Acute toxicity

In vitro acute toxicology:

Skin irritation/corrosion

OECD 431 In vitro skin corrosion: Reconstructed Human Epidermis test method

Study Purpose and Introduction:
The corrosivity potential of a chemical may be predicted by measurement of its cytotoxic effect, as reflected in the MTT assay, on the reconstituted human epidermis. The reconstructed human epidermis closely mimics the biochemical and physiological properties of the upper parts of the human skin and its use for skin corrosivity testing involves the topical application of test materials to the surface of the skin, and the subsequent assessment of their effects on cell viability. This method is approved by international regulatory agencies as a replacement for the identification of corrosives in the in vivo Rabbit skin assay (OECD 404) and is specifically approved as a replacement for the in vivo skin corrosivity test within OECD 431.

study purpose

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 431, “In Vitro Skin Corrosion: Reconstructed Human Epidermis (RhE) Test Method”

OECD 431 In vitro skin corrosion: Reconstructed Human Epidermis test method

study purpose

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 431, “In Vitro Skin Corrosion: Reconstructed Human Epidermis (RhE) Test Method”
h ttps://www.oecd-ilibrary.org/environment/test-no-431-in-vitro-skin-corrosion-reconstructed-human-epidermis-rhe-test-method_9789264264618-en

OECD 439 In vitro skin irritation: Reconstructed Human Epidermis test method

Study Purpose and Introduction:

The irritation potential of a chemical may be predicted by measurement of its cytotoxic effect, as reflected in the MTT assay, on the reconstructed human epidermal model. The reconstructed human epidermis closely mimics the biochemical and physiological properties of the upper parts of the human skin and its use for skin irritation testing involves the topical application of test materials to the surface of the skin, and the subsequent assessment of their effects on cell viability. This method is approved by international regulatory agencies as a replacement for the identification of irritants in the in vivo Rabbit skin assay (OECD 404).

Guidelines and literature:
OECD Guideline for Testing of Chemicals, Section 4, No. 439, “In Vitro Skin Irritation: Reconstructed Human Epidermis Test Methods”
https://www.oecd-ilibrary.org/environment/test-no-439-in-vitro-skin-irritation-reconstructed-human-epidermis-test-method_9789264242845-en

Eye irritation / corrosion

OECD 438 Isolated chicken eye test method for identifying chemicals inducing serious eye damage or chemicals not requiring classification for eye irritation or serious eye

Study Purpose and Introduction:
In the Isolated Chicken Eye Test (ICET) the test item is applied in a single dose onto the cornea of isolated chicken eyes. The purpose of this test is to classify the test item as ocular corrosive and/or severe irritant (UN GHS/CLP Category 1) or to identify the test item as a chemical that does not require classification for eye irritation or serious eye damage under the UN GHS/CLP classification system. The ICET does not fully replace the in vivo rabbit eye test (OECD 405); however, it is used as part of a tiered testing strategy for regulatory purposes.

OECD 438 Isolated chicken eye test method for identifying chemicals inducing serious eye damage or chemicals not requiring classification for eye irritation or serious eye

Guidelines and literature:
Isolated Chicken Eye Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage: OECD test guideline No. 438
https://www.oecd-ilibrary.org/environment/test-no-438-isolated-chicken-eye-test-method-for-identifying-i-chemicals-inducing-serious-eye-damage-and-ii-chemicals-not-requiring-classification-for-eye-irritation-or-serious-eye-damage_9789264203860-en

OECD 492 Reconstructed human Cornea-like Epithelium test method for identifying chemicals not requiring classification and labelling for eye irritation or serious eye damage

Study Purpose and Introduction:

The eye irritation potential of a chemical may be predicted by measurement of its cytotoxic effect, as reflected in the MTT assay, on the EpiOcular™ tissue. The EpiOcular™ can be used to identify chemicals that do not require classification for eye irritation or serious eye damage according to the UN GHS classification system. This test method can be used for partly replacement of the in vivo Rabbit eye test (OECD 405), without the need to use live animals.

oecd 492

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 492, „Reconstructed human Cornea-like Epithelium (RhCE) test method for identifying chemicals not requiring classification and labelling for eye irritation or serious eye damage”
https://www.oecd-ilibrary.org/environment/test-no-492-reconstructed-human-cornea-like-epithelium-rhce-test-method-for-identifying-chemicals-not-requiring-classification-and-labelling-for-eye-irritation-or-serious-eye-damage_9789264242548-en

