“It is reasonable to suspect that India Ink could produce an acute colitis…including direct toxic effect, indirect manipulation, and immune complex-mediated inflammatory response.”
Gopal D., Morava-Protzner I., Miller A.B.H., Hemphill D.J. Idiopathic inflammatory bowel disease associated with colonic tattooing with India Ink preparation – case report and review of literature. Gastrointest Endosc. 1999 May;49(5):636-9.