Assessment of the mutagenic potential of hexavalent chromium in the duodenum of big blue® rats.
Toxicol Appl Pharmacol
; 330: 48-52, 2017 09 01.
Article
em En
| MEDLINE
| ID: mdl-28687238
ABSTRACT
A cancer bioassay on hexavalent chromium Cr(VI) in drinking water reported increased incidences of duodenal tumors in B6C3F1 mice at exposures of 30-180ppm, and oral cavity tumors in F344 rats at 180ppm. A subsequent transgenic rodent (TGR) in vivo mutation assay in Big Blue® TgF344 rats found that exposure to 180ppm Cr(VI) in drinking water for 28days did not increase cII transgene mutant frequency (MF) in the oral cavity (Thompson et al., 2015). Herein, we extend our analysis to the duodenum of these same TgF344 rats. At study termination, duodenum chromium levels were below either the limit of detection or quantification in control rats, but were 24.6±3.8µg/g in Cr(VI)-treated rats. The MF in control (23.2×10-6) and Cr(VI)-treated rats (22.7×10-6) were nearly identical. In contrast, the MF in the duodenum of rats exposed to 1-ethyl-1-nitrosourea for six days (study days 1, 2, 3, 12, 19, 26) increased 24-fold to 557×10-6. These findings indicate that mutagenicity is unlikely an early initiating event in Cr(VI)-induced intestinal carcinogenesis.
Palavras-chave
Texto completo:
1
Temas:
ECOS
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Aspectos_gerais
Bases de dados:
MEDLINE
Assunto principal:
Poluentes Químicos da Água
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Cromo
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Duodeno
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Mutagênicos
Limite:
Animals
Idioma:
En
Revista:
Toxicol Appl Pharmacol
Ano de publicação:
2017
Tipo de documento:
Article