2-amino-4-chlorophenol

Carcinogenicity

Administrative data

Endpoint:

carcinogenicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Data source

Reference

Reference Type:

publication

Title:

Oral carcinogenicity and toxicity of 2-amino-4-chlorophenol in rats

Author:

Yamazaki K, Suzuki M, Kano H, Umeda Y, Matsumoto M, Asakura M, Nagano K, Arito H, Fukushima S.

Year:

2009

Bibliographic source:

Journal of Occupational Health

Materials and methods

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

2-amino-4-chlorophenol

EC Number:

202-458-9

EC Name:

2-amino-4-chlorophenol

Cas Number:

95-85-2

Molecular formula:

C6H6ClNO

IUPAC Name:

2-amino-4-chlorophenol

Test material form:

not specified

Test animals

Species:

rat

Sex:

male/female

Administration / exposure

Route of administration:

oral: feed

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

13 weeks/ 2 years

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

512 ppm

Remarks:

(w/w) for 13 wk

Doses / concentrations 2

Dose / conc.:

1.28 ppm

Remarks:

(w/w) for 13 wk

Doses / concentrations 3

Dose / conc.:

3.2 ppm

Remarks:

(w/w) for 13 wk

Doses / concentrations 4

Dose / conc.:

8 ppm

Remarks:

(w/w) for 13 wk

Doses / concentrations 5

Dose / conc.:

20 ppm

Remarks:

(w/w) for 13 wk

Doses / concentrations 6

Dose / conc.:

1.28 ppm

Remarks:

(w/w) for 2 yr

Doses / concentrations 7

Dose / conc.:

3.2 ppm

Remarks:

(w/w) for 2 yr

Doses / concentrations 8

Dose / conc.:

8 ppm

Remarks:

(w/w) for 2 yr

No. of animals per sex per dose:

10 rats of both sexes - dose level of 0 (control), 512, 1,280, 3,200, 8,000 or 20,000 ppm (w/w) - for 13 wk
50 rats of both sexes - dose level of 0 (control), 1,280, 3,200 or 8,000 ppm (w/w) - for 2 yr

Control animals:

yes

Results and discussion

Results of examinations

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Food efficiency:

effects observed, treatment-related

Description (incidence and severity):

The 13-wk oral subchronic toxicity of ACP (2-amino-4-chlorophenol) was characterized by proliferative lesions leading to development of tumors in the forestomach and urinary bladder and by erythrocyte toxicity as evidenced by decreases in red blood cell counts, hemoglobin and hematocrit and concurrent increases in methemoglobin levels and reticulocyte counts. Both simple and papillary and/or nodular types of transitional cell hyperplasias were observed in the urinary bladder of ACP-fed male rats. The proliferative lesions appeared at higher doses of ACP after the 13-wk administration than clear erythrocyte toxicity did.

The 2-yr oral administration of ACP significantly increased incidences of squamous cell papillomas and carcinomas in the forestomach of male and female rats and transitional cell carcinomas in the urinary bladder of male rats. These tumor incidences increased dose-dependently. Notably, clear signs of erythrocyte toxicity were not evident after the 2-yr administration of ACP.

Applicant's summary and conclusion

Conclusions:

Clear evidence of carcinogenic activity of ACP (2-amino-4-chlorophenol) was shown in male and female rats. These data might be useful for the health risk assessment of workers exposed to ACP

Executive summary:

The substance is classified as suspected of causing cancer. (CLP Regulation - category 2)