ERF of PM2.5 on mortality in general population

From Testiwiki
Revision as of 06:48, 19 September 2011 by Pauliina (talk | contribs) (See also)
Jump to: navigation, search


Scope

ERF of PM2.5 on mortality in general population describes the relationship between PM2.5 exposure and specific causes of mortality in general adult population. The variable focuses but is not limited to long-term (chronic) exposure.

Definition

Data

PM2.5 are fine particles less than 2.5 μm in diameter. Exposure-response function can be derived from exposure modelling, animal toxicology, small clinical or panel studies, and epidemiological studies. Exposed population can be divided into subpopulations (e.g. adults, children, infants, the elderly), and exposure is assessed per certain time period (e.g. daily or annual exposure).

  • Health effects related to short-term exposure
    • respiratory symptoms
    • adverse cardiovascular effects
    • increased medication usage
    • increased number of hospital admissions
    • increased mortality
  • Health effects related to long-term exposure (more relevance to public health)
    • increased incidence of respiratory symptoms
    • reduction in lung function
    • increased incidence of chronic obstructive pulmonary disease (COPD)
    • reduction in life expectancy
      • increased cardiopulmonary mortality
      • increased lung cancer mortality

Sensitive subgroups: children, the elderly, individuals with heart and lung disease, individuals who are active outdoors.


Mortality effects of long-term (chronic) exposure to ambient air

In principle the ERFs for long-term exposure (produced by cohort studies) should also capture the mortality effects of short-term exposure (ERFs produced by time-series studies). In practice it is likely that they do not do so fully. This is due to the so-called "harvesting" phenomenon, i.e. it is possible that acute exposure, at least to some extent, only brings forward deaths that would have happened shortly in any case. However, adding effects of acute exposure to effects of long-term exposure is problematic because the risk of double-counting. [1]

Pope et al. (2002) [2]

  • 6% increase in the risk of deaths from all causes (excluding violent death) (95% CI 2-11%) per 10 µg/m3 PM2.5 in age group 30+
  • 12% increase in the risk of death from cardiovascular diseases and diabetes (95% CI 8-15%) per 10 µg/m3 PM2.5 in age group 30+
  • 14% increase in the risk of death from lung cancer (95% CI 4-23%) per 10 µg/m3 PM2.5 in age group 30+

Woodruff et al (1997) [3]

  • 4% (95% Cl 2%-7%) increase in all-cause infant mortality per 10 µg/m3 PM10 (age 1 month to 1 year)


'Mortality effects of short-term (acute) exposure to ambient air PM

Anderson et al. 2004 [4]

  • 0.6% (95% Cl 0.4%-0.8%) increase in all-cause mortality (excluding accidents) per 10 µg/m3 PM10 in all ages
  • 1.3% (95% Cl 0.5%-2%) increase in respiratory mortality per 10 µg/m3 PM10 in all ages
  • 0.9% (95% Cl 0.5%-1.3%) increase in cardiovascular mortality per 10 µg/m3 PM10 in all ages

Unit

Relative risk (RR) per 10 µg/m3 increase in exposure

Result

ERF for chronic PM2.5 exposure

Cause of death RR 95% Cl
All-cause 1.06 1.02-1.11
Cardiopulmonary 1.09 1.03-1.16
Lung cancer 1.14 1.04-1.23

See also

References


<mfanonymousfilelist></mfanonymousfilelist>