Path: Home > GB/T > Page654 > GB/T 21766-2025

Price & Delivery

US$299.00 · In stock · Download in 9 seconds
GB/T 21766-2025: Chemicals - Test method of reproduction/developmental toxicity screening
Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure
Status: Valid

Std ID	Version	USD	Buy	Deliver [PDF] in	Title (Description)
GB/T 21766-2025	English	299	Add to Cart	3 days [Need to translate]	Chemicals - Test method of reproduction/developmental toxicity screening
GB/T 21766-2008	English	279	Add to Cart	3 days [Need to translate]	Chemicals -- Test method of reproduction/developmental toxicity screening

GB/T 21766-2025: Chemicals - Test method of reproduction/developmental toxicity screening

---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/GBT21766-2025
ICS 13.300 CCSA80 National Standards of the People's Republic of China Replaces GB/T 21766-2008 Chemical reproductive/developmental toxicity screening test methods Published on 2025-08-29 Implemented on December 1, 2025 State Administration for Market Regulation The State Administration for Standardization issued a statement.

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1.Structure and Drafting Rules of Standardization Documents". Drafting. This document supersedes GB/T 21766-2008 "Screening Tests for Reproductive/Developmental Toxicity of Chemicals" and is consistent with GB/T 21766-2008. In comparison, aside from structural adjustments and editorial changes, the main technical changes are as follows. ---The time requirements for the trial period have been changed, including the number of days required for different stages. "mating period, pregnancy, and postpartum" (see 4.2.2). 4.2.3 (Chapter 3 of the.2008 edition); ---The requirements for ambient temperature in animal laboratories have been changed (see 5.2.1, 4.1.2 in the.2008 edition); ---The requirements for the number of experimental animals in the experimental process have been changed (see 5.5.1, 5.5.5.1, and 4.2.1 and 4.2.5.1 in the.2008 version); ---Added information on "litter size" (see 5.5.7), "estrous cycle" requirements for selecting female animals (see 5.6.3), and "clinical biochemistry". The requirements for blood sample collection time and thyroid hormone level testing (see 5.6.5), and the requirements for vaginal smears during "gross anatomical examination" The requirements for X-ray examination and weighing of organs such as the prostate and seminal vesicles (see 5.6.6.1); ---The "Results Report" now includes sections on "Thyroid Hormone Levels" and "Number of Adult Female Animals with Normal or Abnormal Estrogenic Cycles and Their Weeks". "Duration of period", "Puppy weight data", "AGD of all pups and weight on the AGD measurement date", "Nipple assessment of male pups" The record of the "situation" (see 6.3). Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents. This document was proposed and is under the jurisdiction of the National Technical Committee on Standardization of Hazardous Chemicals Management (SAC/TC251). This document was drafted by. Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention; Hebei Medical University; and Fujian Ningjiajun Testing. Technical Service Co., Ltd., Ningbo Sansheng Biotechnology Co., Ltd., Ningbo No. 2 Hormone Factory. The main drafters of this document are. Zhang Rong, Pang Yaxian, Bao Lei, Liu Qingping, Li Bin, Chen Xiao, Zhang Hao, Qian Xingyu, and Liu Wei. The release history of this document and the document it replaces is as follows. ---First published in.2008 as GB/T 21766-2008; ---This is the first revision.

