Korean J Prev Med.
2001 May;34(2):109-118.
Issues in Air Pollution Epidemiologic Studies
- Affiliations
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- 1Departement of Preventive Medicine, Ewha Womans University College of Medicine.
Abstract
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The purpose of this review is to discuss the debate concerning the interpretation of
epidemiologic studies on particles and health effects. Study of the 1952 air pollution
disaster in London established that very high levels of particulate-based smog can cause
dramatic increases in daily mortality. However, recent epidemiologic studies have
reported statistically significant health effects and mortality due to low levels of air
pollution. The statistical significance does not prove causation in observational studies;
therefore it is necessary to evaluate these associations. There are arguments for and
against each of the numerous studies using Hill's criteria, however the body of
accepted evidence supports the causal association. In particular, a high level of
consistency in the estimated effect of PM10 has been observed across studies worldwide.
The mechanism of the relationship between air pollution and health effects is not
obvious. The mechanism of particle-induced injury may involve the production of an
inflammatory response by the particulate. The harvesting and the threshold effect are
also major concerns regarding the health effects of air pollution. However, current
epidemiologic findings indicate that linear models lacking a threshold are appropriate for
assessing the effect of particulate air pollution on daily mortality even at current levels.