounders including both single-pollutant estimates and two-pollutant estimates. With adjustments for all covariates, the HRs for PM10, PM2.5, BC, and NOx in the single-pollutant models at lag1‒5 were 1.06 (95% CI: 1.02‒1.11), 1.01 (95% CI: 0.95‒1.08), 1.07 (95% CI: 1.04‒1.11), and 1.11 (95% CI: 1.07‒1.16) per IQR increase, respectively. The HRs were in most cases decreased by the inclusion of a larger number of covariates in the models. The most robust associations were shown for NOx, with statistically significant positive HRs in all models. An overall conclusion is that road traffic-related pollutants had a significant association with mortality in the cohort.

AIMS:The aim of the study was to describe child health in relation to housing renovations in more than 800 rental units, consisting of repairs of dilapidated kitchens and bathrooms, in the disadvantaged neighbourhood of Herrgården in Rosengård, Malmö, Sweden.METHODS:Data on housing conditions and self-reported health were collected during home visits to families living in Herrgården (building renovations area) and a comparison area (neighbouring Törnrosen, with generally better housing conditions). At baseline, 130 families with 359 children participated, while 51 families with 127 children participated at follow-up. All data were collected between 2010 and 2012. Additionally, regional register data on health-care usage/in- and outpatient contacts within the public health-care system between 2008 and 2013 were also collected for all 8715 children registered as living in the two areas.RESULTS:Self-reported health seemed to somewhat improve in both areas, with 74% versus 86% and 78% versus 88% reporting good or very good health in Herrgården and in the comparison area at baseline and follow-up, respectively. In Herrgården, crowdedness increased, while it decreased in the comparison area. The number of health-care contacts remained stable over time in Herrgården, while it decreased in the comparison area.CONCLUSIONS:Partial housing renovations did not seem to result in clear health improvements as measured with the indicators used in the present study. This could possibly be due to persisting health effects due to increased crowdedness or persisting poor housing conditions, as only kitchens and bathrooms were renovated.

BACKGROUND:Environmental noise is an important environmental exposure that can affect health. An association between transportation noise and breast cancer incidence has been suggested, although current evidence is limited. We investigated the pooled association between long-term exposure to transportation noise and breast cancer incidence. METHODS:Pooled data from eight Nordic cohorts provided a study population of 111,492 women. Road, railway, and aircraft noise were modelled at residential addresses. Breast cancer incidence (all, estrogen receptor (ER) positive, and ER negative) was derived from cancer registries. Hazard ratios (HR) were estimated using Cox Proportional Hazards Models, adjusting main models for sociodemographic and lifestyle variables together with long-term exposure to air pollution. RESULTS:A total of 93,859 women were included in the analyses, of whom 5,875 developed breast cancer. The median (5th-95th percentile) 5-year residential road traffic noise was 54.8 (40.0-67.8) dB Lden, and among those exposed, the median railway noise was 51.0 (41.2-65.8) dB Lden. We observed a pooled HR for breast cancer (95 % confidence interval (CI)) of 1.03 (0.99-1.06) per 10 dB increase in 5-year mean exposure to road traffic noise, and 1.03 (95 % CI: 0.96-1.11) for railway noise, after adjustment for lifestyle and sociodemographic covariates. HRs remained unchanged in analyses with further adjustment for PM2.5 and attenuated when adjusted for NO2 (HRs from 1.02 to 1.01), in analyses using the same sample. For aircraft noise, no association was observed. The associations did not vary by ER status for any noise source. In analyses using <60 dB as a cutoff, we found HRs of 1.08 (0.99-1.18) for road traffic and 1.19 (0.95-1.49) for railway noise. CONCLUSIONS:We found weak associations between road and railway noise and breast cancer risk. More high-quality prospective studies are needed, particularly among those exposed to railway and aircraft noise before conclusions regarding noise as a risk factor for breast cancer can be made.

Evidence of air pollution exposure, namely, ambient particulate matter (PM), during pregnancy and an increased risk of autism in children is growing; however, the unique PM sources that contribute to this association are currently unknown. The aim of the present study was to investigate local, source-specific ambient PM exposure during pregnancy and its associations with childhood autism, specifically, and autism spectrum disorders (ASD) as a group. A cohort of 40,245 singleton births from 2000 to 2009 in Scania, Sweden, was combined with data on locally emitted PM with an aerodynamic diameter < 2.5 µm (PM2.5). A flat, two-dimensional dispersion model was used to assess local PM2.5 concentrations (all-source PM2.5, small-scale residential heating- mainly wood burning, tailpipe exhaust, and vehicle wear-and-tear) at the mother's residential address during pregnancy. Associations were analyzed using binary logistic regression. Exposure to local PM2.5 during pregnancy from each of the investigated sources was associated with childhood autism in the fully adjusted models. For ASD, similar, but less pronounced, associations were found. The results add to existing evidence that exposure to air pollution during pregnancy may be associated with an increased risk of childhood autism. Further, these findings suggest that locally produced emissions from both residential wood burning and road traffic-related sources (tailpipe exhaust and vehicle wear-and-tear) contribute to this association.