introduction

To address the growing need for endocrine disruptor screening in chemical risk assessments, this document is based on GB/T 21766-2008 "Chemicals". This revision, based on the "Screening Methods for Reproductive/Developmental Toxicity of Drugs," adds endocrine-related endpoints, aiming to revise the existing testing guidelines. New guidelines were developed to screen and test for potential endocrine disruptors. The revisions aim to incorporate endocrine-related indicators into the screening guidelines. The exposure period covers certain sensitive periods in development (prenatal or early postnatal). The test substances provided in this document have effects on male and female reproductive processes. Information on the effects of reproductive capacity (such as gonadal function, mating behavior, conception, embryonic development, and delivery) is limited. This document is used in the early stages of chemical hazard assessment, or to provide information on the potential reproductive or developmental effects of chemicals of concern. Preliminary information. For chemicals with almost no toxicological information, it can be used as part of a set of preliminary screening tests to determine bioavailability. Dosage ranges for reproductive/development studies, or in other relevant circumstances. This document pertains to the use of clinical signs as a basis for safety assessment in laboratory animals. The humanitarian end. This document does not provide complete information on all aspects of reproduction/development. It only provides limited means of detecting prenatal exposure. Postpartum effects, or effects that may be induced during postpartum exposure. Due to (among other reasons) the relatively small number of animals in the dose group and the selection of the endpoint. Due to factors such as the limited selection of subjects and the relatively short research period, this document cannot be used as conclusive evidence for determining the absence of reproductive/developmental toxicity. Furthermore, if other biological... Reproductive/developmental toxicity test data, with positive results, can be used for preliminary risk assessment and help determine whether further testing is needed and what tests are required. Schedule. This document provides data on adverse effects on endocrine-related endpoints, but is insufficient to determine whether a test chemical is an endocrine disruptor. Divide the evidence. This document describes the oral route of exposure. If other routes of exposure are used, modifications are required. Chemical reproductive/developmental toxicity screening test methods 1.Scope This document establishes the basic principles for screening chemical reproductive/developmental toxicity, describes the test methods, and specifies the test data. And the contents of the test report. This document applies to tests for the teratogenicity, reproductive toxicity, and developmental toxicity of chemicals.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included. For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies. This document. GB 14925 Laboratory Animal Environment and Facilities 3.Terms and Definitions The following terms and definitions apply to this document. 3.1 androgenicity A chemical substance has the ability to exhibit physiological effects similar to natural androgens (such as testosterone) in mammals. 3.2 Antiandrogenicity The ability of a chemical substance to inhibit or interfere with the effects of natural androgens (such as testosterone) in mammals. 3.3 estrogenicity A chemical substance has the ability to exhibit similar effects to natural estrogens (such as estradiol 17β) in mammals. 3.4 Antiestrogenicity The ability of a chemical substance to inhibit the effects of natural estrogens (such as estradiol 17β) in mammals. 3.5 thyroid activity A chemical substance has the ability to behave like a natural thyroid hormone (such as triiodothyronine, T3) in mammals. 3.6 Antithyroid activity The ability of a chemical substance to inhibit the action of natural thyroid hormones (such as T3) in mammals. 3.7 Abnormalities occur in the reproductive function or ability of female or male animals. 3.8 Structural (organismic defects) or functional abnormalities exhibited by offspring before birth, during the perinatal period, and after birth. 3.9 dose The quantity of the test substance used in the test. 3.10 Dosage The term encompasses the dosage, frequency, and duration of exposure to a substance. 3.11 obvious toxicity Symptoms of poisoning that can be observed or detected after administration of the test substance. 3.12 No-observed-adverse-effect level (NOAEL) No maximum dose of harmful effects related to toxicity was found in the test subjects. 3.13 Reproduction toxicity The harmful effects of the agent on offspring and the damage to male and female reproductive function or capacity. 3.14 Validation To clarify the operational requirements and limitations of the testing method and to demonstrate its reliability and applicability in specific application scenarios, a scientific approach is needed. process. 4.Basic Principles of the Experiment 4.1 Based on the sex of the test subjects (male and female), multiple dosage groups were established for administration of the test substance. The exposure period for male animals was at least [duration missing] until sacrifice. Four weeks, meaning at least two weeks of exposure before mating, and approximately two weeks during and after mating. This is because male animals are exposed to the virus relatively longer before mating. Short reproductive capacity cannot be used as a specific and sensitive indicator of testicular toxicity; therefore, a detailed histological examination of the testes is important. Through staining... Observation of mating behavior/reproductive capacity in male animals during the toxic period, and subsequent detailed histopathological examination of the male gonads, can detect... It exhibits major toxic effects on male fertility and sperm formation. 4.2 Female animals were exposed to the drug throughout the entire experimental period. The experimental period included two weeks prior to mating (comprising at least two complete estrus cycles) and mating. During the period of pregnancy, gestation, and at least 13 days after delivery, up to the day before execution. 4.3 After the adaptation period, the duration of the trial depends on the toxic effects observed in the female animals. The trial period is approximately 63 days, i.e., at least before mating. The mating period lasts about 14 days, while the gestation and lactation periods last about 22 days and 13 days respectively. 4.4 During the exposure period, observe the animals' toxic effects daily. Perform autopsies on all animals that die or are euthanized during the experiment. End of experiment. At that time, all surviving animals were euthanized and dissected. 5.Test Methods 5.1 Animal Selection The test animals used in this experiment were rats. If other animal species are used, the conditions need to be modified accordingly. Avoid using animals with low reproductive rates and... ...