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Administrative data

Endpoint:
health surveillance data
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1976-1977
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Meets generally accepted scientific standards with acceptable restrictions
Cross-referenceopen allclose all
Reason / purpose for cross-reference:
reference to same study
Reason / purpose for cross-reference:
reference to other study

Data source

Reference
Reference Type:
publication
Title:
Nickel concentrations in nasal mucosa, plasma, and urine in active and retired nickel workers.
Author:
Torjussen W, Andersen I
Year:
1979
Bibliographic source:
Ann Clin Lab Sci. Jul-Aug;9(4):289-98

Materials and methods

Study type:
biological exposure monitoring
Endpoint addressed:
basic toxicokinetics
Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
The authors measured total nickel concentrations in the mucosa, blood and urine of current and retired nickel workers and compared levels to those measured in control subjects.
GLP compliance:
not specified

Test material

Constituent 1
Reference substance name:
Matte, nickel
EC Number:
273-749-6
EC Name:
Matte, nickel
Cas Number:
69012-50-6
Molecular formula:
Not applicable
IUPAC Name:
Nickel matte
Details on test material:
- Name of test material (as cited in study report): total nickel was measured but it was stated that workers were exposed to nickel matte (converter matte, which consists of about 50% nickel, 30% copper, 20% sulphur, and some trace metals), nickel oxide, and nickel subsulphide

Method

Type of population:
occupational
Ethical approval:
not specified
Details on study design:
OBJECTIVE:
-procure quantitative data from active and retired nickel workers and from controls on the nickel content in nasal mucosa, plasma and urine, and to study how duration of exposure and variation in nickel concentrations and nickel compounds in the working atmosphere influenced the nickel content in the nasal mucosa, blood and urine


TYPE OF EXPOSURE:
-Nickel refining process: raw material is converter matte (about 50 percent nickel, 30 percent copper, 20 percent sulphur and some trace metals) which is refined through crushing, roasting, smelting and electrolysis
-roasting/smelting workers mainly exposed to dry dust containing nickel subsulphide and oxide, corresponding to an average atmospheric concentration of about 0.5 mg Ni per m3 (range 0.1 to 1.0 mg per m3)
-electrolytic workers are mainly exposed to aerosols of nickel sulphate and (chloride, with an average air concentration of about 0.2 mg Ni per m3 (range 0.1 to 0.5 mg per m3) -non-process workers are exposed to miscellaneous nickel composites corresponding to an average air concentration of 0.1 mg Ni per m3 (range 0.01 to 0.5 mg per m3)
- nickel concentrations were registered by the Department for Occupational Hygiene and Safety at the plant from atomic absorption analyses of air samples collected by stationary and portable apparatus

DESCRIPTION / DELINEATION OF EXPOSURE GROUPS / CATEGORIES: nickel exposed workers (current and retired), controls
-Workers from the Falconbridge Nikkelverk, Kristiansand, Norway
-Nickel-exposed group: subjects employed at least 8 years at the plant and working with crushing, roasting, smelting, or electrolysis on 01Oct76; 20% of remaining non-process workers employed at least 8 years were selected randomly. 370 people eligible; 318 consented to the study (316 men, 2 women)
-Retired nickel workers: 15 male pensioners with at least 8 years of previous employment as process workers were chosen by the medical officer
-Control group: 57 male volunteer patients from the County Hospital; subjects were selected to match the nickel exposed group by age

SAMPLE COLLECTION
- blood, urine and biopsy samples were collected in the morning before breakfast during the last 3 months of the year 1976 from active and retired nickel workers and during the last 3 months of 1977 from the controls
- blood: drawn into heparinized Vacutainer tubes; plasma analyzed within 2-3 hours (for the controls, stored at -35ºC until analyses)
- urine: collected into acid-washed urine glasses and decanted into Vacutainer tubes analyzed within 2-3 hours (for the controls, stored at -35ºC until analyses)
- biopsy: specimens were taken from the anterior curvature of the middle nasal turbinate with a biopsy forceps from the nasal cavity with the best air-flow passage or from the side showing pathological changes

SAMPLE ANALYSIS
-measurements of nickel concentrations in the plasma, urine, and nasal mucosa were made with an atomic absorption spectrophotometer

