Eye irritation testing of nanomaterials using the EpiOcular™ eye irritation test and the bovine corneal opacity and permeability assay

Table 4 Mean tissue viability of 15 OECD representative nanomaterials determined in the EpiOcular^TM eye irritation test (protocol variant 2, performed with solid test substances only and excluding MWCNT NM-402 ^a)

Test material	TiO₂ NM-100	TiO₂ NM-101	TiO₂ NM-102	TiO₂ NM-103	TiO₂ NM-103	TiO₂ NM-103	TiO₂ NM-104	TiO₂ NM-105	ZnO NM-110	ZnO NM-110	ZnO NM-111	ZnO NM-111	SiO₂ NM-200	SiO₂ NM-200	SiO₂ NM-203	SiO₂ NM-203	CeO₂ NM-211	CeO₂ NM-211	CeO₂ NM-212	MWCNT NM-400	MWCNT NM-401
No. of test run				1^st test run ^b	2^nd test run ^b	3^rd test run ^b			1^st test run ^b	2^nd test run	1^st test run^b	2^nd test run	1^st test run^c	2^nd test run	1^st test run ^c	2^nd test run	1^st test run ^c	2^nd test run
Volume or mass applied	28 mg ^d	22 mg ^d	23 mg ^d	17 mg ^d	17 mg ^d	17 mg ^d	12 mg ^d	6 mg ^d	12 mg ^d	12 mg ^d	25 mg ^d	25 mg ^d	6 mg ^d	6 mg ^d	2.5 mg ^d	2.5 mg ^d	61 mg ^d	61 mg ^d	28 mg ^d	46 mg ^e	32 mg ^e
Viability of tissue #1 relative to NC	108	92	96	30	41	102	89	98	74	63	9	87	127	125	120	81	128	113	113	115	124
Viability of tissue #2 relative to NC	107	97	115	61	80	29	107	121	115	73	131	94	134	95	137	111	131	105	97	106	117
Mean relative tissue viability (and ITV%)	108 (1)	95 (5)	106 (20 ^f)	45 (31)	60 (40)	66 (73)	98 (17)	109 (23 ^f)	94 (40)	68 (10)	114 (34)	91 (7)	131 (7)	110 (30)	128 (17)	96 (30)	129 (3)	109 (8)	105 (16)	111 (9)	120 (7)

The mean tissue viability of 2 tissues / test group is expressed relative to the corresponding negative control (NC) value further indicating (in brackets) the relative inter-tissue variability (ITV%)
^a Protocol variant 2 (performed only with solid test substances): 6 h exposure duration for solids; 25 min post-exposure immersion for solids
^b Repeat of test run due to high variability >20 % (in the case of TiO₂ NM-103: Cessation of testing after 3^rd inconclusive test run)
^c Repeat of test run due to high optical density value (>130 % relative to the NC) of one of the measurements
^d Corresponding to 50 μL bulk volume
^e Corresponding to 2x50 μL bulk volume
^f Even though the ITV% values laid close to the threshold value of 20 %, these test runs were not repeated, since the individual measurements clearly indicated lack of toxicity

ISSN: 1743-8977