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Your Environment. Your Health.

Climate Change and Human Health Literature Portal Spatiotemporal influence of temperature, air quality, and urban environment on cause-specific mortality during hazy days

Climate Change and Human Health Literature Portal

Ho HC, Wong MS, Yang L, Shi W, Yang J, Bilal M, Chan TC
Environment International. 112: 10-22

Haze is an extreme weather event that can severely increase air pollution exposure, resulting in higher burdens on human health. Few studies have explored the health effects of haze, and none have investigated the spatiotemporal interaction between temperature, air quality and urban environment that may exacerbate the adverse health effects of haze. We investigated the spatiotemporal pattern of haze effects and explored the additional effects of temperature, air pollution and urban environment on the short-term mortality risk during hazy days. We applied a Poisson regression model to daily mortality data from 2007 through 2014, to analyze the short-term mortality risk during haze events in Hong Kong. We evaluated the adverse effect on five types of cause-specific mortality after four types of haze event. We also analyzed the additional effect contributed by the spatial variability of urban environment on each type of cause-specific mortality during a specific haze event. A regular hazy day (lag 0) has higher all-cause mortality risk than a day without haze (odds ratio: 1.029 [1.009, 1.049]). We have also observed high mortality risks associated with mental disorders and diseases of the nervous system during hazy days. In addition, extreme weather and air quality contributed to haze-related mortality, while cold weather and higher ground-level ozone had stronger influences on mortality risk. Areas with a high-density environment, lower vegetation, higher anthropogenic heat, and higher PM2.5 featured stronger effects of haze on mortality than the others. A combined influence of haze, extreme weather/air quality, and urban environment can result in extremely high mortality due to mental/behavioral disorders or diseases of the nervous system. In conclusion, we developed a data-driven technique to analyze the effects of haze on mortality. Our results target the specific dates and areas with higher mortality during haze events, which can be used for development of health warning protocols/systems.

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Resource Description

    Air Pollution, Extreme Weather-Related Event or Disaster, Temperature
    • Air Pollution, Extreme Weather-Related Event or Disaster, Temperature: Interaction with Temperature, Particulate Matter
    • Air Pollution, Extreme Weather-Related Event or Disaster, Temperature: Cold, Heat
    Non-United States
    • Non-United States: Asia
    Mental Health and Well-Being, Morbidity/Mortality, Neurological Impact
    • Mental Health and Well-Being, Morbidity/Mortality, Neurological Impact: General Mental Health and Well-Being
    Research Article
    Vulnerable Population
    • Vulnerable Population: Other Vulnerable Population, Specify
      • Other Vulnerable Population, Specify: Pre-existing Medical Condition
      Other Vulnerable Population, Specify
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