Are the Health Effects of PM_2.5 Derived from Specific Components?

Novel Epidemiological Findings Using Emergency Ambulances as a Health Impact Indicator

Dr. Takehiro Michikawa of the Department of Environmental and Occupational Health, Toho University Faculty of Medicine, and his research group from other universities and institutes focused on the components of fine particulate matter (PM_2.5), an air pollutant with known health effects, and examined whether fluctuations in the concentration of these components are associated with the number of emergency medical evacuations due to sudden illnesses. This is the first epidemiological study to statistically analyze the relationship between PM_2.5 components and emergency transport. It reported that an increase in the concentration of certain components may increase acute illnesses requiring emergency transport, the health impact indicator used in this study.

The results were published in Environmental Science & Technology on May 24, 2022.

Key points:

First analysis of the relationship between PM_2.5 and the number of emergency transports, focusing on its constituents.
The number of emergency medical evacuations increased with an increase in the average carbon concentration on the day of the evacuation and the day before.
It is necessary to deepen our understanding of the health effects of PM_2.5 components in the future.

Background of the research:
Fine particulate matter (PM_2.5), a type of air pollutant consisting of particles of 2.5 μm (1 μm is 1/1,000 of 1 mm) or less suspended in the atmosphere, is thought to cause respiratory and cardiovascular diseases. So far, research results have mainly been accumulated on the overall concentration of PM_2.5 and its effects on health. Additionally, since PM_2.5 is a mixed substance consisting of multiple components (carbon components, ionic components such as sulfate and nitrate ions, inorganic elemental components such as iron and aluminum, etc.), research is being conducted to determine whether the health effects of PM_2.5 are caused by specific components. There are still fewer epidemiological studies on the relationship between the concentration of PM_2.5 components and human health, compared to studies on the total mass concentration of PM_2.5. A research group consisting of Toho University, Keio University, the National Institute for Environmental Studies, the Tokyo Metropolitan Research Institute for Environmental Protection, and Hokkaido University used data on emergency medical care evacuations, which are indicators of acute illnesses and symptoms, and investigated whether daily fluctuations in the concentrations of specific PM_2.5 components are related to the number of emergency medical care evacuations.

Journal
Environmental Science & Technology: May 24, 2022 issue

Title
A case-crossover analysis of the association between exposure to total PM_2.5 and its chemical components and emergency ambulance dispatches in Tokyo

Authors
Michikawa T*, Sasaki J, Yamazaki S, Takami A, Asakura K, Imamura H, Ueda K, Saito S, Hoshi J, Yoshino A, Sugata S, Nitta H, Nishiwaki Y.

DOI Number
10.1021/acs.est.1c08219