Subchronic oral toxicity study with regular and enzymatically depolymerized sodium carboxymethylcellulose in rats

Area of Science:

• Food Science
• Toxicology
• Biochemistry

Background:

• Sodium carboxymethylcellulose (CMC) is a well-established food additive.
• Enzymatically depolymerized CMC (CMC-ENZ) is a novel functional food ingredient with lower molecular weight and viscosity.
• Both compounds are poorly absorbed and generally recognized as safe.

Purpose of the Study:

• To evaluate the subchronic oral toxicity of CMC-ENZ.
• To compare the toxicological profile of CMC-ENZ with that of regular CMC.
• To assess the safety of CMC-ENZ as a functional food ingredient.

Main Methods:

• A 3-month oral toxicity study in Wistar rats (7 groups, 20 rats/sex/group).
• Dietary administration of 0%, 2.5%, 5%, and 10% CMC and CMC-ENZ.
• Monitoring of water intake, urine production, urinary electrolytes, plasma alkaline phosphatase, and histopathological examination.

Main Results:

• Increased water intake, urine production, and urinary sodium excretion were observed in dose-dependent manner for both CMC and CMC-ENZ.
• Diarrhea, caecal enlargement, slight increase in plasma alkaline phosphatase, and altered urinary calcium and citrate were noted.
• Nephrocalcinosis and urothelial hyperplasia occurred in some groups, linked to alkaline urine and increased calcium excretion.
• No significant differences in the frequency or severity of observed effects between CMC and CMC-ENZ groups.

Conclusions:

• CMC-ENZ and CMC exhibit similar toxicological profiles.
• The observed effects are considered generic for poorly digestible carbohydrates.
• CMC-ENZ demonstrates comparable safety to CMC as a functional food ingredient.