Projected local rain events due to climate change and the impacts on waterborne diseases in Vancouver, British Columbia, Canada.
Bimal K. Chhetri, Eleni Galanis, Stephen Sobie, Jordan Brubacher, Robert Balshaw, Michael Otterstatter, Sunny Mak, Marcus Lem, Mark Lysyshyn, Trevor Murdock, Manon Fleury, Kirsten Zickfeld, Mark Zubel, Len Clarkson, Tim K. Takaro
Environmental Health volume 18, Article number: 116 (2019) https://dx.doi.org/10.14288/1.0387512
Abstract
Background
Climate change is increasing the number and intensity of extreme weather events in many parts of the world. Precipitation extremes have been linked to both outbreaks and sporadic cases of waterborne illness. We have previously shown a link between heavy rain and turbidity to population-level risk of sporadic cryptosporidiosis and giardiasis in a major Canadian urban population. The risk increased with 30 or more dry days in the 60 days preceding the week of extreme rain. The goal of this study was to investigate the change in cryptosporidiosis and giardiasis risk due to climate change, primarily change in extreme precipitation.
Methods
Cases of cryptosporidiosis and giardiasis were extracted from a reportable disease system (1997–2009). We used distributed lag non-linear Poisson regression models and projections of the exposure-outcome relationship to estimate future illness (2020–2099). The climate projections are derived from twelve statistically downscaled regional climate models. Relative Concentration Pathway 8.5 was used to project precipitation derived from daily gridded weather observation data (~ 6 × 10 km resolution) covering the central of three adjacent watersheds serving metropolitan Vancouver for the 2020s, 2040s, 2060s and 2080s.
Results
Precipitation is predicted to steadily increase in these watersheds during the wet season (Oct. -Mar.) and decrease in other parts of the year up through the 2080s. More weeks with extreme rain (>90th percentile) are expected. These weeks are predicted to increase the annual rates of cryptosporidiosis and giardiasis by approximately 16% by the 2080s corresponding to an increase of 55–136 additional cases per year depending upon the climate model used. The predicted increase in the number of waterborne illness cases are during the wet months. The range in future projections compared to historical monthly case counts typically differed by 10–20% across climate models but the direction of change was consistent for all models.
Discussion
If new water filtration measures had not been implemented in our study area in 2010–2015, the risk of cryptosporidiosis and giardiasis would have been expected to increase with climate change, particularly precipitation changes. In addition to the predicted increase in the frequency and intensity of extreme precipitation events, the frequency and length of wet and dry spells could also affect the risk of waterborne diseases as we observed in the historical period. These findings add to the growing evidence regarding the need to prepare water systems to manage and become resilient to climate change-related health risks.
July 6 | 2020
/in Paper of the Week /by Kerolyn ShairsinghA scoping review on the relations between urban form and health: a focus on Canadian quantitative evidence.
McCormack GR, Cabaj J, Orpana H, Lukic R, Blackstaffe A, Goopy S, Hagel B, Keough N, Martinson R, Chapman J, Lee C, Tang J, Fabreau G.
Health Promot Chronic Dis Prev Can. 2019 May;39(5):187-200. doi: 10.24095/hpcdp.39.5.03.
Abstract
Plain Language Summary
The most frequently reported associations among Canadian studies on urban form and health outcomes were related to injury and weight status. Not all provinces and territories were represented in this review, with much of the evidence coming from studies in Ontario, Quebec, and Alberta. Objectively-measured aggregate built environment indicators, connectivity and route features, destinations, food environment, population density, and greenspace, parks and recreation features are associated with a range of modifiable health conditions and injury. This scoping review identifies that more Canadian research, with rigorous designs that allow for causal inference, is required to inform policy and practice.
June 23 | 2020
/in Paper of the Week /by Kerolyn ShairsinghLocal-Area Walkability and Socioeconomic Disparities of Cardiovascular Disease Mortality in Japan.
