Lancet Planetary Health最新文献

{"title":"Effects of city design on transport mode choice and exposure to health risks during and after a crisis: a retrospective observational analysis","authors":"Kerry A Nice PhD , Prof Jason Thompson PhD , Haifeng Zhao PhD , Sachith Seneviratne PhD , Belen Zapata-Diomedi PhD , Leandro Garcia PhD , Prof Ruth F Hunter PhD , Prof Rodrigo Siqueira Reis PhD , Prof Pedro C Hallal PhD , Prof Christopher Millett PhD , Ruoyu Wang PhD , Prof Mark Stevenson PhD","doi":"10.1016/S2542-5196(25)00088-9","DOIUrl":"10.1016/S2542-5196(25)00088-9","url":null,"abstract":"<div><h3>Background</h3><div>Rapid declines in city mobility during the early stages of the COVID-19 pandemic in 2020 resulted in reductions in citizens’ exposure to transport-related air pollution and associated health risks as many cities introduced non-pharmaceutical interventions designed to curb the spread of COVID-19. However, these benefits soon reversed during the pandemic's recovery phase (ie, from September, 2020, onwards), especially in cities with designs that afforded mode shifts away from public and active transport in favour of private motor vehicles. The aim of this study was to understand the association between global city designs, transport mode choices, and population-level risk exposure during 2020.</div></div><div><h3>Methods</h3><div>In this retrospective observational analysis, we assembled and analysed spatial datasets (including historical and predicted pollution levels, mobility indicators, and measures of individual disease transmission) and clustered 507 global cities using a graph neural network approach based on measures of the structural dimensions of each individual city's design and network structures of urban transportation systems. We compared city types on the basis of transportation mode shifts, air pollution levels, and associated health outcomes (ie, cardiovascular disease, ischaemic heart disease, respiratory disease, asthma, and reported COVID-19 cases) throughout 2020. We estimated risk reductions for these health outcomes across four phases of the pandemic, which we defined as the pre-pandemic, entry, mid-crisis, and recovery phases. We also identified city designs showing sustained reductions at the end of 2020 in transport-related air pollution (fine particulate matter [PM<sub>2·5</sub>] and nitrogen dioxide [NO<sub>2</sub>]) associated with reduced estimated risk of acute and chronic disease outcomes (ie, all-cause mortality, ischaemic heart disease mortality, cardiovascular disease, respiratory disease, and asthma).</div></div><div><h3>Findings</h3><div>The mean estimated reduction of global NO<sub>2</sub> concentrations across the observed cities from the beginning of the entry phase until the mid-crisis phase was 3·76 parts per billion (ppb), calculated as the difference between observed 2020 mean levels of 12·63 ppb and predicted mean levels (if the pandemic and mobility restrictions had not occurred) of 16·39 ppb. The mean estimated reduction of global PM<sub>2·5</sub> concentrations across the observed cities was 9·76 μg/m<sup>3</sup> (the difference between observed 2020 mean levels [29·03 μg/m<sup>3</sup>] and predicted mean levels [38·79 μg/m<sup>3</sup>]). If maintained over the long term, the estimated NO<sub>2</sub> reduction could have a substantial effect on reducing health risks for both acute and chronic disease, equating to an estimated overall reduction in all-cause mortality risk of 1·5% (95% CI 2·2–3·0), a reduction in cardiovascular mortality risk of 4·1% (2·6–6·0), and a reducti","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 6","pages":"Pages e467-e479"},"PeriodicalIF":24.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144261389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Desertification, Drought, and Planetary Health: UNCCD COP16 and the Future of Land","authors":"Liz Willetts","doi":"10.1016/S2542-5196(25)00119-6","DOIUrl":"10.1016/S2542-5196(25)00119-6","url":null,"abstract":"","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 6","pages":"Pages e452-e454"},"PeriodicalIF":24.