Environmental Epidemiology最新文献

{"title":"Evaluating the association between longitudinal exposure to a PFAS mixture and adolescent cardiometabolic risk in the HOME Study","authors":"Elvira S. Fleury, J. Kuiper, J. Buckley, G. Papandonatos, K. Cecil, Aimin Chen, Charles B. Eaton, Heidi J Kalkwarf, B. Lanphear, K. Yolton, Joseph M. Braun","doi":"10.1097/EE9.0000000000000289","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000289","url":null,"abstract":"Background: Exposure to per- and polyfluoroalkyl substances (PFAS) throughout gestation and childhood may impact cardiometabolic risk. Methods: In 179 HOME Study participants (Cincinnati, OH; recruited 2003–2006), we used latent profile analysis to identify two distinct patterns of PFAS exposure from serum concentrations of four PFAS measured at birth and ages 3, 8, and 12 years. We assessed the homeostatic model of insulin resistance, triglycerides-to-high-density lipoprotein cholesterol ratio, leptin-to-adiponectin ratio, systolic blood pressure, visceral fat, and hemoglobin A1c levels at age 12 years. We used multivariable linear regression to assess the association of membership in the longitudinal PFAS mixture exposure group with a summary measure of overall cardiometabolic risk and individual components. Results: One PFAS exposure profile (n = 66, 39%) had higher geometric means of all PFAS across all visits than the other. Although adjusted associations were null in the full sample, child sex modified the association of longitudinal PFAS mixture exposure group with overall cardiometabolic risk, leptin-to-adiponectin ratio, systolic blood pressure, and visceral fat (interaction term P values: 0.02–0.08). Females in the higher exposure group had higher cardiometabolic risk scores (ß = 0.43; 95% CI = −0.08, 0.94), systolic blood pressures (ß = 0.6; 95% CI = 0.1, 1.1), and visceral fat (ß = 0.44; 95% CI = −0.13, 1.01); males had lower cardiometabolic risk scores (ß = −0.52; 95% CI = −1.06, −0.06), leptin-to-adiponectin ratios (ß = −0.7; 95% CI = −1.29, −0.1), systolic blood pressures (ß = −0.14; 95% CI = −0.7, 0.41), and visceral fat (ß = −0.52; 95% CI = −0.84, −0.19). Conclusions: Exposure to this PFAS mixture throughout childhood may have sex-specific effects on adolescent cardiometabolic risk.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139438031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Associations of per- and polyfluoroalkyl substances and nonalcoholic fatty liver disease in the United States adult population, 2003–2018","authors":"Harry D. Momo, Christian S. Alvarez, M. Purdue, Barry I. Graubard, K. McGlynn","doi":"10.1097/EE9.0000000000000284","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000284","url":null,"abstract":"Background: Nonalcoholic fatty liver disease (NAFLD) is the most common liver disorder worldwide and a leading cause of liver-related mortality. Prior studies have linked per- and polyfluoroalkyl substances (PFAS) exposure to liver dysfunction and alterations in metabolic pathways, but the extent of a PFAS-NAFLD relationship is unclear. Thus, the aim of the current study was to examine whether there were associations between PFAS exposures and NAFLD in the US adult population over a 16-year period. Methods: Data from 10,234 persons who participated in the National Health and Nutrition Examination Survey between 2003 and 2018 were analyzed. Odds ratios and 95% confidence intervals were calculated using multivariable logistic regression for the associations between PFAS and NAFLD, defined by the Hepatic Steatosis Index (NAFLD-HSI), the Fatty Liver Index (NAFLD-FLI), and by Transient Elastography with Controlled Attenuation Parameter (NAFLD-TE-CAP). Results: Overall, there was a significant inverse association between total PFAS and NAFLD-HSI (P-trend = 0.04). Significant inverse associations were also found between perfluorohexane sulfonic acid (PFHxS) and NAFLD-HSI (P-trend = 0.04), and NAFLD-FLI (P-trend = 0.03). Analysis by time period, 2003–2010 versus 2011–2018, found that while inverse associations were more apparent during the latter period when total PFAS (P-trend = 0.02), PFHxS (P-trend = 0.04), and perfluorooctanoic acid (PFOA) (P-trend = 0.03) were inversely associated with NAFLD-HSI and PFOA was inversely associated with NAFLD-FLI (P-trend = 0.05), there were no significant interaction effects. No significant associations between the PFAS and NAFLD-TE-CAP were found. Conclusions: The current study found no evidence of a positive association between the most common PFAS and NAFLD in the US population.