Koohsari MJ, Nakaya T, Hanibuchi T, Shibata A, Ishii K, Sugiyama T, Owen N, Oka K.
J Am Heart Assoc. 2020 Jun 9:e016152. doi: 10.1161/JAHA.119.016152
Abstract
Background: There are spatial disparities in cardiovascular disease (CVD) mortality related to area-level socioeconomic status (SES) disadvantage, but little is known about the spatial distribution of CVD mortality according to built environment factors. We examined joint associations of neighborhood walkability attributes and SES with CVD mortality rates through linkage of Japanese national data sets.
Methods and Results: National data were used from the 1824 municipalities (of the 1880 potentially eligible municipalities) across Japan. The outcome was mortality from CVD for a 5-year period (2008-2012) for each municipality. A national index of neighborhood deprivation was used as an indicator of municipality-level SES. A national walkability index (based on population density, road density, and access to commercial areas) was calculated. Compared with higher SES municipalities, relative rates for CVD mortality were significantly higher in medium SES municipalities (relative rate, 1.05; 95% CI, 1.02-1.07) and in lower SES municipalities (relative rate, 1.09; 95% CI, 1.07-1.12). There were walkability-related gradients in CVD mortality within the high and medium SES areas, in which lower walkability was associated with higher rates of mortality; however, walkability-related CVD mortality gradients were not apparent in lower SES municipalities.
Conclusions: CVD mortality rates varied not only by area-level SES but also by walkability. Those living in areas of lower walkability were at higher risk of CVD mortality, even if the areas have a higher SES. Our findings provide a novel element of the evidence base needed to inform better allocation of services and resources for CVD prevention.
June 9 | 2020
/in Paper of the Week /by Kerolyn ShairsinghBuilt Environment, Physical Activity, and Obesity: Findings from the International Physical Activity and Environment Network (IPEN) Adult Study.
Sallis JF, Cerin E, Kerr J, Adams MA, Sugiyama T, Christiansen LB, Schipperijn J, Davey R, Salvo D, Frank LD, De Bourdeaudhuij I, Owen N.
Annu Rev Public Health. 2020 Apr 2;41:119-139. doi: 10.1146/annurev-publhealth-040218-043657.
Abstract
Creating more physical activity-supportive built environments is recommended by the World Health Organization for controlling noncommunicable diseases. The IPEN (International Physical Activity and Environment Network) Adult Study was undertaken to provide international evidence on associations of built environments with physical activity and weight status in 12 countries on 5 continents (n > 14,000). This article presents reanalyzed data from eight primary papers to identify patterns of findings across studies. Neighborhood environment attributes, whether measured objectively or by self-report, were strongly related to all physical activity outcomes (accelerometer-assessed total physical activity, reported walking for transport and leisure) and meaningfully related to overweight/obesity. Multivariable indexes of built environment variables were more strongly related to most outcomes than were single-environment variables. Designing activity-supportive built environments should be a higher international health priority. Results provide evidence in support of global initiatives to increase physical activity and control noncommunicable diseases while achieving sustainable development goals.
Clearing the Air: How electric vehicles and cleaner trucks can reduce pollution, improve health and save lives | July 8th | 2020
/in Events, News, Webinars /by Eleanor SettonJULY 8TH (10am pacific | 1pm eastern)
CANCELLED
A recording of a previous webinar featuring this report is available here.
Understanding the benefits of cleaner air and how we can achieve lower pollution levels is key to effective healthy policy. “Clearing the Air: How electric vehicles and cleaner trucks can reduce pollution, improve health and save lives in the Greater Toronto and Hamilton Area” is being released today to mark Clean Air Day in Canada. This report quantifies the benefits of electrifying cars and buses and shifting to new more efficient trucks, and recommends policy actions governments can take to work towards achieving cleaner air.
