11 n Journal of Toxicology Table 11: Litter size and viability index of the F2 generation rat pups exposed to SE5-OH during gestation through lactation. 0 n 200 n 2000 Dose (mg/kg/day) n 1000 Number of total oﬀspring at birth Males #8.0 ± 2.8 18 7.9 ± 2.5 18 6.9 ± 1.8 18 6.9 ± 2.9 20 Females 7.0 ± 2.4 18 6.6 ± 2.7 18 6.6 ± 2.2 18 5.5 ± 2.7 20 Total 15.0 ± 1.9 18 14.4 ± 2.2 18 13.5 ± 2.5 18 12.4 ± 4.2 20 (M/F) (144/126) (142/118) (124/119) (137/109) Number of live oﬀspring at birth Males 8.0 ± 2.8 18 7.6 ± 2.6 18 6.9 ± 1.8 18 6.6 ± 3.0 20 Females 6.9 ± 2.3 18 6.4 ± 2.5 18 6.6 ± 2.3 18 5.4 ± 2.8 20 Total 14.9 ± 1.9 18 14.0 ± 2.3 18 13.4 ± 2.5 18 11.9 ± 4.5 20 (M/F) (144/124) (137/115) (124/118) (131/107) Number of live oﬀspring on PND 4 before culling Males 7.8 ± 2.7 18 7.2 ± 3.1 18 6.4 ± 2.1 18 6.4 ± 3.2 19 Females 6.8 ± 2.3 18 6.9 ± 3.0 18 6.3 ± 2.1 18 5.2 ± 3.0 19 Total 14.6 ± 1.8 18 13.2 ± 4.0 18 12.7 ± 2.7 18 11.5 ± 5.0 19 (M/F) (140/122) (130/107) (115/113) (127/103) Number of live oﬀspring on PND 4 after culling Males 3.9 ± 0.6 18 4.2 ± 0.7 17 3.9 ± 0.5 18 3.9 ± 1.0 19 Females 4.1 ± 0.6 18 3.8 ± 0.7 17 4.0 ± 0.6 18 3.4∗ ± 1.0 19 Total 8.0 ± 0.0 18 8.0 ± 0.0 17 7.9 ± 0.2 18 7.4∗ ± 1.3 19 Number of live oﬀspring on PND 21 Males 3.8 ± 0.6 18 4.2 ± 0.7 17 3.8 ± 0.6 18 3.9 ± 1.0 19 Females 4.1 ± 0.5 18 3.7 ± 0.8 17 4.0 ± 0.6 18 3.4 ± 1.0 19 Total 7.9 ± 0.3 18 7.9 ± 0.2 17 7.8 ± 0.5 18 7.4 ± 1.3 19 Viability indexA (%) PND 0 99.23 ± 2.23 18 96.92 ± 4.89 18 99.54 ± 1.96 18 96.21 ± 12.29 20 PND 4 97.91 ± 4.15 18 93.61 ± 23.49 18 94.65 ± 12.02 18 94.43 ± 22.30 19 PND 21 98.61 ± 4.04 18 99.26 ± 3.03 17 98.51 ± 4.34 18 100.00 ± 0.00 19 #Mean ± standard deviation; n = number of litters; PND: postnatal day; Aviability index: PND 0: (number of live oﬀspring born alive/number of oﬀspring born), PND 4: (number of oﬀspring alive on PND 4/number of oﬀspring born alive), PND 21: (number of live weanlings/number of live oﬀspring after culling). of the rat model at the 1000 mg/kg/day dose. From the combined studies herein, we can conclude that in the developmental toxicity phase of the study, a no-observed- adverse-eﬀect-level (NOAEL) for developmental eﬀects of SE5-OH is 2000 mg/kg/day, based on the lack of signiﬁcant embryo-to-fetal stage eﬀect. From the reproductive study, the NOAEL for SE5-OH determined for both male and female rats is 1000 mg/kg/day (6.5 mg equol/kg/day), based on the reduction of body weight, implantations, and live births in the F1 and F2 animals at the 2000 mg/kg/day dose level. Nomenclature ANOVA: Analysis of variance DES: Diethylstilbestrol ER: Estrogen receptor GLP: Good laboratory practice HPMC: Hydroxypropylmethylcellulose MHW: Ministry of Health and Welfare (Japan) NOAEL: No-observed-adverse-eﬀect-level. Acknowledgments All studies described in this manuscript were conducted at Kashima laboratory of the Mitsubishi Chemical Safety Institute, Ltd. (Tokyo, Japan). All studies were sponsored by Tokushima Research Institute of Otsuka Pharmaceutical Co. Ltd. (Tokushima, Japan). References [1] L. Strauss, R. Santti, N. Saarinen, T. Streng, S. Joshi, and S. Ma¨kela¨, “Dietary phytoestrogens and their role in hormonally dependent disease,” Toxicology Letters, vol. 102-103, pp. 349– 354, 1998. [2] J. W. Craig, “Health-promoting phytochemicals: beyond the traditional nutrients,” in Vegetarian Nutrition, pp. 333–348, CRC Press, Boca Raton, Fla, USA, 2001. [3] T. Usui, “Pharmaceutical prospects of phytoestrogens,” Endocrine Journal, vol. 53, no. 1, pp. 7–20, 2006. [4] S. J. Bhathena and M. T. Velasquez, “Beneﬁcial role of dietary phytoestrogens in obesity and diabetes,” The American Journal of Clinical Nutrition, vol. 76, no. 6, pp. 1191–1201, 2002.