OECD SIDS 5. TOXICITY
ID: 79-50-5 DATE: 18.01.2006
257568 (Determination of the hydrolysis of dl-lactone as a function of pH) it was determined that dllactone was hydrolytically stable at pH 4 and 50ºC. Formulations in Milli-Q water are stable for 4 hours at room temperature and formulations in Milli-Q water adjusted to pH 4 are stable for 4 hours at room temperature and for 8 days at 37°C (determined during this project).
Animal husbandry Conditions. A controlled environment was maintained in the room with optimal conditions of approximately 15 air changes per hour, a temperature of 17.1-24.2°C, a relative humidity of 33-76% and a 12 hour light/12 hour dark cycle. Temporary deviations from the maximum level for relative humidity (with a maximum of 6%) and light/dark cycle (with a maximum of 1 hour) occurred due to cleaning procedures or performance of functional observations in the room. Based on laboratory historical data these deviations are considered not to affect the study integrity.
Accommodation Upon arrival, animals were housed in groups of 5 animals/sex/cage in suspended stainless steel cages. During the mating procedures, females were caged together with males on a one-to-one-basis in suspended stainless steel cages with wire mesh floors. Mated females and males were individually housed in labelled polycarbonate cages containing sawdust (SAWI bedding, Jelu Werk, Rosenberg, Germany) as bedding material. Certificates of analysis were examined and then retained in the NOTOX archives. Offspring was kept with the dam until termination. In order to reduce environmental influences as much as possible, cages were arranged in a latin square design over the cage rack during the study period. Each cage was identified with a colour-coded label according to dose group, showing the study number, animal identifications and other experimental details. From arrival until mating, males and females were housed in separate rooms. During the final stage of the pregnancy period (from approximately day 16 of gestation onwards) and during lactation, paper (Enviro-dri, BMI, Helmond, The Netherlands) was supplied to each dam for incorporation in the nest. The paper was analysed for contaminants. This was replaced when soiled.
Diet Free access was allowed to standard pelleted laboratory animal diet (from Altromin (code VRF 1), Lage, Germany). Each batch was analysed for nutrients and contaminants were analysed on a regular basis. Results were examined and then retained in the NOTOX archives. Fresh diet was provided on a weekly basis, or at periodic intervals during pregnancy.
Water Free access was allowed to tap water. Certificates of analysis (performed quarterly) were examined and then retained in the NOTOX archives. Analysis of bedding, diet, paper and water did not reveal any findings that were considered to have affected study integrity.