title: An analysis of the results from Two-Generation Reproduction Toxicity Studies to assess the value of mating animals of the second (F1) generation for the detection of adverse treatment-related effects on reproductive performance.
abstract: The need to routinely perform a two-generation study to assess reproductive performance is under debate. This review has analysed the results from 22 consecutive Two-Generation Reproduction Toxicity Studies performed within our laboratories, to determine the value of mating each generation in the detection of treatment-related effects on reproductive performance. The chemicals included 13 agrochemicals, 5 industrial chemicals and 4 food additives. Four chemicals (all from the agrochemical group) were found to have clear treatment-related effects and in three studies effects were confined to the second (F1) generation. For the three studies with second (F1) generation effects, we applied the triggers, proposed by the Agricultural Chemical Safety Assessment (ASCA) Technical Committee of HESI, for extension of the one-generation study and found that mating of the second (F1) generation would have been triggered in these studies by effects on the F1 offspring growth and sexual maturation. No effects were seen in the original parental (F0) generation which would have activated the change from a one- to a two-generation study.
authors.affiliation: Huntingdon Life Sciences, Eye, Suffolk IP23 7PX, UK. MyersD@ukorg.huntingdon.com
authors.forename: David P
authors.initials: DP
authors.lastname: Myers
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Willoughby
authors.forename: Audrey M
authors.initials: AM
authors.lastname: Bottomley
authors.forename: Jochen
authors.initials: J
authors.lastname: Buschmann
mesh_terms: D016573:Agrochemicals / Q000633:toxicity*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D051381:Rats; D015203:Reproducibility of Results; D012098:Reproduction / Q000187:drug effects*; D012107:Research Design; D012741:Sexual Maturation / Q000187:drug effects; D036401:Toxicity Tests, Chronic / Q000379:methods*
chemical_list: D016573:Agrochemicals