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Urinary biomarkers of exposure to toxic and essential elements: A comparison of infants fed with human milk or formula","authors":"Talia D. Pikounis, Kassaundra L. Amann, B. P. Jackson, T. Punshon, D. Gilbert-Diamond, S. Korrick, M. R. Karagas, K. L. Cottingham","doi":"10.1097/EE9.0000000000000286","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000286","url":null,"abstract":"Background: Early-life exposure to nonessential (toxic) and essential trace elements can influence child development. Although infant formula powders and the water used to reconstitute them can contain higher concentrations of many elements compared with human milk, the influence of feeding mode on reliable biomarkers of infant exposure has rarely been demonstrated. Methods: We evaluated associations between urinary biomarkers and feeding mode (exclusively human milk, exclusively formula, or combination-fed) for four toxic (arsenic, cadmium, nickel, and uranium) and three essential elements (cobalt, molybdenum, and selenium) using general linear models. Results: A total of 462 participants from the rural New Hampshire Birth Cohort Study were on average 6 weeks old between July 2012 and March 2019 and had urine samples, 3-day food diaries, and relevant covariate data available. In adjusted models, urinary arsenic was 5.15 (95% confidence interval = 4.04, 6.58), molybdenum was 19.02 (14.13–25.59), and selenium was 1.51 (1.35–1.68) times higher in infants fed exclusively with formula compared with infants fed exclusively with human milk. By contrast, urinary uranium was 0.59 (0.46–0.75) and cobalt was 0.78 (0.65–0.95) times lower with formula feeding than human milk feeding. Conclusion: Our findings suggest that infant exposure to several potentially toxic elements varies by feeding mode, as concentrations of reliable urinary biomarkers were higher with formula or human milk, depending on the element. Importantly, exposure to arsenic increased with household tap water arsenic regardless of feeding mode, suggesting that all infants could be at risk in populations with high concentrations of arsenic in drinking water.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139441964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensitive development windows of prenatal air pollution and cognitive functioning in preschool age Mexican children","authors":"H. Hsu, Jamil M. Lane, L. Schnaas, Brent A. Coull, Erika Osorio-Valencia, Y. Chiu, Ander Wilson, Allan C. Just, I. Kloog, David Bellinger, M. Téllez-Rojo, Robert O. Wright","doi":"10.1097/EE9.0000000000000291","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000291","url":null,"abstract":"Introduction: Neurotoxicity resulting from air pollution is of increasing concern. Considering exposure timing effects on neurodevelopmental impairments may be as important as the exposure dose. We used distributed lag regression to determine the sensitive windows of prenatal exposure to fine particulate matter (PM2.5) on children’s cognition in a birth cohort in Mexico. Methods: Analysis included 553 full-term (≥37 weeks gestation) children. Prenatal daily PM2.5 exposure was estimated using a validated satellite-based spatiotemporal model. McCarthy Scales of Children’s Abilities (MSCA) were used to assess children’s cognitive function at 4–5 years old (lower scores indicate poorer performance). To identify susceptibility windows, we used Bayesian distributed lag interaction models to examine associations between prenatal PM2.5 levels and MSCA. This allowed us to estimate vulnerable windows while testing for effect modification. Results: After adjusting for maternal age, socioeconomic status, child age, and sex, Bayesian distributed lag interaction models showed significant associations between increased PM2.5 levels and decreased general cognitive index scores at 31–35 gestation weeks, decreased quantitative scale scores at 30–36 weeks, decreased motor scale scores at 30–36 weeks, and decreased verbal scale scores at 37–38 weeks. Estimated cumulative effects (CE) of PM2.5 across pregnancy showed significant associations with general cognitive index (CE^ = −0.35, 95% confidence interval [CI] = −0.68, −0.01), quantitative scale (CE^ = −0.27, 95% CI = −0.74, −0.02), motor scale (CE^ = −0.25, 95% CI = −0.44, −0.05), and verbal scale (CE^ = −0.2, 95% CI = −0.43, −0.02). No significant sex interactions were observed. Conclusions: Prenatal exposure to PM2.5, particularly late pregnancy, was inversely associated with subscales of MSCA. Using data-driven methods to identify sensitive window may provide insight into the mechanisms of neurodevelopmental impairment due to pollution.