Effect of Dietary Fat on Selected Parameters of Toxicity Following 1- or 3-Month Exposure of Rats to Toluidine Isomers

Abstract

The aim of the study was to investigate the effect of the dietary fat on selected parameters of toluidines toxicity in rats during subchronic exposure. Three isomers of toluidine (ortho, meta, and para) were administered to rats in the diet for 1 and 3 months at levels 40, 80, 160 mg/kg/day in two kinds of diet containing either 4% or 14% fat. All doses of toluidine isomers produced a 1.5- to 9.8-fold increase in methemoglobin (MetHb) level during both treatment periods. A distinct dose-response relationship was observed, especially for o- and m-toluidine; the effect was generally greater in rats fed high-fat diet. Reduced glutathione level in liver was increased in all treated groups, 1.5- to 5.1-fold, irrespective of the kind of diet. An increase in hepatic lipid peroxidation (thiobarbituric acid reactive substances; TBARS), 1.5- to 4.5-fold, was noticed in the majority of the treated groups. Generally, there was no consistent effect of diet except for p-toluidine where the level of hepatic TBARS was lower in rats fed high-fat diet. Blood urea nitrogen (BUN) level in animals treated with all doses of o- and m-toluidine was 1.3- to 5.0-fold higher in comparison with respective controls. No clear relationship between BUN level and the kind of diet was found. No effect of toluidines on the activity of serum aspartate aminotransferase (AST) and sorbitol dehydrogenase (SDH) were observed. In the majority of groups treated for 30 and 90 days the amount of toluidines in 24-h urine was lower in rats fed high-fat diet. Final body weight gain in rats treated with o- and p-toluidine (80 and 160 mg/kg body weight [b.w.]) was lower as compared to controls. In summary the high-fat diet stimulated methemoglobin formation in rats treated with o- and m-toluidine and cause the decrease in the amount of toluidines in 24-h urine. The high content of fat did not affect consistently the other parameters tested.

Removal of Aromatic Amino-derivatives from Aqueous Solutions Using Polymeric Supports Functionalized with Aminophosphonated/aminoacid-phosphonated Groups

“…It is an organic compound with three isomers (o-toluidine, m-toluidine and ptoluidine) [4]. O-toluidine has attracted great interest due to its carcinogenicity, while in meta and para isomers this effect is not significant [5]. The oral LD50 values in the rat are as follows: 670 mg/kg for otoluidine, 450 mg/kg for m-toluidine and 656 mg/kg for p-toluidine [5].…”

“…The environmental problems increased because of increasing population, consumption of natural habitat, and development of industrialization. However, the presence of aromatic amines in water, even at very low concentrations, is extremely harmful to aquatic life and human health [4,5]. The pharmaceutical manufacturing industry produces a wide range of products to be used as human and animal medications [6].…”