Hear about the study highlights and talk with the report authors:
Laura Minet- Transportation Engineering, PhD Candidate, University of Toronto
Sarah Buchanan – Clean Economy Program Manager, Environmental Defence
Helen Doyle – Ontario Public Health Association Environmental Health Working Group
Marianne Hatzopoulou – Transportation and Air Quality Research Group, Associate Professor, University of Toronto
David Stieb- Public Health Physician, Environmental Health Science and Research Bureau, Health Canada
May 28 | 2020
/in Paper of the Week /by Kerolyn ShairsinghGlobal Land Use Regression Model for Nitrogen Dioxide Air Pollution
Andrew Larkin, Jeffrey A. Geddes, Randall V. Martin, Qingyang Xiao, Yang Liu, Julian D. Marshall, Michael Brauer, and Perry Hystad
Environ. Sci. Technol. 2017, 51, 12. DOI: 10.1021/acs.est.7b01148
Abstract
Nitrogen dioxide is a common air pollutant with growing evidence of health impacts independent of other common pollutants such as ozone and particulate matter. However, the worldwide distribution of NO2 exposure and associated impacts on health is still largely uncertain. To advance global exposure estimates we created a global nitrogen dioxide (NO2) land use regression model for 2011 using annual measurements from 5,220 air monitors in 58 countries. The model captured 54% of global NO2 variation, with a mean absolute error of 3.7 ppb. Regional performance varied from R2 = 0.42 (Africa) to 0.67 (South America). Repeated 10% cross-validation using bootstrap sampling (n = 10,000) demonstrated a robust performance with respect to air monitor sampling in North America, Europe, and Asia (adjusted R2 within 2%) but not for Africa and Oceania (adjusted R2 within 11%) where NO2 monitoring data are sparse. The final model included 10 variables that captured both between and within-city spatial gradients in NO2 concentrations. Variable contributions differed between continental regions, but major roads within 100 m and satellite-derived NO2 were consistently the strongest predictors. The resulting model can be used for global risk assessments and health studies, particularly in countries without existing NO2 monitoring data or models.
May 4 | 2020
/in Paper of the Week /by Mary SpeckHealth impact assessment of Philadelphia’s 2025 tree canopy cover goals.
Kondo MC, Mueller N, Locke DH, Roman LA, Rojas-Rueda D, Schinasi LH, Gascon M, Nieuwenhuijsen MJ.
Lancet Planet Health. 2020 Apr;4(4):e149-e157. doi: 10.1016/S2542-5196(20)30058-9
Abstract
BACKGROUND:
Cities across the world are undertaking ambitious projects to expand tree canopy by increasing the number of trees planted throughout public and private spaces. In epidemiological studies, greenspaces in urban environments have been associated with physical and mental health benefits for city dwellers. Greenworks Philadelphia is a plan to increase tree cover across Philadelphia (PA, USA) by the year 2025. We aimed to assess whether an increase in tree canopy or greenspace in Philadelphia could decrease mortality.
METHODS:
We did a greenspace health impact assessment to estimate the annual premature mortality burden for adult residents associated with projected changes in tree canopy cover in Philadelphia between 2014 and 2025. Using up-to-date exposure-response functions, we calculated the number of preventable annual premature deaths city-wide, and for areas of lower versus higher socioeconomic status, for each of three tree canopy scenarios: low, moderate and ambitious. The ambitious scenario reflected the city’s goal of 30% tree canopy cover in each of the city’s neighbourhoods; and low and moderate scenarios were based on the varying levels of plantable space across neighbourhoods.
FINDINGS:
We estimated that 403 (95% interval 298-618) premature deaths overall, including 244 (180-373) premature deaths in areas of lower socioeconomic status, could be prevented annually in Philadelphia if the city were able to meet its goal of increasing tree canopy cover to 30%.
INTERPRETATION:
Bringing all of Philadelphia, and particularly its poorer neighbourhoods, up to the 30% goal of tree canopy cover is not without challenge. Nevertheless, policies are warranted that value urban greening efforts as health-promoting and cost-saving measures.
April 14 | 2020
/in Paper of the Week /by Mary SpeckQuiet, clean, green, and active: A Navigation Guide systematic review of the impacts of spatially correlated urban exposures on a range of physical health outcomes.
