Determining repeated dose toxicity and reproductive/developmental toxicity of <i>cis</i>-3-hexenyl salicylate and comparing salicylate-induced toxicity

Cis3-hexenyl salicylate (HS) is a fragrance ingredient and specified as an existing substance, which was on the market before the Chemical Substance Control Law (CSCL) was established in Japan. Because the toxicity of HS was unknown, the combined repeated dose toxicity study with the reproductive/developmental toxicity screening test of HS was conducted according to the organization for economic co-operation and development (OECD) TG 422 for screening assessment under the CSCL. Male and female rats were administered HS at 0 (control: corn oil), 40, 120, and 360 mg/kg bw/day for 42 and 41–49 days, respectively. Deaths were observed in three dams on the day of delivery or after delivery at 360 mg/kg bw/day. HS exerted hematological effects indicating anemia or weakened blood clotting at 360 mg/kg bw/day in both sexes, which might be related to the dams’ death. HS may be hydrolyzed as salicylic acid, a known prostaglandin synthesis inhibitor, and cis-3-hexenol. Oral dosing of HS at 360 mg/kg bw/day exerted toxicological effects probably mediated by decreased prostaglandin levels, which included weakened blood clotting, indicative kidney injury, glandular stomach erosion, increased trabecular bone formation in the femoral bone, and prolonged gestation length. HS also exerted adverse effects on reproduction at 360 mg/kg bw/day, decreasing the gestation index and number of liveborns. Moreover, delivered pups exhibited decreased body weights on postnatal days 0 and 4 and malformations such as exencephaly and spinal rachischisis at the same dose. Therefore, the no-observed-adverse-effect level was determined as 120 mg/kg bw/day for both repeated dose general toxicity and reproductive/developmental toxicity.