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144095806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Putting food at the centre of learning: an evidence-based and practice-informed model of holistic food education in schools.","authors":"Melissa Vargas, Cristina Álvarez Sánchez, Vilma Tyler, Fatima Hachem","doi":"10.1016/S2542-5196(25)00033-6","DOIUrl":"https://doi.org/10.1016/S2542-5196(25)00033-6","url":null,"abstract":"<p><p>Food education in schools is increasingly being adopted as one of the key policy levers to support the shift towards healthier and more sustainable food practices worldwide. However, the way in which food education is designed and implemented is not often conducive to such goals. We propose a food learning model and process for designing holistic food education that fosters food competent children and adolescents as catalysts for change. The model applies evidence-based core principles required for effective food education, such as action-oriented goals that align with a student's contexts, co-ownership of the learning process, prioritising experiential learning, ensuring purposeful interactions, complementarity with the school food environment and beyond, and meaningful involvement of actors that influence children's food practices and perspectives. The process for designing food education programmes is anchored in the food learning model and highlights the importance of selecting the right entry points in the formal school system, assessment of learning needs, co-formulating competences, and the need for continuous and purposeful assessments of students' learning. We highlight the key challenges beyond programme design that must be addressed to enhance the success of food education, including the need to strengthen systemic capacity and improve the wider policy environment.</p>","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":" ","pages":""},"PeriodicalIF":24.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144144079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climate disaster effects on acute health care: a case study and model of the 2021 heatwave in British Columbia, Canada","authors":"Dylan G Clark MSc ,&nbsp;Kevin E Liang MD ,&nbsp;Ivy Cheng PhD ,&nbsp;Prof James D Ford PhD ,&nbsp;Kira Gossack-Keenan MD","doi":"10.1016/S2542-5196(25)00075-0","DOIUrl":"10.1016/S2542-5196(25)00075-0","url":null,"abstract":"<div><h3>Background</h3><div>Acute health-care systems are a final layer of protection against growing climate impacts on population health. Climate disasters over the past decade have resulted in surges of patients seeking emergency care when preventive measures fall short. We aimed to understand how acute health-care delivery and access is vulnerable to climate disasters.</div></div><div><h3>Methods</h3><div>We built a discrete event simulation model to replicate acute health-care system dynamics during Canada's deadliest climate disaster—the 2021 heatwave. We used public data and government reports to estimate resource capacity per capita and interconnected trajectories to define the movement of patients between resources. In an intervention scenario, we evaluated the efficacy of a package of three interventions in the emergency department and prehospital settings (upstaffing before the disaster, mass casualty procedures, and outpatient cooling beds). Across a 29-day period, we measured six key performance indicators (KPIs) to compare statistical changes in waiting times between baseline and intervention models (physician initial assessment waiting time; waiting time for emergency department bed among most acute patients; waiting time for emergency department bed among least acute patients; ambulance response time; boarding time; and total time in the emergency department). Using Monte Carlo methods, we ran both baseline and intervention models 100 times.</div></div><div><h3>Findings</h3><div>We validated baseline model outputs against real-world data, with no statistically significant differences in all KPI medians. The baseline model showed significant negative effects on five of the six KPIs during the heatwave compared with the preheatwave period. Under the intervention model, four KPIs had significant improvements during the heatwave compared with the preheatwave period while the other two KPIs did not significantly change. Notably, emergency department waiting times decreased by over 35% with the interventions.</div></div><div><h3>Interpretation</h3><div>The model replicated real-world patterns and was a valid representation of system dynamics. Our findings showed that even a small surge in patients can be detrimental to health-care access and delivery. The model also suggests that health-care delays during climate disasters can be avoidable with proactive planning.</div></div><div><h3>Funding</h3><div>The Government of British Columbia.</div></div>","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 5","pages":"Pages e356-e363"},"PeriodicalIF":24.