Rugel EJ, Brauer M.
Environ Res. 2020 Mar 19;185:109388. [Epub ahead of print]
DOI:10.1016/j.envres.2020.109388
Abstract
BACKGROUND:
Recent epidemiologic analyses have considered impacts of multiple spatially correlated urban exposures, but this literature has not been systematically evaluated.
OBJECTIVES:
To characterize the long-term impacts of four distinct spatially correlated urban environmental exposures – traffic-related air pollution (TRAP), noise, natural spaces, and neighborhood walkability – by evaluating studies including measures of at least two such exposures in relationship to mortality, cardiovascular disease, chronic respiratory disease, allergy, type 2 diabetes, or reproductive outcomes.
METHODS:
Following the Navigation Guide framework, the literature was searched for studies published since 2003 and meeting predefined inclusion criteria. Identified studies were scored individually for risk of bias and all studies related to an exposure-group set were appraised for overall quality and strength of evidence.
RESULTS:
A total of 51 individual studies (TRAP and noise: n = 29; TRAP and natural spaces: n = 10; noise and natural spaces: n = 2; TRAP, noise, and natural spaces: n = 7; TRAP, noise, natural spaces, and walkability: n = 3) were included. When TRAP and noise were considered jointly, evidence was sufficient for increased cardiovascular morbidity with higher noise exposures; sufficient for no effect of TRAP on CVD morbidity; sufficient for increased mortality with higher TRAP exposures, but limited for noise; and limited for increased adverse reproductive outcomes with higher TRAP exposures and no effect of noise. Looking at natural spaces and TRAP, there was limited evidence for lower risk of chronic respiratory disease and small increases in birthweight with greater natural space; this relationship with birthweight persisted after adjustment for noise as well. Evidence was inadequate for all other exposure groups and outcomes.
DISCUSSION:
Studies that properly account for the complexity of relationships between urban form and physical health are limited but suggest that even highly correlated exposures may have distinct effects.
April 6 | 2020
/in Paper of the Week /by Mary SpeckTraffic-Related Air Pollution and Carotid Plaque Burden in a Canadian City With Low-Level Ambient Pollution.
Johnson M, Brook JR, Brook RD, Oiamo TH, Luginaah I, Peters PA, Spence JD.
J Am Heart Assoc. 2020 Apr 7;9(7):e013400. Epub 2020 Apr 2. DOI 10.1161/JAHA.119.013400
Abstract
Background:
The association between fine particulate matter and cardiovascular disease has been convincingly demonstrated. The role of traffic-related air pollutants is less clear. To better understand the role of traffic-related air pollutants in cardiovascular disease development, we examined associations between NO2, carotid atherosclerotic plaque, and cardiometabolic disorders associated with cardiovascular disease.
Methods and Results:
Cross-sectional analyses were conducted among 2227 patients (62.9±13.8 years; 49.5% women) from the Stroke Prevention and Atherosclerosis Research Centre (SPARC) in London, Ontario, Canada. Total carotid plaque area measured by ultrasound, cardiometabolic disorders, and residential locations were provided by SPARC medical records. Long-term outdoor residential NO2 concentrations were generated by a land use regression model. Associations between NO2, total carotid plaque area, and cardiometabolic disorders were examined using multiple regression models adjusted for age, sex, smoking, and socioeconomic status. Mean NO2 was 5.4±1.6 ppb in London, Ontario. NO2 was associated with a significant increase in plaque (3.4 mm2 total carotid plaque area per 1 ppb NO2), exhibiting a linear dose-response. NO2 was also positively associated with triglycerides, total cholesterol, and the ratio of low- to high-density lipoprotein cholesterol (P<0.05). Diabetes mellitus mediated the relationship between NO2 and total carotid plaque area (P<0.05).
