2-FUN - Case study no.1

It is now well established that elevated temperatures can lead to increased mortality, and that population vulnerability is location specific. However, very few studies have sought to assess the effects of temperature on daily mortality in urban areas in Portugal.

In order to demonstrate the relevance of the tools developed for health risk assessment within the
2-FUN project, three case studies were conducted.  Case study no.1 aimed to test the tools and datasets provided in other work packages to assess the health effects from heat stress and air pollution in Lisbon. The potential health impacts of future changes in air pollution and thermal stress due to future climate and emission changes were thereby assessed.

The case study was composed of the following sub-studies:

  1. Assessment of the health impact of current and future heat stress.
  2. Acute health effects from particulate matter (PM). PM ranges in size from very small to larger particles. The most commonly measured sizes are PM 2.5 and PM 10. PM 2.5 refers to particles that are 2.5 microns or less in diameter. These particles are extremely small and are therefore more likely to be inhaled deeper into the lungs. PM 10 refers to particles that include 2.5 microns in size as well particles up to 10 microns in diameter, which, because of their relatively larger size, cannot travel as deep into the lungs.
  1. Acute health effects from current and future ozone exposure.
  2. Health risks from ambient BTEX (benzene, toluene, ethylbenzene and xylene) exposures.
  3. Health risks from ambient lead exposures using a full chain study approach.

This study made use of future climate and socioeconomic datasets from other work packages for the first three assessments, and a preliminary version of the project multimedia modelling software for the last two. A generalized estimating equations method was used for modelling the relationship between maximum temperature and daily mortality during the warm season.  

One of the main difficulties when studying future health impacts of climate change is that the resolution of the future climate data is generally too coarse and not suitable for health risk assessment. To evaluate the future impact of heatstress, downscaled future climate scenarios were developed specifically for the region. Another method was used for assessing the number of deaths due to heat exposure, estimating the fraction of annual deaths that could be attributed to maximum temperatures in Lisbon.

Even without extremes in apparent temperature, the project team could observe an association between temperature and daily mortality in Portugal. However, additional research is needed to provide a better assessment of vulnerability within populations in Portugal in order to develop more effective heat-related morbidity and mortality public health programs. Research needs include estimating exposure to temperature extremes, evaluation of efficacy of adaptation measures and improving effectiveness of plans to reduce exposure of population to climate risks.


2- FUN project: newsletter 8 and newsletter 3