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trends in population exposure to compound extreme-risk temperature and air pollution across 35 European countries: a modelling study","authors":"Zhao-Yue Chen MSc ,&nbsp;Hicham Achebak PhD ,&nbsp;Hervé Petetin PhD ,&nbsp;Raúl Fernando Méndez Turrubiates MSc ,&nbsp;Prof Yuming Guo PhD ,&nbsp;Prof Carlos Pérez García-Pando PhD ,&nbsp;Joan Ballester PhD","doi":"10.1016/S2542-5196(25)00048-8","DOIUrl":"10.1016/S2542-5196(25)00048-8","url":null,"abstract":"<div><h3>Background</h3><div>Despite ongoing efforts to reduce air pollution, the complex relationship between air pollution and climate change presents additional multifaceted challenges. The spatiotemporal co-occurrence of extreme temperatures and air pollution episodes remains understudied. Furthermore, current studies typically employ uniform temperature thresholds across broad areas, overlooking regional differences in health vulnerability. We aim to present a comprehensive assessment of extreme temperatures and air pollution, and to incorporate location-specific risk thresholds.</div></div><div><h3>Methods</h3><div>In this time series modelling study we analysed the changes in extreme-risk temperature (ERT) days for heat and cold in Europe from Jan 1, 2003 to Dec 31, 2020, considering time-varying temperature–mortality relationships based on regional mortality data (from Eurostat) from 35 European countries (543 million people). We used daily estimates of PM_2·5, PM₁₀, NO₂, and O₃ concentrations from quantile machine learning estimations at 0·1-degree to identify of heat-compound and cold-compound days co-occurring with air pollution levels exceeding WHO guidelines.</div></div><div><h3>Findings</h3><div>Cold-related mortality risk decreased over the study period across Europe, and adaptation to heat-related mortality was less pronounced. Between 2003 and 2020, annual cold-ERT days had decreased by 20·7 days per decade and annual heat-ERT days increased by 2·8 days per decade. Southeastern Europe had higher frequencies of both heat-ERT and cold-ERT days. Heat-O₃ events were the only increasing heat-compound episodes, with 2·6 more days per decade. Conversely, cold-compound episodes decreased by 15·2 days per decade with cold-PM_2·5 events remaining the predominant threat. Around 349 million Europeans were exposed to at least 1 cold-compound day annually, and around 295 million experienced at least one heat-compound day, including nearly 235 million affected by heat-O₃ compound episodes.</div></div><div><h3>Interpretation</h3><div>By identifying region-specific risk thresholds, our study reveals spatial disparities and changes in ERT events, particularly when coupled with air pollution. These findings are essential for developing targeted adaptation strategies, facilitating subsequent health assessments, and implementing effective measures to safeguard public health.</div></div><div><h3>Funding</h3><div>European Research Council and Ministerio de Ciencia e Innovación.</div></div>","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 5","pages":"Pages e384-e396"},"PeriodicalIF":24.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of climate and Aedes albopictus establishment on dengue and chikungunya outbreaks in Europe: a time-to-event analysis","authors":"Zia Farooq PhD ,&nbsp;Leo Segelmark MD ,&nbsp;Prof Joacim Rocklöv PhD ,&nbsp;Kate Lillepold MPH ,&nbsp;Maquines Odhiambo Sewe PhD ,&nbsp;Olivier J T Briet PhD ,&nbsp;Prof Jan C Semenza","doi":"10.1016/S2542-5196(25)00059-2","DOIUrl":"10.1016/S2542-5196(25)00059-2","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Background&lt;/h3&gt;&lt;div&gt;The rapid spread of the Asian tiger mosquito (&lt;em&gt;Aedes albopictus&lt;/em&gt;) poses a notable public health threat in Europe due to its ability to transmit tropical diseases such as dengue and chikungunya. We aimed to quantify the underlying drivers facilitating and accelerating Europe's transition from sporadic arbovirus outbreaks to &lt;em&gt;Aedes&lt;/em&gt;-borne disease endemicity, focusing on dengue and chikungunya outbreaks.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods&lt;/h3&gt;&lt;div&gt;We conducted a time-to-event analysis to investigate the period between establishment of &lt;em&gt;Ae albopictus&lt;/em&gt; and autochthonous dengue and chikungunya outbreaks across Nomenclature of Territorial Units for Statistics (NUTS) 3 regions in the EU. We incorporated data from the European Centre for Disease Prevention and Control, WHO, technical and surveillance reports, and other entomological data sources on regional &lt;em&gt;Ae albopictus&lt;/em&gt; establishment and subsequent dengue and chikungunya outbreaks from 1990 (when &lt;em&gt;Ae albopictus&lt;/em&gt; was first introduced to an EU country) to 2024. The main outcome was survival time (ie, the time from &lt;em&gt;Ae albopictus&lt;/em&gt; establishment to an outbreak of dengue or chikungunya), accounting