Table 1.

Cell viability of lung epithelial A549 cells exposed to outdoor particulate matter with aerodynamic size ≤ 10 µm (PM₁₀) and H₂O₂.

Control	LY294002	PM10+H2O2	PM10+LY+H2O2	H2O2+H2O2	H2O2+LY+H2O2
100	95.23 (SD ± 15.2)	108.8 (SD ± 7.7)	103.7 (SD ± 3.2)	83.3 (SD ± 3.2)	82 (SD ± 7.9)

Control: cells cultured during 24 h with free fetal bovine serum, washed and replaced with fresh cell culture medium, and incubated for a second period of 24 h. LY294002: Cells exposed to 50 µM of LY294002 inhibitor for 48 h. PM₁₀ + H₂O₂: cells exposed to PM₁₀ for 24 h and exposed 500 µM H₂O₂ for 24 h. PM₁₀ + LY + H₂O₂: cells pre-exposed to 10 µg/cm² PM₁₀, incubated with 50 µM LY294002 (inhibitor of PI3K), and treated with 500 µM H₂O₂. H₂O₂ + H₂O₂: cells exposed to 500 µM H₂O₂ during 24 h, washed with cell culture medium and treated again with H₂O₂. H₂O₂ + LY + H₂O₂: cells exposed to H₂O₂ during 24 h and treated with LY294002 and exposed to H₂O₂. The results are the mean ± SD of three independent experiments.