Table 3. Validity Check by In Vivo-Measured Clearance,^54,69−72 which Is Converted to the Contribution of Dissolution to Clearance, which Is Then Compared to the Measured Dissolution Halftimes (t1/2) from CFS Dissolution in the pH 4.5 PSF Medium^a.

	derivation of t1/2dissolution (days) from in vivo studies				t1/2dissolution (days) measured by CFS in different pH 4.5 fluids
ENM	%	source of in vivo clearance	t1/2in vivo (days)	t1/2dissolution (days) calculated from in vivo	PSF	C: MK (phthalate)	D: MG (citrate)	E: MG (HCl)	Muhle	Midander	Shinohara
CeO2 NM-212	5% cleared per 21d (STIS)	141CeO2 instillation, Molina et al.72	140	no contribution of dissolution (>1000)	2001	4371	5998	1252	4567	3610
TiO2 NM-105		TiO2 P25 inhalation, Bermudez et al.69	70 to 300 (biphasic)	no contribution of dissolution (>1000)	714	2441	840	2155	149 *	89 *
SiO2 NM-200	39% cleared per 21d (STIS)	STIS on SiO2 untreated, Landsiedel et al.71	29	50	31.4	16.6	11.5	15.3	16.9	5.7 *
BaSO4 NM-220		from 131BaSO4 instillation, Konduru et al.54	9.6	11.1	6.3	9.1	9.2	7.5	10.5	3.2 *	0.9 *
ZnO NM-111	>93% cleared per 21d (STIS)	STIS, Landsiedel et al., 2011	<5.4	<5.9	0.88	0.31	0.27	1.38	0.24	0.37

^aFrom the study of Bermudez et al.,⁶⁹ the results obtained at 2 mg/m³ (below lung overload) were evaluated. The tested-grade TiO₂ P25 is nearly identical with the physical–chemical properties of the specific batch known as TiO₂ NM-105.⁶⁹ All CFS results that deviate by more than a factor of 2 from the derived in vivo halftime are underlined in black and those that are considered as severe conflict are marked by an asterisk.