A brief about OECD test guideline 435 , commercially called as Corrositex, This test deals with In vitro test for testing of chemicals classified under GHS category.
2. • In vitro membrame barrier
test for skin corrosion
• Tested for chemicals listed
under GHS category 1
• To identify corrsive chemicals
making irreversible damage to
skin followed by necrosis
INTRODUCTION
OECD
TEST
GUIDELINE
435
OECD 435 - https://www.oecd-ilibrary.org/environment/test-no-435-in-vitro-membrane-barrier-test-method-for-
skin-corrosion_9789264242791-en
3. CONTINUED……….
● Traditionally it was assessed by applying onto
the skin of living animals
● OECD TG 404 In vivo rabbit skin procedure
(irreversible)
● IATA (Integrated approach for testing and
assessments) for skin in vitro tests for skin
irritation and skin corrosion potential
chemicals
MOTO
• Reducing and refining use of animals
• Avoiding pain and distress for animals
4. CORROSITEX
Validated test that determines
chemical corrosivity and permits
assingnment of GHS category
classification of class 8
corrosives
5. Class of chemicals
01 02 03 04
Acids,inorganic
and organic
Acid
derivatives
Acyl halides
Alkylamines
Polyalkylami
nes
Chlorosilanes
Metal halides
Oxyhalides
6. The UN GHS Skin Corrosive Category and
Subcategories
11. ● This test method detects
via the CDS membrane
barrier damage caused by
corrosive test chemicals
after the application of the
test chemical to the
surface of the synthetic
macromolecular
membrane barrier ,
resembling the same
mechanisms of corrosion
that operate on living skin.
BIO
BARRIER ?
CDS ?
CORROSITEX
12. Penetration of the
membrane barrier
(or breakthrough)
might be measured
by a number of
procedures or CDS,
including a change
in the color of a pH
indicator dye or in
some other property
of the indicator
solution below the
barrier.
The membrane
barrier should
be determined
to be valid that
is relevant and
reliable for its
intended use .
FEATURES
PENETRATION MEMBRANE
13. composed of protein,
keratin, collagen, or
mixtures of proteins,
forming a gel matrix,
serves as the target for
the test chemical
The permeable supporting
membrane provides
mechanical support to the
proteinaceous gel during
the gelling process and
exposure to the test
chemical. The supporting
membrane should prevent
sagging or shifting of the gel
and be readily permeable to
all test chemicals.
Proteinaceious
macromolecular
aqueous layer
Permeable supporting
membrane
Components of membrane barrier
14. The fully constructed membrane barrier should be stored under
pre-determined conditions shown to preclude deterioration of the
gel, e.g., drying, microbial growth, shifting, cracking, which would
degrade its performance. The acceptable storage period should
be determined and membrane barrier preparations not used after
that period.
15. PROCEDURE FOR TEST
Compatibility test is
performed to determine if
the test chemical is
detectable by the CDS.
02
Test chemical time
scale category test
03 Membrane barrier
04
Chemical detection
system (CDS)
01
16. • Established time parameters for each of the UN GHS corrosivity Sub-categories, the time
(in minutes) elapsed between application of a test chemical to the membrane barrier and
barrier penetration is used to predict the corrosivity of the test chemical
• positive control should give the expected penetration response time
• negative control should not be corrosive, and, when included, the concurrent solvent
control should neither be corrosive nor should it alter the corrosivity potential of the test
chemical.
Study Acceptability criteria
17. Results
• The time (in minutes) elapsed between application of the test chemical to the membrane
barrier and barrier penetration is used to classify the test chemical in terms of UN GHS
corrosive Sub-categories.
• Cut-off time values for each of the three corrosive subcategories are established for each
proposed test method.
• Final decisions on cut-off times should consider the need to minimize under-classification of
corrosive hazard ( i.e., false negatives
