First overview of microplastics in indoor and outdoor air
Johnny Gasperi 1 Rachid Dris 1 Cécile Mirande-Bret 1 Corinne Mandin 2 Valérie Langlois 3 Bruno Tassin 1
1 LEESU - laboratoire Eau, Environnement et Systèmes Urbains
2 CSTB - Centre Scientifique et Technique du Bâtiment
3 ICMPE - Institut de Chimie et des Matériaux Paris-Est
15th EuCheMS International Conference on Chemistry and the Environment, Sep 2015, Leipzig, Germany
https://hal-enpc.archives-ouvertes.fr/hal-01195546
For methodological reasons, the minimal microplastic particle size considered in this study is about 50 µm. For dust, a densimetric separation coupled with an enzymatic digestion was performed. Microplastics observed in indoor and outdoor air are exclusively fibrous with a size distribution. Fibers are mainly sub-millimetric (50-80% between 100 and 500 µm) and to a lesser extent millimetric (10-30% between 500 and 1 000 µm or between 1 000 and 5 000 µm). First campaigns indicate that indoor concentrations are in the 3-15 particles/m3 range. A gradient of indoor concentrations according to the sampling height (30, 125 and 250 cm) was also observed suggesting that the microplastics are mainly re suspended from the floor probably due to human activity and movement. Finally, a significant amount of fibers is observed in dust. Outdoor concentrations are lower than those observed for indoor and are in the 0.2-0.8 particles/m3 range. Due to their size, a high deposition velocity of microplastics may be expected and could explain the low concentrations observed. Parallel to that, a significant amount of particles is also observed in total atmospheric fallout (29-280 particles/m2/d), confirming the contamination of atmospheric compartment by microplastics. The time-variation of this flux seems to be strongly influenced by rain events suggesting that the microplastic wash out could be a major route of deposition. The chemical identification of the microplastics is in progress using Raman micro spectroscopy.
