Nitrophenols carcinogenicity

No studies were located regarding the carcinogenic effects in humans or animals following inhalation exposure to 2-nitrophenol or 4-nitrophenol. 

Application of 2-nitrophenol or 4-nitrophenol (dissolved in dioxane) to the shaved backs of mice in doses of 47 mg nitrophenol/kg/day for 12 weeks did not induce skin tumors or lesions that could be considered precancerous in nature (Boutwell and Bosch 1959). These results should be interpreted with caution, since no other site was examined and the duration of the study may have been too short for evaluating carcinogenic potential. 

Cancer. No studies were located regarding the carcinogenic potential of 2-nitrophenol or 4-nitrophenol in humans by any route of exposure or in animals by the inhalation or oral route. Neither isomer induced tumors when applied to the backs of mice in doses of 47 mg/kg/day for 12 weeks (Boutwell and Bosch 1959). However, since no other site was examined and the duration of the study was only 12 weeks, the results should be interpreted with caution. The relevance of this information to human health is unknown. NTP (1991) recently conducted a review of a 2-year skin painting study with 4-nitrophenol in mice. The panel concluded that under the conditions of the study, there was no evidence of carcinogenic activity in male or female Swiss-Webster mice receiving doses of up to 160 mg 4-nitrophenol/kg for 78 weeks. 

The NIEHS has sponsored a carcinogenicity study with 4-nitrophenol to be conducted FY 1990 by Litton Bionetics, Inc. (NTP 1990). In addition, NIEHS sponsored a mutagenesis/genetic toxicity study with 4-nitrophenol to be completed FY 1990 the performing organization was not specified (NTP 1990). An acute/chronic toxicity study on 4-nitrophenol sponsored by the FDA was to be completed FY 1990 (NTP 1990). 4-Nitrophenol has been selected for a... 

Nitrate and nitrite photochemistry might also play a role in atmospheric hydrometeors. Nitrite photolysis has been shown to account for the majority of hydroxyl photoformation in irradiated fog water from a polluted site [ 14]. In addition, the generation of mutagenic and carcinogenic compounds from amino acids and amines dissolved in fog water [147] is a process that can be linked with nitrite photochemistry [20,141]. Furthermore, the formation of atmospheric nitrophenols partially takes place in aqueous solution. Reactions in the aqueous phase can account for about 30% of the atmospheric sources of mononitrophenols and for the vast majority of the dinitrophenol ones [ 148], and irradiation of nitrate and nitrite can possibly play a role in the process (see Sect. 3.2). Mono- and dinitrophenols are toxic compounds, and their occurrence in rainwater is thought to be a contributory factor in forest decline [149-151]. 

ACGIH TLV TWA 1 ppm (skin) Animal Carcinogen BEI 5 mg/g creatinine of total p-nitrophenol in urine at end of shift at end of workweek... 

IARC. 1993a. International Agency for Research on Cancer. IARC monographs on the evaluation of the carcinogenicity risk of chemicals to humans 2-amino-4-nitrophenol 57 167-176. 

NCI. 1978. Bioassay of 4-amino-2-nitrophenol for possible carcinogenicity. National Cancer Institute, Technical Report Series No. 94. Carcinogenesis Testing Program, National Cancer... 

A number of common azo based dyes are known to be possible carcinogens. This results from their metabolism to more labile products in the liver. Analysis of these metabolites is obviously an important in a number of areas. Radzik et al. have utilised LC-DED in both in the redox mode and in parallel for the determination the metabolites of Disperse Orange 3 (viii) liver microsomal fractions. No prior extraction, preconcentration or derivatisation was required for the analysis of the principle metabolites 4-nitroaniline (ix), 2-amino-5-nitrophenol (x) and N-hydroxy-4-nitroaniline (xi) in the sub-pM range. 

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