for land-use types, demographic and socioeconomic factors, imported cases, and climatic variables via univariable and multivariable regression. To address recurrent outbreaks, we applied the Andersen–Gill extension of the Cox proportional hazards model to analyse all events. We further stratified regions into warm and cool groups on the basis of mean summer temperatures above or below 20°C and conducted a stratified analysis with Kaplan–Meier curves and the log-rank test to evaluate differences between these groups. We also estimated projected outbreak hazards from the 2030s to the 2060s at a decadal scale under three distinct shared socioeconomic pathways (SSPs; SSP1–2·6, SSP3–7·0, and SSP5–8·5) to assess the future impact of climate change on outbreak hazard estimates.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Findings&lt;/h3&gt;&lt;div&gt;Between 1990 and 2024, the interval from the first NUTS 3 regional establishment of &lt;em&gt;Ae albopictus&lt;/em&gt; to the first outbreak of dengue or chikungunya decreased from 25 years to less than 5 years. Similarly, the interval from the first outbreak to the second outbreak decreased from 12 years in 1990 to less than 1 year in 2024. Our regression analyses indicate that increasingly favourable climatic conditions play a significant role in this trend. A 1°C rise in mean summer temperature was associated with a hazard ratio of 1·55 (95% CI 1·30–1·85; p&lt;0·0001) after controlling for health-care expenditure and imported cases and land-use type. First outbreak events might have occurred more frequently and earlier in warmer regions than cooler ones (log-rank p=0·088), reflecting a lower probability of remaining outbreak-free over time. This trend is expected to intensify under extreme climate change scenarios, with projections under the SSP5–8·5 scen","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 5","pages":"Pages e374-e383"},"PeriodicalIF":24.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of climate change on arsenic concentrations in paddy rice and the associated dietary health risks in Asia: an experimental and modelling study","authors":"Dongming Wang MS ,&nbsp;Brent F Kim MHS ,&nbsp;Prof Keeve E Nachman PhD ,&nbsp;Andrea A Chiger PhD ,&nbsp;Prof Julie Herbstman PhD ,&nbsp;Irakli Loladze PhD ,&nbsp;Prof Fang-Jie Zhao PhD ,&nbsp;Chuan Chen PhD ,&nbsp;Axiang Gao PhD ,&nbsp;Prof Yongguan Zhu PhD ,&nbsp;Prof Fangbai Li PhD ,&nbsp;Prof Ren Fang Shen PhD ,&nbsp;Prof Xiaoyuan Yan PhD ,&nbsp;Jiabao Zhang PhD ,&nbsp;Chuang Cai PhD ,&nbsp;Lian Song PhD ,&nbsp;Min Shen PhD ,&nbsp;Chuanqi Ma MS ,&nbsp;Xiong Yang PhD ,&nbsp;Wei Zhou PhD ,&nbsp;Lewis H Ziska PhD","doi":"10.1016/S2542-5196(25)00055-5","DOIUrl":"10.1016/S2542-5196(25)00055-5","url":null,"abstract":"<div><h3>Background</h3><div>Rising global atmospheric carbon dioxide (CO₂) concentrations and surface temperatures could negatively affect rice yields and nutritional quality; however, their effects on arsenic accumulation in paddy rice have not been assessed concurrently. We aimed to assess the impact of increases in CO₂ and temperature (individually and in combination) on arsenic concentrations in rice, characterise soil properties that might influence arsenic uptake, and model the associated risks of cancer and other health outcomes due to increased arsenic exposure.</div></div><div><h3>Methods</h3><div>For this modelling study we performed in-situ multi-varietal trials using Free-Air CO₂ Enrichment platforms with and without supplemental temperature to examine the bioaccumulation of arsenic in paddy rice and the underlying biogeochemical mechanisms from 2014 to 2023. We modelled dietary inorganic arsenic exposure and the associated risks of cancer and non-cancer health outcomes via rice consumption for seven of the leading rice-consuming countries in east and southeast Asia.</div></div><div><h3>Findings</h3><div>Concomitant increases in CO₂ and temperature resulted in a synergistic increase of inorganic arsenic in rice grain. The observed increase is likely to be related to changes in soil biogeochemistry that favoured reduced arsenic species. Modelled consumption of rice under these conditions resulted in projected increases in inorganic arsenic exposure and lifetime cancer and health risks for multiple Asian countries by 2050.</div></div><div><h3>Interpretation</h3><div>Inorganic arsenic exposure and the associated health consequences might increase in rice grain grown in flooded systems with mid-century climate projections. The current assessment reinforces the urgent need for mitigation of arsenic exposure in rice relative to near-term climate change.