| 6 weeks study |
Subchronic (30-90 days) |
The experiment started with 48 rats, distributed randomly, based on body weight, to 4 groups of 12 animals each. After one week of acclimatization, one group was treated with sodium (meta)arsenite (NaAsO2) 10 mg/kg b.w.: group As, another with sodium fluoride (NaF) 5 mg/kg b.w.: group F, and yet another with the combination of the two agents: group As+F (doses as above) by gavage (that is, via a fine glass tube inserted through the esophagus into the stomach), once a day, 5 days a week, for 6 weeks. The control group (Control) received distilled water (the solvent for NaAsO2 and NaF). (According to the municipal waterworks, local piped drinking water in Szeged contains merely 7 ?g/L As and 70 ?g/L F. Compared to the treatment doses given below, the amounts of arsenic and fluoride to which the rats were exposed from the drinking water were negligible.); Young adult Wistar rats – 7 weeks old, body weight: 160 ± 20 g, quality: specific pathogen free – were obtained from Toxi-Coop (Budapest, Hungary). The animals were kept in polypropylene home cages (3 rats/cage) under controlled conditions (12–12 h light/ dark cycle with light on at 06:00; temperature 22–24 °C, and 30–60 % relative humidity). The rats had free access to drinking water and standard rodent chow. |