OECD 492B Reconstructed Human Cornea-like Epithelium Test Method for Eye Hazard Identification

Study Purpose and Introduction:

The eye irritation potential of a chemical may be predicted by measurement of its cytotoxic effect, as reflected in the MTT assay, on the reconstructed Human Cornea Epithelium. The reconstructed Human Cornea Epithelium is designed to closely mimic the histological, morphological, biochemical and physiological properties of the human corneal epithelium. It is a Time-to-Toxicity test. This test method is intended to differentiate between UN GHS No Category, UN GHS Category 1 (serious eye damage) and UN GHS Category 2 (eye irritation).

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 492B, “Reconstructed Human Cornea-like Epithelium (RHCE) Test Method for Eye Hazard Identification”
https://www.oecd-ilibrary.org/environment/test-no-492b-reconstructed-human-cornea-like-epithelium-rhce-test-method-for-eye-hazard-identification_0d603916-en

Phototoxicity

OECD 498 Reconstructed Human Epidermis Phototoxicity test method

Study Purpose and Introduction:

The present assay is designed to detect the phototoxic potential of topically applied chemicals and formulations by using a three-dimensional (3D) human epidermis model. This assay involves application of test materials to the air exposed surface (stratum corneum), mimicking the in vivo situation and allowing for the prediction of the phototoxic potency of test materials applied in usage concentrations. The assay is based on a comparison of the cytotoxicity of a chemical when tested with and without additional exposure to a non-toxic dose of UVA + visible light. Cytotoxicity is determined using the MTT assay which measures the mitochondrial conversion of MTT to formazan.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 498, “In vitro Phototoxicity: Reconstructed Human Epidermis Phototoxicity test method”

OECD 498 Reconstructed Human Epidermis Phototoxicity test method

Study Purpose and Introduction:

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 498, “In vitro Phototoxicity: Reconstructed Human Epidermis Phototoxicity test method”
https://www.oecd-ilibrary.org/environment/test-no-498-in-vitro-phototoxicity-reconstructed-human-epidermis-phototoxicity-test-method_7b2f9ea0-en

Skin sensitization

In vitro skin sensitisation assays are conducted to evaluate the sensitising potential of consumer products like drugs, agricultural chemicals and cosmetics on the Adverse Outcome Pathway.

OECD 442C In Chemico Skin Sensitisation-Assays addressing the Adverse Outcome Pathway key event on covalent binding to proteins

Study Purpose and Introduction:

The purpose of this study is the In Chemico determination of skin sensitization potential (Direct Peptide Reactivity Assay – DPRA) with high-performance liquid chromatography (HPLC) analysis. The DPRA is proposed to address the molecular initiating event of the skin sensitization Adverse Outcome Pathway (AOP), namely protein reactivity, by quantifying the reactivity of the test chemical towards model synthetic peptides containing either cysteine or lysine. Cysteine and lysine peptide depletion values will be then used to categorize the test substance in one of four classes of reactivity for supporting the discrimination between skin sensitizers and non-sensitizers.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 442C, “In Chemico Skin Sensitisation – Assays addressing the Adverse Outcome Pathway key event on covalent binding to proteins”

DB-ALM Protocol n° 154 : Direct Peptide Reactivity Assay (DPRA) for Skin Sensitisation Testing

OECD 442C In Chemico Skin Sensitisation-Assays addressing the Adverse Outcome Pathway key event on covalent binding to proteins

Study Purpose and Introduction:

OECD 442D In Vitro Skin Sensitisation- ARE-Nrf2 Luciferase Test Method

Study Purpose and Introduction:

The purpose of the ARE-Nrf2 luciferase test method (KeratinoSens™) is to contribute to the identification of skin sensitisers and non-sensitisers by addressing the second key event of the skin sensitisation Adverse Outcome Pathway. The KeratinoSens™ method not only supports the discrimination between skin sensitisers from non-sensitisers but, it may also potentially contribute to the assessment of sensitising potency when used in integrated approaches such as the Integrated Approaches to Testing and Assessment (IATA).

