https://ntp.niehs.nih.gov/go/6251

Target Organs and Levels of Evidence for TR-470

Toxicology and Carcinogenesis Studies of Pyridine (CASRN 110-86-1) in F344/N Rats, Wistar Rats, and B6C3F1 Mice (Drinking Water Studies)

Chemical (Study Title)
CASRN		 Peer Review Date Route/Exposure Levels Study Laboratory
Pyridine
110-86-1		 12/10/1997 Dosed-Water
R: 0, 100, 200, OR 400 PPM MM: 0, 250, 500, OR 1000 PPM FM: 125, 250, OR 500 PPM MWR: 0, 100, 200, OR 400 PPM (50/SEX/GROUP)		 T.S.I. Mason Laboratories, Inc.

Levels of Evidence

Male Rats: Some Evidence
Type Organ/Tissue (Lesion)
Neoplastic Lesions
  • Kidney Tubular Cell: (SINGLE SECTIONS) ADENOMA 1/50 0/48 2/50 6/49 COMBINED 1/50 1/48 2/50 6/49 (SINGLE AND STEP SECTIONS) ADENOMA 2/50 3/48 6/50 10/49 COMBINED 2/50 4/48 6/50 10/49
Non-Neoplastic Lesions
  • LIVER: CENTRILOBULAR CYTOMEGALY; CYTOPLASMIC VACUOLIZATION; PERIPORTAL FIBROSIS; FIBROSIS; CENTRILOBULAR DEGENERATION OR NECROSIS; PIGMENTATION
Female Rats: Equivocal Evidence
Type Organ/Tissue (Lesion)
May Have Been Related
  • Hematopoietic System: MONONUCLEAR CELL LEUKEMIA 12/50 16/50 22/50 23/50
Non-Neoplastic Lesions
  • LIVER: CENTRILOBULAR CYTOMEGALY; CYTOPLASMIC VACUOLIZATION; CENTRILOBULAR DEGENERATION; BILE DUCT HYPERPLASIA; PIGMENTATION
Male Mice: Clear Evidence
Type Organ/Tissue (Lesion)
Neoplastic Lesions
  • Liver: ADENOMA 29/50 40/50 34/49 39/50 CARCINOMA 15/50 35/50 41/49 40/50 HEPATOBLASTOMA 2/50 18/50 22/49 15/50 COMBINED 38/50, 47/50, 46/49, 47/50
Female Mice: Clear Evidence
Type Organ/Tissue (Lesion)
Neoplastic Lesions
  • Liver: ADENOMA 37/49 39/50 43/50 34/50 CARCINOMA 13/49 23/50 33/50 41/50 HEPATOBLASTOMA 1/49 2/50 9/50 16/50 COMBINED 41/49, 42/50, 45/50, 44/50
 
Chemical (Study Title)
CASRN		 Peer Review Date Route/Exposure Levels Study Laboratory
Pyridine
110-86-1		 12/10/1997 Dosed-Water T.S.I. Mason Laboratories, Inc.

Levels of Evidence

Male Rats: Equivocal Evidence
Type Organ/Tissue (Lesion)
Neoplastic Lesions
  • Testis: INTERSTITIAL CELL ADEMONA 5/50 6/49 4/49 12/50
Non-Neoplastic Lesions
  • LIVER: CENTRILOBULAR DEGENERATION AND NECROSIS; FIBROSIS; PERIPORTAL FIBROSIS; PIGMENTATION
    • GLANDULAR STOMACH: MINERALIZATION
    • PARATHYROID GLAND: HYPERPLASIA