Title: Alternative Sweeteners

Acesulfame K 19
The acute oral toxicity of acesulfame K is so low that it can be regarded
as practically nontoxic. The LD 50 was orally determined at 6.9–8.0 g/kg body
weight. The intraperitoneal LD 50 is 2.2 g/kg body weight (22). Subchronic toxic
effects were investigated in a 90-day study with rats. The animals were fed concentrations
from 0–10% acesulfame K in the diet. Potential carcinogenicity and
chronic toxicity were studied in rats that were fed up to 3% acesulfame K in the
diet. A carcinogenicity study was conducted in mice fed with concentrations up
to 3% acesulfame K. In addition, chronic toxicity effects of acesulfame K were
studied in beagle dogs for 2 years (22).
No mutagenicity was found in various respective studies. Among such studies,
there were a dominant lethal test; a micronucleus test; bone marrow investigations
in hamsters; tests for malignant transformation, DNA binding, and others
(22).
In reproduction studies with rats fed acesulfame K, no deviation was seen
in fertility, the number of young animals per litter, body weight, growth, or mortality
(22).
The toxicological studies on acesulfame K demonstrated that the compound
would be safe for use as an intense sweetener. This view was confirmed by the
Joint Expert Committee on Food Additives of the FAO and WHO, according
to which the data showed that acesulfame K did not exhibit mutagenicity or
carcinogenicity. Therefore, an acceptable daily intake (ADI) of 0–9 mg/kg of
body weight was allocated, which was later increased to 0–15 mg/kg (23). The
Scientific Committee for Foods of the EU published an assessment stating that
long-term studies did not show any dose-related increase in specific tumors nor
any treatment-related pathological changes of significance. Therefore, an acceptable
daily intake of 0–9 mg/kg of body weight was allocated (24). On the basis
of a detailed evaluation of the available animal studies, the Food and Drug Administration
in the United States also allocated an acceptable daily intake of up
to 15 mg/kg of body weight (25).
C. Metabolism and Physiological Characteristics
Acesulfame K is not metabolized by the human body. To investigate possible
metabolic transformations, 14 C-labeled acesulfame K was used. Studies were carried
out in rats, dogs, and pigs. Because animal studies did not show any metabolism,
human volunteers were also given labeled acesulfame K. The different animal
species, as well as the human volunteers, excreted the original compound.
No activity attributable to metabolites was found.
Because acesulfame K is excreted completely unmetabolized, it does not
have any caloric value.
In conjunction with the metabolic studies, the pharmacokinetics of acesulfame
K were also investigated. These studies were carried out with rats, dogs,