Diabetes mellitus (DM) incidence have been assessed in connection with air pollution exposure in several studies; however, few have investigated associations with source-specific local emissions. This study aims to estimate the risk of DM incidence associated with source-specific air pollution in a Swedish cohort with relatively low exposure. Individuals in the Va center dot sterbotten intervention programme cohort were followed until either a DM diagnosis or initiation of treatment with glucose-lowering medication occurred. Dispersion models with high spatial resolution were used to estimate annual mean concentrations of particulate matter (PM) with aerodynamic diameter <= 10 mu m (PM10) and <= 2.5 mu m (PM2.5) at individual addresses. Hazard ratios were estimated using Cox regression models in relation to moving averages 1-5 years preceding the outcome. During the study period, 1479 incident cases of DM were observed during 261,703 person-years of follow-up. Increased incidence of DM was observed in association with PM10 (4% [95% CI: -54-137%] per 10 mu g/m3), PM10-traffic (2% [95% CI: -6-11%] per 1 mu g/m3) and PM2.5-exhaust (11% [95% CI: -39-103%] per 1 mu g/m3). A negative association was found for both PM2.5 (-18% [95% CI: -99-66%] per 5 mu g/m3), but only in the 2nd exposure tertile (-10% [95% CI: -25-9%] compared to the first tertile), and PM2.5-woodburning (-30% [95% CI: -49-4%] per 1 mu g/m3). In twopollutant models including PM2.5-woodburning, there was an 11% [95% CI: -11-38%], 6% [95% CI: -16-34%], 13% [95% CI: -7-36%] and 17% [95% CI: 4-41%] higher risk in the 3rd tertile of PM10, PM2.5, PM10-traffic and PM2.5-exhaust, respectively, compared to the 1st. Although the results lacked in precision they are generally in line with the current evidence detailing particulate matter air pollution from traffic as an environmental risk factor for DM.

While urbanization provides many opportunities to those arriving in thriving urban areas, a greater number of residents necessitates the expansion of housing and infrastructure. This is often achieved through densification, which can lead to increased noise, particularly through increased road traffic. A key challenge of promoting healthy urban planning is to understand potential health effects, especially on the local level. The aim of the present study is, therefore, to estimate and compare the health impacts of road traffic noise exposure for various urban densification scenarios within a neighborhood (Lorensborg) in Malmö, Sweden. The three scenarios include 1) Present-day, representing the study area as it is presently organized; 2) Planned municipal strategy (the city of Malmö's own densification plans) and 3) Health-centred, which involves major structural alterations and reflects an effort prioritize a health-centred approach. Noise was modelled using the Nordic prediction method for road traffic. Health outcomes included noise annoyance, adverse sleep disturbance, ischemic heart disease (IHD) incidence and mortality. Within all scenarios, a large proportion of the study population was exposed above the WHO's health-based guideline value (Lden 53 dB): >80% for Present-day and Planned municipal strategy scenarios, and almost 50% in the Health-centred scenario. Still, densifying Lorensborg (population ≈9,600) according to the Health-centred scenario could prevent 549 cases of highly annoyed, 193 cases of adverse sleep disturbance, 4.7 new cases of IHD (8.9% of total cases), and 1.5 deaths due to IHD (17.8% of IHD mortality) annually. The results demonstrated that it is possible to considerably lower the health impact with a more health-centred densification strategy. Important co-benefits for public and environmental health include air pollution reduction and green space creation, although their health effects were not quantified in the present study. Urban planning initiatives must be more ambitious in order to create healthy, sustainable cities.