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 442D, “In Vitro Skin Sensitisation- ARE-Nrf2 Luciferase Test Method”
DB-ALM Protocol n° 155 : KeratinoSens™

OECD 442E In Vitro Skin Sensitisation- In Vitro Skin Sensitisation assays addressing the Key Event on activation of dendritic cells on the Adverse Outcome Pathway for Skin Sensitisation

Study Purpose and Introduction:

The purpose of the h-CLAT method is to contribute to the in vitro identification of skin sensitisers and non-sensitisers by providing information on the chemical induced expression of cell surface markers CD86 and CD54 in human monocytic leukemia cells (THP-1). The h-CLAT method not only supports the discrimination between skin sensitisers from non-sensitisers but, it may also potentially contribute to the assessment of sensitising potency when used in integrated approaches such as the Integrated Approaches to Testing and Assessment (IATA) or in Defined Approaches (DA) according to OECD 497.

Guidelines and literature:
OECD 442E Guidelines for the Testing of Chemicals, Section 4, No. 442E, “In Vitro Skin Sensitisation- In Vitro Skin Sensitisation assays addressing the Key Event on activation of dendritic cells on the Adverse Outcome Pathway for Skin Sensitisation”
DB-ALM Protocol n° 158 : human Cell Line Activation Test (h-CLAT)

OECD 497 Defined Approaches on Skin Sensitisation

Study Purpose and Introduction:

The in chemico and in vitro test methods (OECD TG 442C, 442D, 442E) addressing the first three key events of the skin sensitisation. None of these test methods are considered sufficient stand-alone replacements in vivo studies or provide information for potency sub-categorisation according to the UN GHS (sub-categories 1A and 1B). The Defined Approaches use method combinations intended to overcome some of the limitations of the individual, stand-alone methods in order to provide increased confidence in the overall result obtained. The ultimate goal of Defined Approaches is to provide information that is equivalent to that provided by in vivo studies, for example information that can be used for hazard identification and/or potency categorisation.

Guidelines and literature:
OECD 497 Guidelines for the Testing of Chemicals, Section 4, No. 497, “Defined Approaches on Skin Sensitisation”

Acute toxicity

In vivo acute toxicology:

Acute oral toxicity

OECD 420 Acute Oral Toxicity - Fixed Dose Procedure

Study Purpose and Introduction:
The objective of the study is to assess the toxicity of test item when administered in a single dose to rats at one or more defined dose levels. The results of the study allow the test item to be ranked according to most classification systems currently in use. The limit test is primarily used in situations where the experimenter has information indicating that the test material is likely to be nontoxic, i.e. having toxicity only above regulatory limit doses.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 420, “Acute Oral Toxicity – Fixed Dose Procedure” (link: https://www.oecd-ilibrary.org/environment/test-no-420-acute-oral-toxicity-fixed-dose-procedure_9789264070943-en)

OECD 420 Acute Oral Toxicity - Fixed Dose Procedure

OECD 423 Acute Oral toxicity - Acute Toxic Class Method

Study Purpose and Introduction:
The test for acute toxicity is performed in the rat. Although several mammalian species may be used, the rat is the preferred rodent species. In the assessment and evaluation of the toxic characteristic of a substance, determination of acute oral toxicity is useful where exposure by the oral route is likely. It provides information on health hazards likely to arise from a short-term exposure by the oral route. Data from an acute oral toxicity study may serve as a basis for classification and labelling.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 423, “Acute Oral toxicity – Acute Toxic Class Method” (link: https://www.oecd-ilibrary.org/environment/test-no-423-acute-oral-toxicity-acute-toxic-class-method_9789264071001-en)

OECD 425 Acute Oral Toxicity: Up-and-Down Procedure

Study Purpose and Introduction:
The test for acute toxicity is performed in the rat. Although several mammalian species may be used, the rat is the preferred rodent species. The aim of this study is to determine the estimated LD₅₀ value and confidence intervals of the test item, following a single oral treatment. This study provides information both for hazard assessment purposes and for hazard classification purposes. Results enable compounds to be ranked in different classification systems.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 425, “Acute Oral Toxicity: Up-and-Down Procedure” (link: https://www.oecd-ilibrary.org/environment/test-no-425-acute-oral-toxicity-up-and-down-procedure_9789264071049-en )

