Table 5 BALF cellular and biochemical parameters following repeated exposures to TiO ₂ NPs at different dose rates

Cell viability (%)

95.1 ± 1.4

95.1 ± 2.5

95.0 ± 2.3

94.2 ± 0.8

Total cells (Number ×10 ⁷ )

1.33 ± 0.10

1.17 ± 0.23

1.68 ± 0.06Φ

2.20 ± 0.22*Φ

Alveolar macrophages (%)

98.7 ± 0.4

97.7 ± 0.5

97.9 ± 0.6

81.2 ± 3.8*Φ

(Number ×10 ⁷ )

1.31 ± 0.10

1.14 ± 0.22

1.64 ± 0.06Φ

1.79 ± 0.23

Neutrophils (%)

0.8 ± 0.2

1.6 ± 0.6*

1.2 ± 0.3

16.8 ± 3.6*Φ

(Number ×10 ⁵ )

1.02 ± 0.36

1.96 ± 1.00

2.00 ± 0.60Φ

36.59 ± 6.60*Φ

Lymphocytes (%)

0.6 ± 0.2

0.7 ± 0.2

0.8 ± 0.5

2.1 ± 0.5*Φ

(Number ×10 ⁴ )

7.62 ± 2.25

7.53 ± 2.45

14.05 ± 7.29

45.99 ± 11.86*Φ

LDH release (nmol/min/mL)

46.83 ± 3.72

61.19 ± 4.62*

41.72 ± 3.48

58.81 ± 9.43*

β-Glucuronidase activity (nmol/min/mL)

0.25 ± 0.06

0.25 ± 0.09

0.33 ± 0.09

0.40 ± 0.20

BALF protein (mg/mL) ^a

0.12 ± 0.01

0.15 ± 0.02

0.12 ± 0.01

0.13 ± 0.01