Air pollution is one of the leading causes of morbidity and mortality worldwide. Low-emission zones (LEZ) have been increasingly implemented in cities throughout Europe as a measure to reduce the adverse health effects and premature deaths associated with traffic-related air pollution. In the present study, a health impact analysis was conducted to estimate the effect of a hypothetical LEZ on mortality and morbidity in Malmö, Sweden. Baseline health statistics were gathered from health registers and applied to each resident according to individual-level data on age and/or sex. Concentration-response parameters were derived from current epidemiological literature, specifically meta-analyses. A Gaussian dispersion model (AERMOD) combined with a detailed emission database was used to calculate NO2 emissions from traffic, which could be applied on an individual-level using data on each person's residential coordinates. The adjusted exposure scenario replaced all vehicles on municipal roads having Euro 5 or lower emission standards with Euro 6 equivalents. This LEZ would, on average, decrease NO2 concentrations by 13.4%, preventing an estimated 9-26 deaths in Malmö each year. Additionally, 12 respiratory disease hospitalizations, 8 childhood asthma cases, and 9 cases of hypertensive disorders of pregnancy were estimated to be avoided annually. These results suggest that LEZs can effectively improve air quality, reduce greenhouse gas emissions, and safeguard public health.

While prenatal exposure to ambient air pollution has been shown to be associated with reduced birth weight, there is substantial heterogeneity across studies, and few epidemiological studies have utilized source-specific exposure data. The aim of the present study was, therefore, to investigate the associations between local, source-specific exposure to fine particulate matter (PM2.5) during pregnancy and birth weight. An administrative cohort comprising 40,245 singleton births from 2000 to 2009 in Scania, Sweden, was combined with data on relevant covariates. Investigated sources of PM2.5 included all local sources together as well as tailpipe exhaust, vehicle wear-and-tear, and small-scale residential heating separately. The relationships between these exposures, represented as interquartile range (IQR) increases, and birth weight (continuous) and low birth weight (LBW; <2500 g) were analyzed in crude and adjusted models. Each local PM2.5 source investigated was associated with reduced birth weight; average decreases varied by source (12–34 g). Only small-scale residential heating was clearly associated with LBW (adjusted odds ratio: 1.14 (95% confidence interval: 1.04–1.26) per IQR increase). These results add to existing evidence that prenatal exposure to ambient air pollution disrupts fetal growth and suggest that PM2.5 from both vehicles and small-scale residential heating may reduce birth weight.

Air pollution poses a threat to human health, with pregnant women and their developing fetuses being particularly vulnerable. A high dual burden of ambient and indoor air pollution exposure has been identified in Ethiopia, but studies investigating their effects on adverse birth outcomes are currently lacking. This study explores the association between ambient air pollution (NOX and NO2) and indoor air pollution (cooking fuel type) and fetal and neonatal death in Adama, Ethiopia. A prospective cohort of mothers and their babies was used, into which pregnant women were recruited at their first antenatal visit (n = 2085) from November 2015 to February 2018. Previously developed land-use regression models were utilized to assess ambient concentrations of NOX and NO2 at the residential address, whereas data on cooking fuel type was derived from questionnaires. Birth outcome data was obtained from self-reported questionnaire responses during the participant's postnatal visit or by phone if an in-person meeting was not possible. Binary logistic regression was employed to assess associations within the final study population (n = 1616) using both univariate and multivariate models; the latter of which adjusted for age, education, parity, and HIV status. Odds ratios (OR) and their corresponding 95% confidence intervals (CI) were reported. Within the cohort, 69 instances of fetal death (n = 16 miscarriages; n = 53 stillbirths) and 16 cases of neonatal death were identified. The findings suggest a tendency towards an association between ambient NOX and NO2 exposure during pregnancy and an increased risk of fetal death overall as well as stillbirth, specifically. However, statistical significance was not observed. Results for indoor air pollution and neonatal death were inconclusive. As limited evidence on the effects of exposure to ambient air pollution on adverse birth outcomes exists in Sub-Saharan Africa and Ethiopia, additional studies with larger study populations should be conducted.

Air pollution causes premature mortality and morbidity globally, but these adverse health effects occur over proportionately in low- and middle-income countries. Lack of both air pollution data and knowledge of its spatial distribution in African countries have been suggested to lead to an underestimation of health effects from air pollution. This study aims to measure nitrogen oxides (NOx), as well as nitrogen dioxide (NO2), to develop Land Use Regression (LUR) models in the city of Adama, Ethiopia. NOx and NO2 was measured at over 40 sites during six days in both the wet and dry seasons. Throughout the city, measured mean levels of NOx and NO2 were 29.0 µg/m3 and 13.1 µg/m3, respectively. The developed LUR models explained 68% of the NOx variances and 75% of the NO2. Both models included similar geographical predictor variables (related to roads, industries, and transportation administration areas) as those included in prior LUR models. The models were validated by using leave-one-out cross-validation and tested for spatial autocorrelation and multicollinearity. The performance of the models was good, and they are feasible to use to predict variance in annual average NOx and NO2 concentrations. The models developed will be used in future epidemiological and health impact assessment studies. Such studies may potentially support mitigation action and improve public health.