Some Toxicity Studies On Sulphite Interaction Products in Food.

3-Deoxy-4-sulphohexosulose (DSH), a compound that may be formed in significant amounts in dehydrated foods during the SO2-inhibited Maillard reaction was synthesised and its toxicology studied. The intra-gastric acute toxicity of DSH was investigated in male and female wistar albino rats and CF1 mice. The exceeded 5 g DSH/ Kg body weight in each case. At this dose level no adverse effects other than an initial, transient diarrhoea was seen during a fourteen-day observation period after dosing. Urinalysis, haematology and post-mortem examinations in both species did not reveal any pathological changes. A short-term study (21 days) was performed on male wistar albino rats at dietary levels of DSH of 0, 0.5 and 2%. No adverse effects were observed on food intake, growth rate, haematology nor serum biochemistry but urinalysis revealed a slight diuretic effect of DSH on the rats of the 2% DSH dose group. Histology of selected organs did not show any dose-related pathological changes. A short-term study (90 days) was performed on male CF1 mice at dietary levels of DSH of 0, 0.5, 1 and 2%. No adverse effects were observed on food intake, growth rate, urinalysis, haematology nor serum biochemistry but two animals of the 2% DSH dose group developed large urinary bladder calculi composed mainly of calcium oxalate. Similar histopathological changes were evident in the urinary system of both-test and control animals. DSH was non-mutagenic to the strains of Salmonella typhimurium TA 98, TA 100, TA 1535 and TA 1537 in the Ames test. 14C - DSH and 35S - DSH were also synthesised and their metabolism studied in male wistar albino rats and CF1 mice. Both 14C- and 35S-labelled DSH showed similar patterns of excretion consistent with rapid, incomplete absorption from the upper gastrointestinal tract and rapid excretion of the absorbed DSH in the urine in both species. These observations were corroborated by plasma levels studies of 14C - DSH and 35S - DSH and tissue distribution studies of 14C - DSH in both species. 14C - DSH was not found to be covalently bound to plasma proteins and no evidence was found that DSH entered intermediary metabolism in either species. Chromatographic studies indicated that DSH was mainly excreted unchanged in the urine in both species. A short-term study (90 days) performed on male wistar albino rats fed stored sulphited model diets revealed growth retardation, transient alopecia and increased relative weights of certain gastrointestinal tract organs. The mechanisms by which these effects occurred are discussed