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Repeated dose toxicity

Repeated dose toxicity comprises the adverse general toxicological effects occurring as a result of repeated daily exposure dose to a substance for a specified period up to the expected lifespan of the test species.

The studies yield information on general characteristics of the toxicity, the target organs of toxicity, the dose–response (curve) for each toxicity endpoint, responses to toxic metabolites formed in the organism, delayed responses, cumulative effects, the margin between toxic/non-toxic dose, information on reversibility/irreversibility of the effect, and NOAEL (No Observed Adverse Effect Level), NOEL (No Observed Effect Level) for toxicity.

The repeated dose study is an integral part of the data package produced to perform quantitative risk assessment (QRA) of industrial chemicals, cosmetic ingredients, biocides, pesticides, pharmaceuticals. The point of departure most commonly used for systemic toxicity safety assessment is the NOAEL which is used in the calculation of the MoS (Margin of Safety) or MoE (Margin of Exposure).

The following in vivo repeated dose toxicity tests are available as OECD Test Guidelines:

  • 28-day Oral Toxicity Study in Rodents: OECD test guideline 407
  • 90-Day Oral Toxicity Study in Rodents: OECD test guideline 408
  • 90-Day Oral Toxicity Study in Non-Rodents: OECD test guideline 409
  • Dermal Toxicity: 21/28-day Study (rat, rabbit or guinea pig): OECD test guideline 410
  • Dermal Toxicity: 90-day Study (rat, rabbit or guinea pig): OECD test guideline 411
  • Inhalation Toxicity: 28-Day Study in Rodents: OECD test guideline 412
  • Inhalation Toxicity: 90-day Study in Rodents: OECD test guideline 413
  • Chronic Toxicity Studies in Rodents: OECD test guideline 452

EURL ECVAM validated alternative test methods

Test methods under validation by EURL ECVAM

Development/optimisation/improvement of alternative methods