N-1-naphthylaniline

Epidemiological data

Administrative data

Endpoint:

epidemiological data

Type of information:

other: epidemiological study

Adequacy of study:

disregarded due to major methodological deficiencies

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Data source

Reference

Reference Type:

publication

Title:

A cohort study on cancer among workers exposed to an antirust oil.

Author:

Järvholm, B. and Lavenius, B.

Year:

1981

Bibliographic source:

Scand J Work Environ Health 7: 179-184

Materials and methods

Study type:

cohort study (retrospective)

Endpoint addressed:

carcinogenicity

Principles of method if other than guideline:

A cohort study on cancer among workers exposed to an antirust oil containing N-phenyl-1-naphthylamine: an epidemiologic study in an engineeringcompany was prompted by the observation of three cases of cancers.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

N-1-naphthylaniline

EC Number:

201-983-0

EC Name:

N-1-naphthylaniline

Cas Number:

90-30-2

Molecular formula:

C16H13N

IUPAC Name:

N-phenylnaphthalen-1-amine

Details on test material:

- Name of test material (as cited in study report): N-phenyl-1-naphthylamine
- Analytical purity: no data

Method

Details on study design:

HYPOTHESIS TESTED: There has been concern about cancer hazards from various industrial chemicals, among them oils with various contaminantsand additives. Therefore, when it was reported that three cases of cancer had occured among the personnel in a rather small department, this study was initiated to delineate further the mortality pattern among the employees.

METHOD OF DATA COLLECTION
- Details: By means of the personnel register all those individuals were identified.

STUDY PERIOD: 1954-1957 (oocupational); individuals were traced in the parish records through 1976.

STUDY POPULATION
- Selection criteria: Individuals had worked at any time between 1954 and 1957 in the department where the three original cases of cancer were observed and where the sepcific oil had been used (group A)
- Sex and age: Group A was composed of 78 women and 20 men. The study comprised persons born between 1893 and 1942.
- Total number of subjects participating in study: 162
- Total number of subjects at end of study: 162

COMPARISON POPULATION
- Type: Control or reference group / Other comparison group: Groups B/C
- Details: Referents were obtained from another packing department where the specific oil not had been used (group B). The antirust oil had also beenused at some other workplaces within the company, and some individuals were sensitized briefly after its introduction in 1954. Those who became sensitized and had medical treatment for eczema were registered in 1955 and entered on a list. These individuals from various departments were tested by a dermatologist in 1954 and 1955 and according to a letter from 1955 "half of them were allergic to N-phenyl-1-naphthylamine". The individuals on this list constituted group C.
Group B contained 27 women and 8 men. Group C constituted 23 men and 8 women.

HEALTH EFFECTS STUDIED
- Disease(s): cancer incidence

OTHER DESCRIPTIVE INFORMATION ABOUT STUDY: The potential influence of random variation on the difference between observed and expected incidence was described through the calculation of p-values on the Poisson distribution; only two-tailed p-values below 0.05 are indicated.

Exposure assessment:

estimated

Results and discussion

Results:

FINDINGS
Twelve women but no men in group A were found in the Cancer Register. All cancers were diagnosed between 1964 and 1973, and the cancer morbidity for the women was considerably increased. Mortality was also increased for the women, but the entire increase was explained by an increased mortality from cancer. In groups B and C there was no increased cancer morbidity or increased mortality. Two of the workers in group C developed cancer of the bladder, one of whom (a woman) was also included in group A.

Confounding factors:

Smoking and lifestyle characteristic; other chemicals

Strengths and weaknesses:

It is not clear from what chemical and/or environmental conditions the cancer cases were caused. Exposure conditions and possibilities are hypothesized. Groups B and C were small, and the outcome of these groups must therefore be interpereted as "nonpositive" rather than negative.

Any other information on results incl. tables

Composition of the investigated anti-rust oil used by groups A and C:

Substance	Concentration
White spirit	50.0 %
Mineral oil (acid refined)	16.5 %
Lanolin	16.5 %
Zinc naphthenate	16.5 %
N-phenyl-1-naphthylamine	0.5 %^a

^a: Originally the content was 2.0 %, but the concentration was lowered after a few months because of skin problems.

Morbidity from cancer and mortality in the different groups allowing for a latency period of at least 5 years:

	Observed	Expected	Rate ratio	95 % confidence interval of the rate ratio^c
Group A Women
Morbidity from cancer	12**	3.9	3.1	1.6-5.4
Mortality from all causes	8	4.3	1.9	0.8-3.7
Mortality from cancer	6*	1.7	3.5	1.3-7.6
Men
Morbidity from cancer	0	0.7	0
Mortality from all causes	1	1.8	0.6
Mortality from cancer	0	0.4	0
Group B
Morbidity from cancer	4^a	2.0	2
Mortality from all causes	1	4.4	0.2
Group C
Morbidity from cancer	4^b	3.8	1.1
Mortality from all causes	9	10.0	0.9	0.4-1.7

^a: Cancer of the collum of the uterus, unclassified tumor of inguen, cancer of the pancreas, and cancer of the breast.

^b: Cancer of the stomach, cancer of the pleurae, and two cases of cancer of the bladder.

^c: Confidence interval due to a Poisson distribution. Only intervals with expected or observed values of more than 5 are indicated.

* p<0.05, ** p<0.005