title: Acute and sub-chronic oral toxicity study of black tea in rodents.
abstract: OBJECTIVE
  Systematic oral toxicity study for black tea (Camellia sinensis), the most commonly consumed variety of tea, is lacking. The present study was undertaken to assess the iron load on black tea (Camellia sinensis) and its safety aspects in animals.
  
  
  METHODS
  The analysis of iron was done in six tea samples as per American Public Health Association method using flame atomic absorption spectrophotometer. Maximum physical iron-loaded tea sample was identified on black tea sample 2 (BTS-2), and this was further studied for acute and 90-day sub-chronic toxicity following Organisation for Economic Co-operation and Development guidelines.
  
  
  RESULTS
  Black tea sample 2 did not show any signs of toxicity or mortality at up to 2 g/kg per oral dose in Swiss albino mice. 90-day toxicity studies in Wistar rats did not reveal any evidence of toxicity at up to 250 mg/kg/day (2.5% infusion of BTS-2) oral dose as exhibited by regular observations, body weight, food consumption, hematology, serum chemistry, organ weights, and histopathology. Further, serum iron, total iron binding capacity, unsaturated iron binding capacity, and ferritin were not altered after 90 days of treatment. Masson trichrome staining and Perls' staining did not reveal any abnormalities in hepatic tissue following 90-day treatment of high iron-loaded BTS-2.
  
  
  CONCLUSIONS
  This safety study provides evidence that BTSs, in spite of relatively high iron content, show no significant iron-related toxicity on acute or sub-chronic oral administration in animals.
authors: Department of Pharmacology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors: Tapas Kumar
authors: TK
authors: Sur
authors: Department of Pharmacology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors: Suparna
authors: S
authors: Chatterjee
authors: Scientist, Chemistry Division, Quality Testing Laboratory (AYUSH), Ramakrishna Mission Ashrama, Vivekananda University, Narendrapur, West Bengal, India.
authors: Alok Kumar
authors: AK
authors: Hazra
authors: Department of Pharmacology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors: Richeek
authors: R
authors: Pradhan
authors: Department of Pharmacology, College of Medicine and Sagore Dutta Hospital, Kolkata, West Bengal, India.
authors: Supriyo
authors: S
authors: Chowdhury
mesh_terms: D000818:Animals; D001772:Blood Cell Count; D001774:Blood Chemical Analysis; D001835:Body Weight / Q000187:drug effects; D028241:Camellia sinensis / Q000737:chemistry / Q000633:toxicity*; D005260:Female; D005506:Food Contamination / Q000032:analysis*; D007501:Iron / Q000097:blood / Q000302:isolation & purification / Q000633:toxicity; D008099:Liver / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D009929:Organ Size / Q000187:drug effects; D017208:Rats, Wistar; D013662:Tea / Q000737:chemistry / Q000633:toxicity*; D023382:Toxicity Tests, Acute; D059550:Toxicity Tests, Subchronic
chemical_list: D013662:Tea; D007501:Iron
keywords: Atomic absorption spectrophotometer; black tea; iron; oral toxicity; rodent