Assessing personal exposure to PM using data from an integrated indoor-outdoor experiment in Athens-Greece

Area of Science:

• Environmental Science
• Public Health
• Atmospheric Chemistry

Background:

• Particulate matter (PM) exposure is a significant public health concern, particularly in urban environments.
• Understanding personal exposure across various microenvironments (MEs) is crucial for assessing health risks.
• Athens, a Mediterranean urban area, faces unique air quality challenges influenced by local emissions and meteorological conditions.

Purpose of the Study:

• To investigate personal exposure to PM10, PM2.5, and PM1 across diverse indoor and outdoor microenvironments in Athens.
• To analyze the chemical composition of PM2.5 and PM1 samples collected during the campaign.
• To identify key sources and activities contributing to indoor and outdoor PM levels and personal exposure.

Main Methods:

• Conducted a 15-day integrated indoor-outdoor PM sampling campaign in central Athens.
• Utilized both stationary (low volume samplers) and portable/wearable instrumentation for continuous PM measurement.
• Collected PM2.5 and PM1 samples for detailed chemical analysis, including OC/EC, ions, and crustal material.

Main Results:

• Residential air quality was influenced by outdoor sources and vertical distance from the street; indoor activities like cooking increased PM levels.
• Outdoor PM2.5 concentrations (11-43 μg/m³) were generally higher than in indoor MEs (e.g., fourth floor: 10-18 μg/m³).
• Highest PM10 exposure occurred in the subway (avg. 218 μg/m³), while cafes with smoking showed maximum PM2.5 (avg. 126 μg/m³) and PM1 (avg. 108 μg/m³); car travel yielded the lowest exposure.

Conclusions:

• Personal PM exposure is highly variable and depends on the specific microenvironment visited and time spent.
• The chemical composition of PM2.5 in Athens is typical of Mediterranean urban areas, dominated by OC/EC, sulfate, and ammonium.
• Effective strategies to reduce personal PM exposure require consideration of both outdoor pollution transport and indoor activities, as well as specific high-exposure MEs like public transport and cafes.