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139444376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Child exposure to organophosphate and pyrethroid insecticides measured in urine, wristbands, and household dust and its implications for child health in South Africa: A panel study","authors":"A. Veludo, M. Röösli, M. A. Dalvie, Petra Stuchlík Fišerová, R. Prokes, P. Příbylová, P. Šenk, Jiří Kohoutek, Mufaro Mugari, Jana Klánová, Anke Huss, D. Figueiredo, H. Mol, Jonatan Dias, C. Degrendele, S. Fuhrimann","doi":"10.1097/EE9.0000000000000282","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000282","url":null,"abstract":"Background: Children in agricultural areas are exposed to organophosphate (OP) and pyrethroid (PYR) insecticides. This explorative study investigated child exposure to OPs and PYRs, comparing temporal and spatial exposure variability within and among urine, wristbands, and dust samples. Methods: During spraying season 2018, 38 South African children in two agricultural areas (Grabouw/Hex River Valley) and settings (farm/village) participated in a seven-day study. Child urine and household dust samples were collected on days 1 and 7. Children and their guardians were wearing silicone wristbands for seven days. Intraclass correlation coefficients (ICCs) evaluated temporal agreements between repeated urine and dust samples, Spearman rank correlations (Rs) evaluated the correlations among matrices, and linear mixed-effect models investigated spatial exposure predictors. A risk assessment was performed using reverse dosimetry. Results: Eighteen OPs/PYRs were targeted in urine, wristbands, and dust. Levels of chlorpyrifos in dust (ICC = 0.92) and diethylphosphate biomarker in urine (ICC = 0.42) showed strong and moderate temporal agreement between day 1 and day 7, respectively. Weak agreements were observed for all others. There was mostly a weak correlation among the three matrices (Rs = −0.12 to 0.35), except for chlorpyrifos in dust and its biomarker 3,5,6-trichloro-2-pyridinol in urine (Rs = 0.44). No differences in exposure levels between living locations were observed. However, 21% of the urine biomarker levels exceeded the health-risk threshold for OP exposure. Conclusions: Observed high short-term variability in exposure levels during spraying season highlights the need for repeated sampling. The weak correlation between the exposure matrices points to different environmental and behavioral exposure pathways. Exceeding risk thresholds for OP should be further investigated.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139148131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association between prenatal and childhood PM2.5 exposure and preadolescent anxiety and depressive symptoms","authors":"L. Mcguinn, Iván Gutiérrez-Avila, M. Rosa, Allan C. Just, Brent Coull, I. Kloog, Marcela Tamayo Ortiz, H. Harari, Sandra Martinez, Erika Osorio-Valencia, M. Téllez-Rojo, Daniel N. Klein, Rosalind J. Wright, Robert O. Wright","doi":"10.1097/EE9.0000000000000283","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000283","url":null,"abstract":"Background: Fine particulate matter (PM2.5) exposure has been linked to anxiety and depression in adults; however, there is limited research in the younger populations, in which symptoms often first arise. Methods: We examined the association between early-life PM2.5 exposure and symptoms of anxiety and depression in a cohort of 8–11-year-olds in Mexico City. Anxiety and depressive symptoms were assessed using the Spanish versions of the Revised Children’s Manifest Anxiety Scale and Children’s Depression Inventory. Daily PM2.5 was estimated using a satellite-based exposure model and averaged over several early and recent exposure windows. Linear and logistic regression models were used to estimate the change in symptoms with each 5-µg/m3 increase in PM2.5. Models were adjusted for child’s age, child’s sex, maternal age, maternal socioeconomic status, season of conception, and temperature. Results: Average anxiety and depressive symptom T-scores were 51.0 (range 33–73) and 53.4 (range 44–90), respectively. We observed consistent findings for exposures around the fourth year of life, as this was present for both continuous and dichotomized anxiety symptoms, in both independent exposure models and distributed lag modeling approaches. This window was also observed for elevated depressive symptoms. An additional consistent finding was for PM2.5 exposure during early pregnancy in relation to both clinically elevated anxiety and depressive symptoms, this was seen in both traditional and distributed lag modeling approaches. Conclusion: Both early life and recent PM2.5 exposure were associated with higher mental health symptoms in the child highlighting the role of PM2.5 in the etiology of these conditions.