National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/8929

Target Organs and Levels of Evidence for TR-366

Toxicology and Carcinogenesis Studies of Hydroquinone (CASRN 123-31-9) in F344/N Rats and B6C3F1 Mice (Gavage Studies)

Chemical (Study Title)
CASRN
Peer Review DatePrimary UsesRoute/Exposure LevelsStudy Laboratory
Hydroquinone
123-31-9
10/03/1988Photographic developer. In manufacture of dyes, rubber antioxidants. Polymerization inhibitor, stabilizer. In skin-lightening creams; hair dyes. Found in coal tar effluent. An antioxidant in the rubber industry & as a developing agent in photography. Also an intermediate in the manufacture of rubber & food antioxidants & monomer inhibitors. Used as depigmenting agents to lighten skin. Associated with tobacco: reported either as a natural component of tobacco, pyrolysis product (in tobacco smoke), or additive for one or more types of tobacco products.Gavage
R: 0,25,50, M: 0,50,100 MG/KG/65 PER GROUP
American Biogenics Corp (Bioassay Systems)

Levels of Evidence

Male Rats: Some Evidence
TypeOrgan/Tissue (Lesion)
Neoplastic Lesions
  • Kidney Tubular Cell: Adenoma 0/55 4/55 8/55
Female Rats: Some Evidence
TypeOrgan/Tissue (Lesion)
Neoplastic Lesions
  • Hematopoietic System: Leukemia 9/55 15/55 22/55
Male Mice: No Evidence
TypeOrgan/Tissue (Lesion)
Non-Neoplastic Lesions
  • Thyroid Gland: Follicular cell, hyperplasia
  • Liver: Anisokaryosis; basophilic focus; syncytial alteration
Female Mice: Some Evidence
TypeOrgan/Tissue (Lesion)
Neoplastic Lesions
  • Liver: Adenoma 2/55 15/55 12/55; adenoma or carcinoma (combined) 3/55 16/55 13/55
Non-Neoplastic Lesions
  • Thyroid Gland: Follicular cell, hyperplasia


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