Conclusions:
Our results demonstrate that even low levels of traffic-related air pollutants are linked to atherosclerotic plaque burden, an association that may be partially attributable to pollution-induced diabetes mellitus. Our findings suggest that reducing ambient concentrations in cities with NO2 below current standards would result in additional health benefits. Given the billions of people exposed to traffic emissions, our study supports the global public health significance of reducing air pollution.
March 30 | 2020
/in Paper of the Week /by Mary SpeckAir pollution and stunting: a missing link?
Sheela S Sinharoy, Thomas Clasen, Reynaldo Martorell.
The Lancet Global Health Comment Volume 8, Issue 4, April 2020, Pages e472-e475
https://doi.org/10.1016/S2214-109X(20)30063-2
Child linear growth impairment, particularly stunting, remains a global health challenge. Stunting is defined as a height-for-age Z-score more than two SDs below the WHO child growth standards reference median for age and sex. The number of children younger than 5 years who are stunted was 59 million (34%) in south Asia and 58 million (33%) in sub-Saharan Africa in 2018.1 Stunting is associated with poor child development, lower productivity and earnings in adulthood, and increased risk of chronic diseases later in life.2, 3 In this Comment, we argue that air pollution has been largely ignored as a potentially important cause of stunting, we outline a conceptual framework for how air pollution might lead to impaired linear growth in children, and we call for additional research into these mechanisms.
March 23 | 2020
/in Paper of the Week /by Mary SpeckProjected local rain events due to climate change and the impacts on waterborne diseases in Vancouver, British Columbia, Canada.
Bimal K. Chhetri, Eleni Galanis, Stephen Sobie, Jordan Brubacher, Robert Balshaw, Michael Otterstatter, Sunny Mak, Marcus Lem, Mark Lysyshyn, Trevor Murdock, Manon Fleury, Kirsten Zickfeld, Mark Zubel, Len Clarkson, Tim K. Takaro
Environmental Health volume 18, Article number: 116 (2019) https://dx.doi.org/10.14288/1.0387512
Abstract
Background
Climate change is increasing the number and intensity of extreme weather events in many parts of the world. Precipitation extremes have been linked to both outbreaks and sporadic cases of waterborne illness. We have previously shown a link between heavy rain and turbidity to population-level risk of sporadic cryptosporidiosis and giardiasis in a major Canadian urban population. The risk increased with 30 or more dry days in the 60 days preceding the week of extreme rain. The goal of this study was to investigate the change in cryptosporidiosis and giardiasis risk due to climate change, primarily change in extreme precipitation.
Methods
Cases of cryptosporidiosis and giardiasis were extracted from a reportable disease system (1997–2009). We used distributed lag non-linear Poisson regression models and projections of the exposure-outcome relationship to estimate future illness (2020–2099). The climate projections are derived from twelve statistically downscaled regional climate models. Relative Concentration Pathway 8.5 was used to project precipitation derived from daily gridded weather observation data (~ 6 × 10 km resolution) covering the central of three adjacent watersheds serving metropolitan Vancouver for the 2020s, 2040s, 2060s and 2080s.
Results
Precipitation is predicted to steadily increase in these watersheds during the wet season (Oct. -Mar.) and decrease in other parts of the year up through the 2080s. More weeks with extreme rain (>90th percentile) are expected. These weeks are predicted to increase the annual rates of cryptosporidiosis and giardiasis by approximately 16% by the 2080s corresponding to an increase of 55–136 additional cases per year depending upon the climate model used. The predicted increase in the number of waterborne illness cases are during the wet months. The range in future projections compared to historical monthly case counts typically differed by 10–20% across climate models but the direction of change was consistent for all models.
Discussion
If new water filtration measures had not been implemented in our study area in 2010–2015, the risk of cryptosporidiosis and giardiasis would have been expected to increase with climate change, particularly precipitation changes. In addition to the predicted increase in the frequency and intensity of extreme precipitation events, the frequency and length of wet and dry spells could also affect the risk of waterborne diseases as we observed in the historical period. These findings add to the growing evidence regarding the need to prepare water systems to manage and become resilient to climate change-related health risks.