Acute dermal toxicity

OECD 402 Acute Dermal Toxicity

Study Purpose and Introduction:
The objective of the study is to assess the toxicity of test item when administered in a single dermal dose to rats at one or more defined dose levels. This method provides information on the hazardous properties and allows the test item to be classified for acute toxicity according to the Globally Harmonised System of classification and labelling of chemicals.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 402, “Acute Dermal Toxicity” (link: https://www.oecd-ilibrary.org/environment/test-no-402-acute-dermal-toxicity_9789264070585-en)

OECD 402 Acute Dermal Toxicity

Acute inhalation toxicity

OECD 403 Acute Inhalation Toxicity

Study Purpose and Introduction:
This test method provides information on health hazard likely to arise from short-term exposure to a test item (gas, vapour or aerosol/particulate test item) by inhalation.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 403, “Acute Inhalation Toxicity” (link: https://www.oecd-ilibrary.org/environment/test-no-403-acute-inhalation-toxicity_9789264070608-en)

OECD 403 Acute Inhalation Toxicity

OECD 436 Acute Inhalation Toxicity-Acute Toxic Class Method

Study Purpose and Introduction: This method allows hazard assessment for short-term exposure to a test article by inhalation, and allows the substance to be classified according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS).

Guidelines and literature:OECD Guidelines for the Testing of Chemicals, Section 4, No. 436, „Acute Inhalation Toxicity – Acute Toxic Class Method” (link: https://www.oecd.org/en/publications/test-no-436-acute-inhalation-toxicity-acute-toxic-class-method_9789264076037-en.html)

Skin irritation/corrosion

OECD 404 Acute Dermal Irritation/Corrosion

Study Purpose and Introduction:
The main objective of this study is to characterize the possible irritant/ corrosive effects of test item on rabbit’s skin after a single topical application.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 404, “Acute Dermal Irritation/Corrosion” (link: https://www.oecd-ilibrary.org/environment/test-no-404-acute-dermal-irritation-corrosion_9789264242678-en )

OECD 404 Acute Dermal Irritation/Corrosion

Study Purpose and Introduction:
The main objective of this study is to characterize the possible irritant/ corrosive effects of test item on rabbit’s skin after a single topical application.

Eye irritation / corrosion

OECD 405 Acute Eye Irritation/Corrosion

Study Purpose and Introduction:

The main objective of this study is to determine the degree of ocular irritation resulting from the test item introduced in a single dose into the conjunctival sac of the eye of the rabbit.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 405, “Acute Eye Irritation/Corrosion” (link: https://www.oecd-ilibrary.org/environment/test-no-405-acute-eye-irritation-corrosion_9789264185333-en )

OECD 405 Acute Eye Irritation/Corrosion

Study Purpose and Introduction:

The main objective of this study is to determine the degree of ocular irritation resulting from the test item introduced in a single dose into the conjunctival sac of the eye of the rabbit.

Skin sensitization

OECD 406 Skin Sensitisation

Study Purpose and Introduction:
This method provides information on health hazard likely to arise from exposure to test item via intradermical injection and/or epidermical application. The methods preferred over other are: the Guinea Pig Maximisation Test (GPMT) of Magnusson and Kligman which uses adjuvant and the non adjuvant Buehler Test.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 406, “Skin Sensitisation” (link: https://www.oecd-ilibrary.org/environment/test-no-406-skin-sensitisation_9789264070660-en )

OECD 406 Skin Sensitisation

OECD 429 Skin Sensitisation Local Lymph Node Assay

Study Purpose and Introduction:

The aim of this study is to measure the skin sensitizing effect of the test item using the method of Local Lymph Node Assay (LLNA). This assay has been developed as an alternative method for the identification of skin sensitizing substances.

The basic principle underlying the LLNA is that sensitizers induce proliferation of lymphocytes in the lymph nodes draining the site of test substance application (ears). This proliferation is proportional to the dose and to the potency of the applied allergen and provides a simple means of obtaining a quantitative measurement of sensitization. Increased number of proliferating cells in the draining auricular lymph nodes are measured by use of in vivo radioactive labelling.

The ratio of the mean proliferation in a treated group to that in the vehicle control group is termed as Stimulation Index (SI), which should be ≥3 before classification of the test substance as a potential skin sensitizer is warranted.

Guidelines and literature:
OECD Guidelines for the Testing of Chemicals, Section 4, No. 429, “Skin Sensitisation-Local Lymph Node Assay” (link: https://www.oecd-ilibrary.org/environment/test-no-429-skin-sensitisation_9789264071100-en)