Sarah B Henderson

BC Centre for Disease Control · Environmental Health Services

Western North America experienced an unprecedented extreme heat event (EHE) in 2021, characterized by high temperatures and reduced air quality. There were approximately 740 excess deaths during the EHE in the province of British Columbia, making it one of the deadliest weather events in Canadian history. It is important to understand who is at ris...

The likelihood of exposure to overheated indoor environments is increasing as climate change is exacerbating the frequency and severity of hot weather and extreme heat events (EHE). Consequently, vulnerable populations will face serious health risks from indoor overheating. While the relationship between EHE and human health has been assessed in re...

Western North America experienced an unprecedented extreme heat event (EHE) in early summer 2021. In the province of British Columbia (BC), this event was associated with an estimated 740 excess deaths, making it one of the deadliest weather events in Canadian history. This study uses a population-based case-control design to compare 1597 adults (c...

In late June 2021 a heatwave of unprecedented magnitude impacted the Pacific Northwest region of Canada and the United States. Many locations broke alltime maximum temperature records by more than 5 °C, and the Canadian national temperature record was broken by 4.6 °C, with a new record temperature of 49.6 °C. Here, we provide a comprehensive summa...

The 2017 and 2018 wildfire seasons in British Columbia (BC), Canada were unprecedented. Among all the pollutants in wildfire smoke, fine particulate matter (PM2.5) poses the most significant risk to human health. There is limited research on prenatal wildfire smoke exposure and its impacts on infant health. We used a population-based nested case-co...

The unprecedented 2021 Heat Dome caused wide-ranging and long-lasting impacts in western Canada, including 619 confirmed heat-related deaths in British Columbia, a doubling of emergency medical calls, increased hospitalisations, infrastructure failures and stress on plants and animals. However, such varied socio-economic consequences of extreme hea...

Increased frequency, intensity, and duration of wildfires are intensifying exposure to direct and smoke-related hazards in many areas, leading to evacuation and smoke-related effects on health and health systems that can affect regions extending over thousands of kilometres. Effective preparation and response are currently hampered by inadequate tr...

Odors are a topic of emerging environmental health interest given their potential links to air quality, health, well-being, and quality of life. However, odors have traditionally been challenging to study given variability in individual sensitivity and perception, atmospheric physico-chemical processes, and emissions of mixtures of odorous contamin...

Setting The potential for exposure to indoor radon varies dramatically across British Columbia (BC) due to varied geology. Individuals may struggle to understand their exposure risk and agencies may struggle to understand the value of population-level programs and policies to mitigate risk. Intervention The BC Centre for Disease Control (BCCDC) es...

With the growing climate change crisis, public health agencies and practitioners must increasingly develop guidance documents addressing the public health risks and protective measures associated with multi-hazard events. Our Policy and Practice Review aims to assess current public health guidance and related messaging about co-exposure to wildfire...

People who consume high quantities of seafood are at a heightened risk for marine biotoxin exposure. Coastal Indigenous peoples may experience higher levels of risk than the general population due to their reliance on traditional marine foods. Most evidence on the health risks associated with biotoxins focus on a single exposure at one point in tim...

The health risks associated with wildfires are expected to increase due to climate change. Children are susceptible to wildfire smoke, but little is known about indoor smoke exposure at childcare facilities. The objective of this analysis was to estimate the effects of outdoor PM2.5 and wildfire smoke episodes on indoor PM2.5 at childcare facilitie...

Landscape fires are an integral component of the Earth system and a feature of prehistoric, subsistence, and industrial economies. Specific spatiotemporal patterns of landscape fire occur in different locations around the world, shaped by the interactions between environmental and human drivers of fire activity. Seven distinct types of landscape fi...

Climate change is causing more frequent extreme heat events (EHEs). Healthcare facilities serve individuals susceptible to adverse health outcomes from heat exposure. This study describes temperature variability inside and outside of an older inpatient healthcare facility in Vancouver, British Columbia (BC), Canada during an unprecedented EHE in 20...

Background: The 2017 and 2018 wildfire seasons in British Columbia (BC), Canada were unprecedented. Among all the pollutants in wildfire smoke, fine particulate matter (PM2.5) poses the most significant risk to human health. There is limited research on prenatal wildfire-related PM2.5 exposure and its impacts on infant health. Objectives: We assess...

Human populations and ecosystems are extensively exposed to pesticides. Most nations lack the capacity to control pesticide contamination and have limited availability of pesticide use information. Ecuador is a country with intense pesticide use with high exposure risks to humans and the environment, although relative or combined risks are not well...

