Safety evaluation of certain food additives - ipcs inchem

STEVIOL GLYCOSIDES (addendum) 191
No deaths or physical signs of toxicity were observed in any of the groups.
Slight differences in mean body weight gains and food consumption on day 1 but
not thereafter were observed between animals in the 50 000 mg/kg diet groups and
above and control groups. Females receiving diets containing 50 000 mg
rebaudioside A/kg showed a statistically significant decrease in mean total white
blood cell and lymphocyte count, although individual values were within the historical
control range. There was a statistically significant increase in mean creatinine
values in males and females given diets containing 75 000 mg/kg or above and in
males receiving 25 000 or 50 000 mg/kg. Sodium and chloride levels in females
receiving the 100 000 mg/kg test diet were statistically significantly higher than
those in controls. Sodium levels were outside the range of historical controls, but
chloride levels were not. Mean levels of bile acids were significantly lower than in
controls in males and females receiving 75 000 mg/kg or above and in females
receiving 25 000 or 50 000 mg/kg, although these were attributed to one male and
two female animals in the control group with abnormally high values. A significant
increase in specific gravity of the urine was observed in males receiving 75 000 or
100 000 mg/kg, and urinary protein was significantly higher than in controls in males
receiving 50 000 mg/kg or above, although this was still within historical control
values. Adjusted mean weights of the hearts of males receiving 75 000 mg/kg or
above and the adrenals of females receiving 50 000 mg/kg or above were
marginally, but statistically significantly, lower than in controls. Absolute testis
weights were marginally, but statistically significantly, lower in males receiving
100 000 mg/kg when compared with controls. No other treatment-related effects
were observed (Stamp, 2006a; Curry & Roberts, 2008). The NOEL in this study was
100 000 mg rebaudioside A/kg in the feed or 4286 mg/kg bw per day expressed
as steviol.
Three groups of 20 female and 20 male HsdRcc Han Wistar rats received
a diet containing 0, 12 500, 25 000 or 50 000 mg rebaudioside A (97% purity)/kg
for 13 weeks (mean doses equal to 0, 970, 2003 and 4161 mg/kg bw per day in
males and 0, 1141, 2328 and 4645 mg/kg bw per day in females, or 0, 319, 660 and
1370 mg steviol/kg bw per day in males and 0, 376, 767 and 1530 mg steviol/kg bw
per day in females). This study was carried out in compliance with GLP and OECD
guidelines. Free access to control or test diets and drinking-water was permitted
throughout the study except overnight prior to blood and urine tests. Before and
during the treatment period, sensory reactivity and motor activity were tested and
an ophthalmic examination was carried out. Blood and urine samples were taken
on days 10, 46 and 89 of the study. Blood and urine samples were analysed for a
complete range of clinical chemistry parameters, and blood was analysed for a
complete range of haematological parameters. Bone marrow samples were
obtained at necropsy. Animals were sacrificed at the end of the treatment period,
and several organs were weighed. Examination with a light microscope or histological
testing was carried out on a range of organs in the control and highest dose
groups. Two animals were killed for welfare reasons during the treatment period as
a result of damage incurred during the blood collection process.
Forelimb grip strength was low for males in the high-dose group in weeks 4,
8 and 12, and hindlimb grip strength in males for all treatment groups was low in