Safety evaluation of certain food additives - ipcs inchem

130 PHYTOSTEROLS, PHYTOSTANOLS AND THEIR ESTERS
dependency and reached statistical significance only for the 1.25% female dose
group at the end of treatment. Serum vitamin A and E levels were unaffected by
treatment, and concentrations of vitamins D and K and -carotene in serum were
below the respective limits of detection. Inflammation of the caecum, colon and
rectum was slightly more frequent and severe in treated males compared with
controls. However, this observation showed no dose dependency and was absent
in female rats (an opposite trend was observed in high-dose females, where
inflammation of the large intestine was less than in controls). The NOEL in this study
is 5% MPSS-SE in the diet, which, according to the authors, equals 4.2 g/kg bw per
day for males and 4.8 g/kg bw per day for females (Wedig, 2000).
After the change in the manufacturing process, MPSS-VD was investigated
in a 90-day dietary study in rats conducted according to OECD Test Guideline
408 and in compliance with OECD GLP principles. Concentrations of 0, 1.25, 2.5
or 5% MPSS-VD in the diet, equal to 0, 0.99, 2.0 and 4.1 g test material/kg bw
per day for males and 0, 1.1, 2.2 and 4.6 g test material/kg bw per day for females
(mean intakes over the study period), were administered to 20 Sprague-Dawley rats
per group and sex for at least 90 days. Investigations included measurement of body
weights and food consumption and clinical and neurobehavioural observations
during the study, ophthalmological examination before and after treatment,
urinalysis, and measurement of haematological and clinical chemistry parameters.
Organ weights were determined, and organs (tissues of control and high-dose
animals) were examined histopathologically. Furthermore, animals were subjected
to a battery of functional and motor activity tests before and after treatment. Plasma
vitamin levels were not determined in this study. No consistent treatment-related
changes in any of these parameters were observed, apart from the transient
occurrence of red mucous membranes in 3, 6, 7 and 12 of 20 male rats and 1, 10,
6 and 17 of 20 female rats at dose levels of 0, 1.25, 2.5 and 5% MPSS-VD,
respectively. Also, some statistically significant differences in clinical chemistry
parameters between treated and untreated animals were observed in female, but
not in male, animals. In female rats, serum alanine aminotransferase and -glutamyl
transferase activities were increased at 2.5% and 5% MPSS-VD (without clear dose
dependency), urea concentration was increased at the highest dose and albumin
was decreased in the low- and mid-dose groups. Whereas these observations may
be an early indication of effects in the liver, no changes were observed in the liver
in the histopathological investigations. The NOEL in this study is 5% MPSS-VD in
the diet, which, according to the authors, equals 4.1 g/kg bw per day for males and
4.6 g/kg bw per day for females (Robbins, 2002).
2.3.2 Genotoxicity
Mixtures of phytostanols and phytosterols derived from both solvent
extraction (MPSS-SE) and vacuum distillation (MPSS-VD) were examined in a
series of in vitro and in vivo genotoxicity studies. All studies were conducted in
compliance with OECD principles of GLP. Studies on MPSS-VD by Krul & van
Ommen (2001) and de Vogel (2001) were carried out according to OECD Test
Guidelines 471 and 473, respectively. No genotoxic activity of any of the mixtures
was observed in these studies, which are summarized in Table 2.