OECD TG 414 is the “Prenatal Developmental Toxicity Study” standard, which is included in Section 4 (Health Effects) of the OECD Test Guidelines for the Testing of Chemicals. The test aims to evaluate the effects of a test substance on embryonic and fetal development in pregnant animals. The study allows for the simultaneous investigation of maternal toxicity, embryo-fetal toxicity, and teratogenic potential.
The basic principle of the test is to administer the test substance during the stage of pregnancy that includes organogenesis and to examine the fetuses toward the end of pregnancy via cesarean section.
Rats are generally used; depending on regulatory requirements, a second animal species, such as rabbits, may be preferred. The route of administration, dosages, and duration of treatment are determined based on the physicochemical properties of the test substance and the expected route of exposure.
The main parameters evaluated in the study are as follows:
Maternal parameters:
Clinical observations, body weight, and feed intake
- Pregnancy Rate and Uterine Weight
- Indicators of Maternal Toxicity
Embryonic and fetal parameters:
- Number of corpus luteums, number of implantations
- Number of live, dead, and resorbed fetuses
- Fetal Body Weight and Sex Ratio
- Physical Examination: Malformations and Abnormalities
- Visceral Examination: Abnormalities of the Internal Organs
- Skeletal Examination: Bone Malformations and Abnormalities
The primary purpose of the test is to scientifically evaluate the relationship between maternal toxicity and embryo-fetal development, as well as to determine the developmental toxicity potential of the test substance.
The study design includes a negative control group, a solvent control group, and, if applicable, a positive control group; the dose levels and group sizes are justified in accordance with the regulatory requirements of OECD TG 414.
Why is the test performed?
OECD TG 414 is being conducted for the following scientific and regulatory purposes:
- Assessment of Developmental Toxicity: Identification of Adverse Effects of the Test Substance on Embryonic and Fetal Development
- Assessment of Teratogenic Potential: Identification of Structural Malformations and Developmental Abnormalities
- Evidence of a link to maternal toxicity: Scientific interpretation of whether the observed embryo-fetal effects are independent of maternal toxicity
- Support for Regulatory Documentation: Use in the Safety Assessment of Drugs, Chemicals, Pesticides, Biocidal Products, Medical Devices, and Biotechnology Products
- Approach to Evidential Weight: A Contribution to Risk Assessment in Conjunction with Other Toxicity Data, Physicochemical Properties, and Exposure Assessment
- Product Safety and Quality Assurance: Documentation of the biosafety profile of raw materials, intermediates, or finished products
OECD Guideline TG 414 does not cover the entire reproductive toxicity profile. Fertility, early embryonic development, and postnatal development are evaluated in separate tests. The results should be interpreted in conjunction with the relevant regulatory guidelines and other data on reproductive toxicity.
As part of our nano-testing services, we conduct tests in accordance with OECD TG 414 with scientific rigor, leveraging our accredited laboratory infrastructure and quality management system. Our scope of services includes the following:
Study Design and Protocol Development
- Preparation of a test report in accordance with OECD TG 414
- Determination of the dosage range and establishment of the main experimental design based on the physicochemical properties of the test substance
- Establishment of negative controls, solvent controls, and, where appropriate, suitable positive control groups
- Scientific rationale for the selection of species, route of administration, dosage levels, and duration of administration
- Compliance with Ethical Review and Animal Welfare Requirements
For your studies under OECD TG 414, you can contact Nano-Test to obtain information on study design, species selection, sample acceptance criteria, the testing schedule, and reporting procedures. We will develop a customized study plan for you that is tailored to the physicochemical properties of the test substance and your regulatory objectives.