Abstract

The in vivo effects of oral administration of varying concentrations (30, 60 and 120 mg/kg body wt) of sodium benzoate (a commonly used food preservative) on haemoglobin (Hb) concentration, white blood cell (WBC) count, total plasma protein and some plasma electrolytes (Na⁺, K⁺, Cl^-, and HCO₃^-) levels of wistar albino rats were investigated. The oral intake was done at 48-hourly intervals for 14 days. The rats were fed normal diet ad libitumand blood samples for the determinations were obtained at zero, 2-, 6-, and 14-days following intake. The results obtained for Hb (g/l) showed significant (p<0.05) decreases in a dose-dependent manner for the three concentrations of sodium benzoate. For WBC, significant (p<0.05) decreases were noted for 60 and 120 mg/kg body weight but no significant change occurred with 30 mg/kg body weight of sodium benzoate. The preservative did not significantly affect the total plasma protein concentrations. Significant increases (p<0.05) were obtained at the two concentrations of sodium benzoate from the 6^th day for Na⁺, K⁺ while HCO₃^- showed no significant change. No significant change was noted for Cl^- at the various concentrations of the preservative. These findings suggest possible changes in blood chemistry due to the preservative.

Key words: Sodium benzoate, haemoglobin, white blood cell, plasma proteins, electrolytes.