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139000665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Power outages and pediatric unintentional injury hospitalizations in New York State","authors":"Alexander J Northrop, Nina M. Flores, V. Do, Perry E. Sheffield, Joan A. Casey","doi":"10.1097/EE9.0000000000000287","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000287","url":null,"abstract":"Background: In the past decade, electrical power disruptions (outages) have increased in the United States, especially those attributable to weather events. These outages have a range of health impacts but are largely unstudied in children. Here, we investigated the association between outages and unintentional injury hospitalizations, a leading cause of childhood morbidity. Methods: The study setting was New York State (NYS) from 2017 to 2020. Outage exposure was defined as ≥10%, ≥20%, and ≥50% of customers from a power operating locality without power, ascertained from NYS Department of Public Service records and stratified by rural, urban non-New York City (NYC), and NYC regions. Outcome daily block group-level pediatric injury hospitalization data was from the Statewide Planning and Research Cooperative System (SPARCS). We leveraged a case-crossover study design with logistic conditional regression. Results: We identified 23,093 unintentional injury hospitalizations in children <18 years with complete block group and exposure data. Most hospitalizations occurred in urban regions (90%), whereas outages were more likely in rural than urban areas. In urban non-NYC regions, outages ≥4 hours were associated with 30% increased odds of all-cause unintentional injury hospitalizations when ≥50% of customers were without power. Analyses by injury subtype revealed increasing point estimates as the proportion of customers exposed increased. These results, however, had wide confidence intervals. Conclusions: Outage exposure differed significantly across rural, urban non-NYC, and NYC regions across New York. Especially at the highest outage threshold, we observed an increased risk of pediatric unintentional injury hospitalizations.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138974134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association between outdoor temperature and fatal police shootings in the United States, 2015–2021","authors":"Ellen Martinson, Howard Chang, R. D’Souza, S. Ebelt, N. Scovronick","doi":"10.1097/EE9.0000000000000267","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000267","url":null,"abstract":"Background: Here, we investigate the association between outdoor temperature and fatal police shootings in the United States between 2015 and 2021. Methods: We conducted a time-stratified case-crossover study. Data on fatal police shootings were from the Washington Post’s Fatal Force database and temperature data were from Daymet. Results: A 5°C increase in maximum same-day temperature was associated with a 1.033 (95% CI = 1.002, 1.065) increased odds of a fatal police shooting. In stratified analyses, the strongest associations were observed in victims who were armed (OR, 1.052 [95% CI = 1.017, 1.088), White (OR, 1.052 [95% CI = 1.006, 1.100), or aged 45+ (OR, 1.110 [95% CI = 1.044, 1.181]). In additional subgroup analyses, relative risks were also generally higher among those who were armed. Conclusions: There is evidence of an association between outdoor temperature and fatal police shootings in the United States, particularly when the victims were reported as armed. This study cannot determine if the associations are a result of any specific causes (e.g., increased police aggression or other factors).","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138627698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sociodemographic inequalities in long-term exposure to air pollution, road traffic noise, and greenness: A population-based cohort study of women","authors":"Lara Stucki, Staffan