Background: Previous research has shown that cocaine-associated deaths occur more frequently in hot weather, which has not been described for other illicit drugs or combinations of drugs. The study objective was to evaluate the relation between temperature and risk of death related to cocaine, opioids and amphetamines in British Columbia, Canada....

Non-tailpipe emissions driven by springtime road dust in norther latitude communities is increasing in importance for air pollution control and improving our understanding of the health effects of chemical mixtures from particulate matter exposure. High-volume samples from a near-road site indicated that days affected by springtime road dust are su...

A growing body of evidence indicates that exposure to air pollution affects cognitive performance; however, few studies have assessed this in the context of repeated measures within a large group of individuals or in a population with a large age range. In this study, we evaluate the associations between long-term exposure to fine particulate matte...

Wildfire smoke is a rapidly growing threat to global cardiovascular health. We review the literature linking wildfire smoke exposures to cardiovascular effects. We find substantial evidence that short-term exposures are associated with key cardiovascular outcomes, including mortality, hospitalization, and acute coronary syndrome. Wildfire smoke exp...

Purpose of Review Increasing wildfire size and severity across the western United States has created an environmental and social crisis that must be approached from a transdisciplinary perspective. Climate change and more than a century of fire exclusion and wildfire suppression have led to contemporary wildfires with more severe environmental impa...

Attributing individual deaths to extreme heat events (EHE) in Canada and elsewhere is important for understanding the risk factors, protective interventions, and burden of mortality associated with climate change. However, there is currently no single mechanism for identifying individual deaths due to EHE and different agencies have taken different...

Exposure to biomass smoke has been associated with a wide range of acute and chronic health outcomes. Over the past decades, the frequency and intensity of wildfires has increased in many areas, resulting in longer smoke episodes with higher concentrations of fine particulate matter (PM2.5). There are also many communities where seasonal open burni...

Background Residential wood burning is a major source of fine particulate matter (PM2.5) during winter and a leading contributor to air pollution. Exposure to woodsmoke PM2.5 is associated with many health effects, so it is important to characterize the magnitude and spatial variability in exposures. However, high infrastructure and maintenance cos...

Background: There is increasing evidence that long-term exposure to fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)] may adversely impact cognitive performance. Wildfire smoke is one of the biggest sources of PM2.5 and concentrations are likely to increase under climate change. However, little is known about how short-term expos...

Wildfire smoke events are increasing in British Columbia (BC), Canada and environmental and public health agencies are responsible for communicating the health-related risks and mitigation strategies. To evaluate and identify opportunities for improving public communications about wildfire smoke and associated health risks we collaborated with end-...

In late June to early July 2021 a heatwave of unprecedented magnitude impacted the Pacific Northwest region, lands colonially named British Columbia (BC) and Alberta (AB) in Canada, and Washington (WA) and Oregon (OR) in the United States. Many locations broke all-time maximum daily temperature records by more than 5°C. The standing Canadian nation...

This review addresses knowledge gaps in cannabis cultivation facility (CCF) air emissions by synthesizing the peer-reviewed and gray literature. Focus areas include compounds emitted, air quality indoors and outdoors, odor assessment, and the potential health effects of emitted compounds. Studies suggest that β-myrcene is a tracer candidate for CCF...

Background: British Columbia, Canada, was impacted by a record-setting heat dome in early summer 2021. Most households in greater Vancouver do not have air conditioning, and there was a 440% increase in community deaths during the event. Readily available data were analyzed to inform modifications to the public health response during subsequent eve...

Wildfire smoke exposure is associated with a range of acute health outcomes, which can be more severe in individuals with underlying health conditions. Currently, there is limited information on the susceptibility of healthcare facilities to smoke infiltration. As part of a larger study to address this gap, a rehabilitation facility in Vancouver, C...

Odours from a wide range of sources can affect local air quality at different times and with different intensities. Unlike air pollutants such as fine particulate matter (PM2.5) and ground-level ozone (O3), there is no strong scientific evidence directly linking exposure to odours with specific health effects. Although odours are often characterize...

Wildland fires are diminishing air quality on a seasonal and regional basis, raising concerns about respiratory health risks to the public and occupational groups. This American Thoracic Society (ATS) workshop was convened in 2019 to meet the growing health threat of wildland fire smoke. The workshop brought together a multi-disciplinary group of 1...

Background: The modular British Columbia Asthma Prediction System (BCAPS) is designed to reduce information burden during wildfire smoke events by automatically gathering, integrating, generating, and visualizing data for public health users. The BCAPS framework comprises five flexible and geographically scalable modules: (1) historic data on fine...