STATISTICAL METHODS
-student t-test applied to calculate significant differences between means and correlation coefficients
-correlation coefficients were calculated between nickel concentrations in nasal mucosa, plasma or urine and the number of years from the first employment at the nickel refinery and between worker categories

OTHER
-work history, occupational nickel exposure and smoking habits were evaluated from a questionnaire and an interview

Results and discussion

Results:
NICKEL CONCENTRATIONS
Nickel Exposed Group
- Mean: in plasma: 6.3 µg/L; in urine: 49.1 µg/L; in mucosa: 273.9 µg per 100g wet weight
- Highest: in plasma: 36 µg/L; in urine: 600 µg/L; in mucosa: 3,460 µg per 100g wet weight
- statistically significant correlation between plasma and urine nickel concentrations; non-significant correlation between nickel concentrations in plasma and nasal mucosa
-283 workers (89%) had nickel values for plasma or urine above normal limit
-271 workers (85.8%) had nickel levels in the mucosa that were higher than the normal limit

Retired nickel workers
- Mean: in plasma: 2.9 µg/L; in urine: 11.3 µg/L; in mucosa: 114.4 µg per 100g wet weight
- Highest: in plasma: 7.0 µg/L; in urine: 42 µg/L; in mucosa: 720 µg per 100g wet weight
- statistically significant correlation between plasma and urine nickel concentrations
-5 workers (33%) had raised nickel values in plasma or urine
-6 workers (40%) had nickel levels in the mucosa that were higher than the normal limit

RELATION OF NICKEL CONCENTRATIONS TO EXPOSURE
-mean values of nickel in biological samples from the control group are significantly lower than levels in active and retired workers; difference in means between active and retired worker levels in plasma also significant
-differences in mean nickel plasma and urine different between the three worker categories; highest levels found in electrolysis followed by roasting/smelting, then non-process work
-in nasal mucosa, highest mean nickel concentrations were found in subjects from the roasting/smelting department, followed by non-process and electrolytic workers
-significant correlations between roasting/smelting work and raised nickel in nasal mucosa and between electrolytic work and raised plasma or urine nickel were observed
-significant correlations between length of nickel exposure and nickel concentrations in mucosa, plasma and urine were observed

RETENTION AND RELEASE OF NICKEL IN NASAL MUCOSA
-the half-life of nickel release from the nasal mucosa was estimated to be about 3.5 years

Any other information on results incl. tables

Not Applicable

Applicant's summary and conclusion

Executive summary:

Torjussen and Andersen (1979) evaluated nickel concentrations in the nasal mucosa, blood and urine of current and retired nickel refinery workers and compared levels to those measured in control subjects. The main study group (n=318) consisted of nickel-exposed workers in the roasting/smelting department, electrolytic workers, and non-process workers who were said to be exposed to dry dust containing nickel subsulphide and oxide, aerosols of nickel sulphate and chloride, or miscellaneous nickel composites, respectively. Retired workers (n=15) and age-matched control subjects (n=57) were also included in the study. Blood, urine and nasal mucosa biopsy samples were collected between 1976-1977 and analyzed for total nickel using an atomic absorption spectrophotometer. In the nickel-exposed group, mean concentrations of nickel were 6.3 µg/L in plasma, 49.1 µg/L in urine, and 273.9 µg per 100g wet weight in nasal mucosa. Over 85% of the workers had nickel values that were above the normal limit in all three biological media. Levels were significantly lower in retired workers; mean concentrations of nickel were 2.9 µg/L in plasma, 11.3 µ/gL in urine, and 114.4 µg per 100g wet weight in nasal mucosa. The mean values of nickel in biological samples from the control group were significantly lower than levels in active and retired workers. Significant differences were also observed between the three worker categories. Additionally, measured nickel concentrations significantly correlated with the length of nickel exposure. The authors concluded that the amount of accumulated nickel in the nasal mucosa seems to be a more reliable parameter for expressing total nickel exposure to the upper respiratory tract than are the concentration of nickel in plasma or urine. This study presented numerous results for many different measurements, comparisons and correlations, thus providing a good dataset characterizing nickel concentrations in active and retired nickel workers. However, concurrent exposure to nickel in the air was not directly evaluated and thus it is difficult to correlate measured concentrations in biological media with occupational exposure. STUDY RATED BY AN INDEPENDENT REVIEWER