Acute dermal toxicity – OECD 402 test

Test 402 , entitled Acute Skin Toxicity , is a regulatory toxicology study designed to assess the effects of a substance or mixture when applied directly to the skin. Performed in accordance with OECD guidelines and the principles of Good Laboratory Practice (GLP) , this test is essential for determining the toxic potential of a product after a single skin exposure.

OECD 402 Test Objectives

The study allows us to:

• Determine the cutaneous LD50 (lethal dose 50), that is, the dose causing mortality in 50% of the animals tested.
• Identify local or systemic effects related to skin absorption.
• Classify substances according to toxicological classification systems (e.g. CLP in Europe, GHS internationally).
• Providing essential data for regulatory dossiers (REACH, biocides, plant protection products, cosmetics, industrial chemicals).

Methodology and procedure of the trial

The test is performed in a laboratory according to a standardized protocol:

• Animal species : usually the rat, considered as a reference model.
• Route of administration : application of the tested substance directly onto shaved skin, often covered with an occlusive dressing to prevent accidental ingestion.
• Duration of exposure : 24 hours, followed by a 14-day observation period.
• Observed parameters : clinical signs of toxicity, body weight, mortality, local skin effects (erythema, irritation, necrosis).
• Expected results : determination of the cutaneous LD50 and classification of the substance.

Applications and sectors concerned

The OECD 402 test is essential for several industries subject to strict regulatory requirements:

• Chemical industry : classification and labelling of substances.
• Biocides and plant protection products : registration and placing on the market.
• Cosmetics : safety assessment of ingredients (alternative and scientific justification for skin data).
• Pharmaceuticals : development and control of new molecules.
• Agri-food and packaging : verification of potential auxiliary substances or residues.

Regulatory compliance and associated standards

The OECD 402 test meets the requirements of the main regulatory frameworks:

• REACH Regulation (EC 1907/2006) : registration of chemical substances in Europe.
• CLP Regulation (EC 1272/2008) : classification, labelling and packaging of chemicals.
• Biocidal Products Regulation (BPR, EU 528/2012) : toxicological assessment for marketing authorization.
• OECD Guidelines : international standardization to ensure comparability of results.

Challenges for manufacturers

Taking this test allows companies to:

• Comply with legal obligations for registration and marketing.
• Ensuring the safety of users and consumers.
• Assess the occupational risks for exposed workers.
• Avoid regulatory penalties related to incomplete or non-compliant files.

YesWeLab support for your OECD 402 tests

GLP- compliant laboratories perform the OECD 402 test in strict accordance with international guidelines.

With YesWeLab, you benefit from:

• A selection of the laboratory best suited to your needs (type of substance, regulatory framework).
• Personalized scientific support to define the testing conditions.
• Digital monitoring of your projects via our platform.
• results recognized by regulatory authorities.

Related analyses

• OECD 401 – Acute oral toxicity
• OECD 403 – Acute inhalation toxicity
• OECD 404 – Skin irritation/corrosion
• OECD 405 – Irritation/Eye
• OECD 429 – Skin sensitization
• OECD 407 – Subchronic toxicity studies
• OECD 452 – Chronic Toxicity Studies OECD 452