OECD SIDS 5. TOXICITY
ID: 79-50-5 DATE: 18.01.2006
not mate an the 200 mg/ were non-pr female was gestation, were simila
d two females mated in the second mating period. Of kg bw/d dose group, two females egnant. And of the 1000 mg/kg bw/d dose group, one non-pregnant. Mating performance, duration of fertility parameters and number of pups at birth r for the control and treated groups.
Breeding da Breeding pa mg/kg bw/d. check, post
ta rameters were unaffected by treatment up to 1000
The number of dead and living pups at first litter natal loss between days 0-4 post-partum,
living pups similar for
at day 4 post-partum and the viability index were control and treated groups.
Pups Development mg/kg bw/d. and treated
of pups was unaffected by treatment up to 1000 Mean body weights of pups were similar for control groups. Incidental clinical symptoms consisted of
(very) small pups, little or no milk and bruise on the head or snout. Macroscopic examination of the pups revealed tip of tail missing, tip of tail discoloured dark red, autolysis, small appearance and no milk. No relationship with treatment was established for these observations or they were considered to be within the normal biological variation for rats of this age and strain. dl-Lactone from Roche Dalry, batch BX226, purity 99.8% as per certificate of analysis. dl-Lactone was administered by daily oral gavage to male and female Wistar rats at dose levels of 40, 200 or 1000 mg/kg bw/d. The males were exposed for 2 weeks prior to mating, during mating and up to termination (28 days for all males). The females were exposed for 2 weeks prior to mating, during mating, during post-coitum and at least 4 days of lactation. The mean duration of treatment of females was 43 days, with a minimum of 28 days and a maximum of 56 days. Parental toxicity was assessed by observing mortality, clinical signs, body weights, food consumption, functional observations, clinical laboratory investigations, macroscopic examination, organ weights and microscopic examination. At 40 mg/kg bw/d, no parental toxicity was observed. At 200 mg/kg
bw/d, no parental toxicity was observed. At 1000 parental toxicity consisted of clinical symptoms and restless behaviour) in females during days 5 treatment and of increased serum potassium level
mg/kg bw/d, (aggressive to 15 of in males.
Reproductive toxicity was assessed by observing the mating performance, fertility indices and number of pups at birth. No reproductive toxicity was observed up to 1000 mg/kg bw/d. Breeding toxicity was assessed by observing the number of postnatal and breeding loss during lactation. No breeding toxicity was observed up to 1000 mg/kg bw/d. Developmental toxicity was assessed by observing clinical signs, body weights and macroscopic examination of the pups during their lactation period. No developmental toxicity was observed up to 1000 mg/kg bw/d. In conclusion, gavage treatment of male and female Wistar rats with dl-Lactone at dose levels of 40, 200 or 1000 mg/kg bw/d for at least 28 days (during premating, mating, post-coitum and lactation) revealed slight parental toxicity in animals receiving 1000 mg/kg bw/d; this toxicity was transient during