Effects of Coarse and Fine Atmospheric Particulate Matter on a Mast Cell Line

Abstract

We investigated the cytotoxicity on a mast cell line (C57 cells) of water-soluble extracts of coarse (>3 µm, PM>3) and fine (0.05–3 µm, PM0.05–3) atmospheric particulates collected from April 2016 to March 2019 in Fukuoka, Japan. We examined the direct cytotoxicity with punched-out membrane filter fragments of PM>3 and PM0.05–3 collected from April 2019 to March 2021, without extraction of the components. Also, cell proliferation and degranulation assays were conducted under conditions which caused no cytotoxicity with water-soluble extracts of PM>3 from FY2016 and PM>3 direct samples from FY2019. The findings revealed the significant direct cytotoxicity of many PM>3 and all PM0.05–3 samples, with higher cytotoxicity for PM0.05–3 (FY2019–2020). These results were different from the cytotoxicity effects of water-soluble extracts of PM>3 and PM0.05–3 samples (FY2016) in previous studies. In addition, inhibition of cell proliferation and induction of degranulation were significantly induced in a few PM>3 samples, showing a correlation with the suspended particulate matter (SPM) concentrations. This method using punched-out membrane filters is convenient and useful for assessing the direct effects of atmospheric particles on a small scale.