Table 4.

Overview of TiO₂ intratracheal instillation data from studies in the literature using some of the dispersion media also investigated in the current study

Animal species	TiO2 size (nm)	Form	Coating	Dispersion medium	Doses	Inflammation (BAL neutrophil increase) at 24 h	DNA damage in BAL cells	Reference
Mouse	10	Rutile (same as NRCWE-001)	None	Water	18, 54 and 162 µg/ mouse	Yes, at two highest doses	BAL cells: no effect (increasing at two lowest doses at 3 days only tail length)	(60)
Mouse	10	Rutile (same as NRCWE-002)	Positively charged (amino-TiO2)	Water	18, 54 and 162 µg/ mouse	Yes, at two highest doses	BAL cells: decreased tail length 24 h but increased at highest dose at 3 days (tail length and tail percentage)	(60)
Mouse	288	Rutile	Al and polyalcohol	10% BAL in NaCl	54 µg/mouse	No	BAL cells: yes	(06)
Mouse	20.6	Rutile	Si, Al, Zr, polyalcohol	10% BAL in NaCl	54 µg/mouse	Yes	BAL cells: yes	(06)
Mouse	19	7.8% rutile/92% anatase	None	10% BAL in NaCl	54 µg/mouse	Yes	BAL cells: no	(06)
Mouse	10	Rutile (same as NRCWE-002)	Positively charged (amino-TiO2)	Water	8, 32, 64 or 128 µg/ mouse	Yes, at highest dose	Not measured	(09)
Mouse	10	Rutile (same as NRCWE-002)	Positively charged (amino-TiO2)	2% serum	8, 32, 64 or 128 µg/ mouse	Yes, at two highest doses	Not measured	(09)
Rat	15	‘Clear crystalline form’	Not reported	Water	0.2 (0.66 mg/kg bw) or 1 mg (3.3 mg/kg bw)	Yes, at the highest dose	Not measured, but no lung tumours at 24 months	(72)
Rat	15	Anatase	None	Water	1 mg/rat	No, but only tested at 3 days	Not measured	(73)
Rat	14	Rutile	None	Water	1 mg/rat	No, but only tested at 3 days	Not measured	(73)
Rat	14	Amorphous (anatase crystallite size 6.1)	Not reported	Water	1 mg/rat	Yes, but only tested at 3 days	Not measured	(73)
Rat	28	P25 (anatase crystallite size 23.5 and rutile crystallite size 35.9 nm)	Not reported	Water	1 mg/rat	Yes but only tested at 3 days	Not measured	(73)