Evaluation of immunologic and intestinal effects in rats administered an E 171-containing diet, a food grade titanium dioxide (TiO2)

• Published in: Food and chemical toxicology Vol. 133; p. 110793
• Main Authors: Blevins, Lance K., Crawford, Robert B., Bach, Anthony, Rizzo, Michael D., Zhou, Jiajun, Henriquez, Joseph E., Khan, D. M. Isha Olive, Sermet, Sera, Arnold, Lora L., Pennington, Karen L., Souza, Nathalia P., Cohen, Samuel M., Kaminski, Norbert E.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.11.2019
• Subjects: 1,2-Dimethylhydrazine - pharmacology; Animals; Carcinogenesis - drug effects; Carcinogens - pharmacology; CD4-Positive T-Lymphocytes - drug effects; colon; Cytokines - metabolism; Dendritic Cells - drug effects; diet; Dietary titanium dioxide; E 171; feed intake; Food Additives - chemistry; Food Additives - toxicity; Gastrointestinal inflammation; histopathology; inflammation; interleukin-12; interleukin-17; Intestinal carcinogenesis; Intestinal Mucosa - drug effects; jejunum; liver; lungs; Male; Particle Size; Peyer's patches; Peyer's Patches - drug effects; rats; Rats, Wistar; spleen; T-Lymphocytes, Regulatory - drug effects; testes; Titanium - chemistry; Titanium - toxicity; titanium dioxide; toxicity; Tregulatory cells; Dietary titanium dioxide; Intestinal carcinogenesis; Gastrointestinal inflammation; E 171; Tregulatory cells; T(regulatory) cells
• ISSN: 0278-6915; 1873-6351; 1873-6351
• DOI: 10.1016/j.fct.2019.110793

The toxicity of dietary E 171, a food grade titanium dioxide was evaluated. A recent study reported rats receiving E 171 in water developed inflammation and aberrant crypt foci (ACF) in the gastrointestinal tract. Here, rats received food containing E 171 (7 or 100 days). The 100-day study included feeding E 171 after dimethylhydrazine (DMH) or vehicle only pretreatment. Food consumption was similar between treatment groups with maximum total cumulative E 171 exposure being 2617 mg/kg in 7 days and 29,400 mg/kg in 100 days. No differences were observed due to E 171 in the percentage of dendritic, CD4+ T or Treg cells within Peyer's patches or the periphery, or in cytokine production in plasma, sections of jejunum, and colon in 7- or 100-day E 171 alone fed rats. Differences were observed for IL-17A in colon (400 ppm E 171 + DMH) and IL-12p70 in plasma (40 ppm E 171 + DMH). E 171 had no effect on histopathologic evaluations of small and large intestines, liver, spleen, lungs, or testes, and no effects on ACF, goblet cell numbers, or colonic gland length. Dietary E 171 administration (7- or 100-day), even at high doses, produced no effect on the immune parameters or tissue morphology. •Dietary E 171 did not change immune cell profile in Peyer's patches or peripherally.•Dietary E 171 did not alter inflammatory cytokine profile in GI tract or circulation.•Dietary E 171 did not increase colonic proliferative lesions.•Dietary E 171 did not induce histopathologic changes in small and large intestine, liver, spleen, lungs, or testes.