Two-Generation Reproduction Toxicity Study (OECD TG 416)

942. The OECD Two-Generation Reproduction Toxicity Study is an apical assay designed to provide general information concerning the effects of a chemical on the male and female reproductive systems including gonadal function, the estrus cycle, mating, conception, gestation, parturition, lactation, weaning, and growth and development of the offspring. The rat is the preferred species. The recommended route of administration is oral, via the diet, by gavage or in drinking water. The study is not specifically designed to detect endocrine active substances (EASs), but has many endpoints relevant for the assessment of possible endocrine disruption and provides data on adverse effects related to reproduction and development. OECD TG 416 was revised in January 2001 to include a more comprehensive range of endpoints. These endpoints include sexual maturation (VO and PPS) which are particularly sensitive to EASs. One-generation studies and two-generation studies conducted prior to the adoption of the revised OECD TG 416 are therefore unlikely to provide as much data as studies conducted to the revised OECD TG 416, particularly with respect to endocrine disruption. They do, however, provide a great deal of useful data, particularly on adverse effects on reproduction, that may be sufficient for hazard assessment purposes even if the etiology of the effect(s) is not fully characterised.