Objective: Smoke from burning biomass is an important source of fine particulate matter (PM2.5), but the health risks may not be fully captured by the Canadian Air Quality Health Index (AQHI). In May 2018, the province of British Columbia launched an evidence-based amendment (AQHI-Plus) to improve AQHI performance for wildfire smoke, but the AQHI-P...

As we enter the wildfire season in the northern hemisphere, the potential for a dangerous interaction between SARS-CoV-2 and smoke pollution should be recognized and acknowledged. This is challenging because the public health threat of COVID-19 is immediate and clear, whereas the public health threat of wildfire smoke seems distant and uncertain in...

Background Extreme heat events have been associated with excess morbidity and mortality worldwide. Previous research mainly evaluated extreme heat exposures at the municipal and local scales, but individuals are exposed in much smaller areas. The goal of this study was to assess whether land use regression (LUR) models could be developed for air te...

BACKGROUND: Exposure to fine particulate matter (PM 2:5) during wildfire seasons has been associated with adverse health outcomes. Previous studies have focused on daily exposure, but PM 2:5 levels in smoke events can vary considerably within 1 d. OBJECTIVES: We aimed to assess the immediate and lagged relationship between sub-daily exposure to P...

Smoke from wildfires contains many air pollutants of concern and epidemiological studies have identified associations between exposure to wildfire smoke PM2.5 and mortality and respiratory morbidity, and a possible association with cardiovascular morbidity. For this study, a retrospective analysis of air quality modelling was performed to quantify...

Climate change is an increasingly important public health issue, reflected in morbidity and mortality outcomes during extreme heat events. At the same time, the harms of social isolation with respect to a wide range of health outcomes are becoming better understood. Given that older adults are at higher risk during hot weather and at higher risk of...

Previous research has associated snowfall with risk of myocardial infarction (MI). Most studies have been conducted in regions with harsh winters, it remains unclear whether snowfall is associated with risk of MI in regions with milder or more varied climates. This study used a case-crossover design to investigate the association between snowfall a...

There is limited evidence for short-term association between mortality and ambient air pollution in the Middle East and no study has evaluated exposure windows of about a month prior to death. We investigated all-cause non-accidental daily mortality and its association with fine particulate matter (PM2.5), nitrogen dioxide (NO2), and the Air Qualit...

Objective Wildfire smoke is an important source of air pollution associated with a range of cardiopulmonary health conditions. The Air Quality Health Index (AQHI) is the most widely used tool in Canada to communicate with the public about air pollution, but it may not adequately reflect health risks from wildfire smoke. The objective of this study...

In a rapidly urbanizing world, identifying evidence-based strategies to support healthy design is essential. Although urban living offers increased access to critical resources and can help to mitigate climate change, densely populated neighborhood environments are often higher in many of the physical and psychological stressors that are detrimenta...

Urban greenness has been associated with a wide range of health benefits, partially due to local cooling. Several studies on these health benefits have assessed individual and population exposure to urban greenness using the Normalized Difference Vegetation Index (NDVI) from different satellite platforms. Recent comparisons between birds-eye NDVI a...

Objectives To estimate the proportion of the Canadian population that is more susceptible to adverse effects of ozone (O3) and fine particle (PM2.5) air pollution exposure and how this varies by health region alongside ambient concentrations of O3 and PM2.5. Methods Using data from the census, the Canadian Community Health Survey, vital statistics...

The extensible Biomass Smoke Validated Events Database is an ongoing, community driven, collection of air pollution events which are known to be caused by vegetation fires such as bushfires (also known as wildfire and wildland fires), or prescribed fuel reduction burns, and wood heaters. This is useful for researchers of health impacts who need to...

Exposure to wildfire smoke averaged over 24-hour periods has been associated with a wide range of acute cardiopulmonary events, but little is known about the effects of sub-daily exposures immediately preceding these events. One challenge for studying sub-daily effects is the lack of spatially and temporally resolved estimates of smoke exposures. I...

Background: Ambulance data provide a useful source of population-based and spatiotemporally resolved information for assessing health impacts of air pollution in non-hospital settings. We used the clinical records of paramedics to quantify associations between PM2.5 and diabetic, cardiovascular, and respiratory conditions commonly managed by those...

Following an extreme heat event in 2009, a Heat Alert and Response System (HARS) was implemented for the greater Vancouver area of British Columbia (BC), Canada. This system has provided a framework for guiding public health interventions and assessing population response and adaptation to extreme heat in greater Vancouver, but no other parts of BC...