Betnér, Jenny Selander, M. Lõhmus, A. Åkesson, C. Eriksson","doi":"10.1097/EE9.0000000000000279","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000279","url":null,"abstract":"Background: Recent evidence suggests environmental health inequalities both within and between European countries and socially deprived groups may be more susceptible to pollution. However, evidence is still inconclusive and additional studies are warranted. This study aims to investigate sociodemographic inequalities in long-term residential exposure to air pollution, road traffic noise, and greenness, taking lifestyle and degree of urbanization into account. Methods: In total 20,407 women, born 1914–48 residing in Uppsala County, Sweden, were followed between 1997 and 2017. Time-varying sociodemographic variables were obtained from registers, and questionnaires provided lifestyle information. Generalized estimating equations were used to compute beta-coefficients (β) and 95% confidence intervals (95% CI) for associations between sociodemographic and lifestyle variables and spatial-temporal modeled particulate matter (PM2.5, PM10), nitrogen dioxide (NO2), road traffic noise and greenness. All models were additionally stratified by urbanization type. Results: Urban area residency was the most important predictor of high exposure to air pollution and noise, and to low greenness. For instance, β for NO2 was −2.92 (95% CI = −3.00, −2.83) and −3.10 (95% CI = −3.18, −3.01) µg/m3 in suburban and rural areas, respectively, compared with urban areas. For greenness, the opposite held true with corresponding β of 0.059 (95% CI = 0.056, 0.062) and 0.095 (95% CI = 0.092, 0.098). Within urban areas, elderly, unmarried and well-educated women had the highest environmental burden. However, less pronounced, and even reversed associations were found in suburban and rural areas. Conclusion: This study provides evidence of a mixed pattern of environmental health inequalities across sociodemographic groups in urban areas.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138626049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of urban trees and total vegetation on asthma development in children","authors":"Louise Duquesne, Elhadji Anassour Laouan Sidi, C. Plante, Ying Liu, Naizhuo Zhao, Éric Lavigne, Kate Zinszer, Rita Sousa-Silva, Michel Fournier, Paul J. Villeneuve, David J. Kaiser, A. Smargiassi","doi":"10.1097/EE9.0000000000000280","DOIUrl":"https://doi.org/10.1097/EE9.0000000000000280","url":null,"abstract":"Objective: We aimed to assess whether the influence of urban vegetation on asthma development in children (<13 years) varies by type (e.g., total vegetation, tree type, and grass) and season. Methods: We used a cohort of all children born in Montreal, Canada, between 2000 and 2015. Children and cases were identified from linked medico-administrative databases. Exposure to residential vegetation was estimated using the Normalized Difference Vegetation Index (NDVI) for total vegetation and using the total area covered by deciduous and evergreen crowns for trees in 250 m buffers centered on residential postal codes. Seasonal variations in vegetation were modeled by setting values to zero on days outside of pollen and leaf-on seasons. Cox models with vegetation exposures, age as a time axis, and adjusted for sex, material deprivation, and health region were used to estimate hazard ratios (HR) for asthma development. Results: We followed 352,946 children for a total of 1,732,064 person-years and identified 30,816 incident cases of asthma. While annual vegetation (total and trees) measures did not appear to be associated with asthma development, models for pollen and leaf-on seasons yielded significant nonlinear associations. The risk of developing asthma was lower in children exposed to high levels (>33,300 m2) of deciduous crown area for the leaf-on season (HR = 0.69; 95% confidence interval [CI] = 0.67, 0.72) and increased for the pollen season (HR = 1.07; 95% CI =1.02, 1.12), compared with unexposed children. Similar results were found with the Normalized Difference Vegetation Index. Conclusion: The relationship between urban vegetation and childhood asthma development is nonlinear and influenced by vegetation characteristics, from protective during the leaf-on season to harmful during the pollen season.","PeriodicalId":11713,"journal":{"name":"Environmental Epidemiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139270152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}