3,3'-dichlorobenzidine dihydrochloride

Epidemiological data

Administrative data

Endpoint:

epidemiological data

Type of information:

other: cancer incidence data collection

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented study report which meets basic scientific principles.

Data source

Reference

Reference Type:

other company data

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Study type:

cohort study (retrospective)

Endpoint addressed:

carcinogenicity

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

EPIDEMIOLOGICAL STUDY

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

3,3'-dichlorobenzidine dihydrochloride

EC Number:

210-323-0

EC Name:

3,3'-dichlorobenzidine dihydrochloride

Cas Number:

612-83-9

Molecular formula:

C12H10Cl2N2.2ClH

IUPAC Name:

3,3'-dichloro-[1,1'-biphenyl]-4,4'-diamine dihydrochloride

Method

Type of population:

occupational

Ethical approval:

not specified

Details on study design:

99 persons (88 men and 11 women) who had worked with DCBDC for at least one year since 1947 were included into these examinations. From 1947 to 1993, clinical examinations were made once a year, with cytological examinations of the urine every six months on all persons exposed to DCB in the plant area and in the laboratories. The occurence of cancer in this group was compared with the figures expected for the normal population.

Details on exposure:

Over the years, a number of DCBDC measurements have been taken in relation to the working environment. From 1983 the Analytical Laboratory has taken measurements on airborne dust to analyze for DCBDC. Dust was collected on a filter (0.8 µm), which is then weighed. As not all dust is DCBDC, the filter is washed out and a chemical analysis made on DCBDC in the liquid.

Results and discussion

Results:

Among the 99 persons, 88 were men and 11 women. In the period from 1947 to 1990, there was a total of 6 cases of cancer among the men (5.19 were expected). Among the women there were no cases of cancer (0.23 expected).

Applicant's summary and conclusion

Conclusions:

On the basis of work published previously and this epidemiological study, it is concluded that DCBDC itself does not promote cancer in human beings under common working conditions.

Executive summary:

Since DCBDC was introduced in the plant in Koge, there have been medical examinations of employees as well as urine cytology testing at least once a year. Furthermore, we have investigated through the Danish Cancer Society the incidence of cases of cancer among all employees at Sun Chemical A/S (KVK) exposed to DCBDC up to 1990. These investigations show that there seems to be no risk of cancer when working with DCBDC during pigment production. On the present showing, DCBDC in itself does not seem to have a carcinogenic effect on human beings.