Appendix D - Dossier (PDF) - Tera

date: 20–JUL–2005
5. Toxicity Substance ID: 71–43–2
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corneal injury (i.e. questionable or just perceptible
superficial necrosis in very small areas of the cornea) were
recorded.
Source: BP Chemicals Ltd LONDON
Deutsche Shell Chemie GmbH Eschborn
German rapporteur
Test substance: 99.98% pure.
Flag: Risk Assessment
07–JUL–2005 (1264)
Species: rabbit
Method: other
Year: 1946
Method: Applying a method developed by Carpenter and Smith (Carpenter
and Smyth, 1946), corneal necrosis graded 3 (out of a scale of
10) was reported for benzene. This test method uses 0.005 ml
of the undiluted material which is applied to the center of
the corneas of usually 5 rabbits while the lids are retracted.
About 1 minute later, the lids are released. Eighteen to 24
hours later, the eye is examined and the injury scored
according to a specific scoring system for corneal necrosis.
The individual numerical scores of each eye treated with a
chemical are added together and then divided by the number of
eyes to obtain the score of the injury caused by the
treatment. A score level of 5.0 is selected as representative
of severe injury. This figure corresponds to necrosis, visible
only after staining and covering about 3/4 of the surface of
the cornea; or a more severe necrosis covering a smaller area.
Guided by the result of the scoring after instillation of
0.005 ml of the substance and a table of standardised injury
grades, additional applications are made (using higher volumes
of the substance or using dilutions of the substance) until
the chemical can be assigned to one of the recognised grades
for corneal necrosis.
Result: In a large list of test results is stated for benzene (no data
on purity), that a test according to this Carpenter and Smyth
method revealed corneal necrosis graded 3. Injury grade 3 is
defined as follows: 0.1 ml of the undiluted substances gives
injury of up to 5.0 points or 0.5 ml gives injury over 5.0
points. No data on healing time are documented.
Source: German rapporteur
Flag: Risk Assessment
07–JUL–2005 (1062)
Appendix D: Benzene SIDS Dossier
– 351/957 –