</div></div><div><h3>Funding</h3><div>National Key Research and Development Program of China, National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, China, Carbon Peaking and Carbon Neutrality Special Fund for Science and Technology from Nanjing Science and Technology Bureau, Key Research and Development Program of Jiangsu Province, Erdos City Science and Technology Major Project, Science Foundation of the Chinese Academy of Sciences, Carbon Peaking and Carbon Neutrality Special Fund for Science and Technology from Jiangsu Science and Technology Department, and “0-1” Original Innovation Project of the Chinese Academy of Sciences.</div></div>","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 5","pages":"Pages e397-e409"},"PeriodicalIF":24.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climate change is redefining health-care delivery and preparedness","authors":"Renee N Salas","doi":"10.1016/S2542-5196(25)00111-1","DOIUrl":"10.1016/S2542-5196(25)00111-1","url":null,"abstract":"","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 5","pages":"Pages e350-e351"},"PeriodicalIF":24.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Planetary Health Research Digest","authors":"Cahal McQuillan","doi":"10.1016/S2542-5196(25)00117-2","DOIUrl":"10.1016/S2542-5196(25)00117-2","url":null,"abstract":"","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 5","pages":"Page e352"},"PeriodicalIF":24.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of air pollution exposure on menstrual cycle health using self-reported data from a mobile health app: a prospective, observational study","authors":"Priyanka N deSouza PhD ,&nbsp;Amanda A Shea PhD ,&nbsp;Virginia J Vitzthum PhD ,&nbsp;Fabio Duarte PhD ,&nbsp;Claire Gorman Hanly MS ,&nbsp;Meghan Timmons BA ,&nbsp;Patricia Huguelet MD ,&nbsp;Mary D Sammel ScD ,&nbsp;Carlo Ratti PhD ,&nbsp;Danielle Braun PhD ,&nbsp;Rachel C Nethery PhD","doi":"10.1016/S2542-5196(25)00080-4","DOIUrl":"10.1016/S2542-5196(25)00080-4","url":null,"abstract":"<div><h3>Background</h3><div>Toxicological evidence suggests that ambient air pollution has endocrine-disrupting properties that can affect menstrual cycle functioning, which represents an important marker of women's reproductive health. We aimed to estimate the effect of short-term and long-term PM_2·5 exposure on menstrual cycle outcomes across the USA, Brazil, and Mexico using self-reported data from a mobile health app.</div></div><div><h3>Methods</h3><div>For this prospective observational study, we collected de-identified self-reported data from the Clue mobile health app, in which users self-tracked menstruation cycles. For the current study, eligible participants were aged 18–44 years, were not using hormonal birth control, and lived in one of 230 cities in the USA, Mexico, or Brazil. The primary outcome of interest at the city level was the proportion of menstrual cycles with abnormally short length (&lt;24 days) and long length (&gt;38 days) of all cycles recorded. The primary outcome at the cycle level was a binary indicator: abnormal cycle length (&lt;24 days or &gt;38 days) or not (normal cycle length). We used regression analyses to evaluate associations between long-term PM_2·5 concentrations (mean concentration between 2016 and 2020) and the city-level outcomes after controlling for potential confounders. Conditional logistic regression models were used to evaluate associations between cycle-specific PM_2·5 and if a cycle was of abnormal length within an individual in the dataset, after controlling for time-varying factors.</div></div><div><h3>Findings</h3><div>Between Jan 1, 2016 and Dec 31, 2020, 92 550 app users residing in 230 cities across the USA, Brazil, and Mexico provided data corresponding to 2 220 281 menstrual cycles, and were included in our main cohort. A significant association was observed between long-term PM_2·5 exposure and the proportion of menstrual cycles of abnormally long or short duration (odds ratio [OR] 1·023 [95% CI 1·013–1·033]) and the proportion of cycles that were specifically abnormally long (OR 1·036 [1·023–1·049]) for every 10 μg/m³ increase in PM_2·5. No associations were identified between short-term PM_2·5 concentrations and abnormal cycle length.</div></div><div><h3>Interpretation</h3><div>These findings suggest that PM_2·5 exposure affects menstrual cycle outcomes. More research is needed to better elucidate the biological mechanisms through which PM_2·5 affects the menstrual cycle.</div></div><div><h3>Funding</h3><div>None.</div></div>","PeriodicalId":48548,"journal":{"name":"Lancet Planetary Health","volume":"9 5","pages":"Pages e364-e373"},"PeriodicalIF":24.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}