Cell count in bronchoalveolar lavage fluid. The effect of titanium dioxide (TiO2) inhalation exposure performed for 2 hours a day, three days a week, for four weeks at a concentration of 10 mg/m3 on macrophage, eosinophil, neutrophil and lymphocyte infiltration to bronchoalveolar lavage fluid (BALF) calculated from May-Grünwald-Giemsa (MGG)-stained cytospin slides with light microscopy (x80). Results are shown as cells per high power field (HPF) for healthy (PBS) and allergic (OVA) mice exposed to nanosized (nTiO2) or fine (fTiO2) TiO2 or left unexposed (-). From each slide the cells were counted from three fields from which an average was counted. N = 8 mice per group. The bars represent mean ± SEM; * P < 0.05 and ** P < 0.01 significantly different from unexposed control; Mann-Whitney U test.