Trinickel disulphide

Exposure related observations in humans: other data

Administrative data

Endpoint:

exposure-related observations in humans: other data

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

not reported

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

This study had medium relevance to the Hazard or Risk Assessment of Ni3S2 and medium quality of exposure data. A detailed description of the scoring criteria and results can be found attached to IUCLID Section 7.10.5-Exposure Related Observations, Exposure Data Summary and Scoring.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Assessment of historical exposures in a nickel refinery in Norway.

Author:

Grimsrud TK, Berge SR, Norseth T, Andersen A

Year:

2000

Bibliographic source:

Scand J Work Environ Health 26, 338-345.

Materials and methods

Type of study / information:

Exposure matrices and breathing zone nickel concentrations for a cohort of Norwegian nickel refinery workers.

Endpoint addressed:

not applicable

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Utilize information on nickel species and exposure levels to generate a specific exposure matrix for epidemiologic analyses in a cohort of Norwegian nickel-refinery workers with a known excess of respiratory cancer.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Trinickel disulphide

EC Number:

234-829-6

EC Name:

Trinickel disulphide

Cas Number:

12035-72-2

Molecular formula:

Ni3S2

IUPAC Name:

(trinickel-1-ylidene)-1λ⁴-disulfene

Details on test material:

Exposure to sulfidic nickel was one of four groups of nickel compounds studied. The authors indicate that this is typically comprised of nickel subsulfide, but the measurements reported were only for sulfidic nickel as a group.

Method

Ethical approval:

not specified

Details on study design:

Stationary and personal air sampling conducted and reported during the period of 1973 to 1994 at a Norwegian nickel refinery. Retrograde calculations with multiplication factors (developed on the basis of reported changes in the metallurgical process and work environment) were also conducted to derived exposure level estimates for 1910-1972.

Exposure assessment:

measured

Details on exposure:

TYPE OF EXPOSURE: exposure to nickel dusts and aerosols

TYPE OF EXPOSURE MEASUREMENT: Area air sampling & Personal sampling. Nickel speciation conducted by a sequential leaching method.

EXPOSURE LEVELS: see table below

EXPOSURE PERIOD: sampling conducted over an average of 6.5 hours (personal) or 8 hours (static)

POSTEXPOSURE PERIOD: not applicable

DESCRIPTION / DELINEATION OF EXPOSURE GROUPS / CATEGORIES: exposures categorized by work type

Results and discussion

Results:

The average concentration of nickel was = 0.7 mg/m3 for all workers after 1978. Exposure levels for smelter and roaster day workers were
2-6 mg/m3 before 1970, while workers in nickel electrolysis and electrolyte purification were exposed to concentrations in the range of
0.15-1.2 mg/m3. The proportion of sulfidic Ni ranged from 0.01 to 0.72.

Applicant's summary and conclusion

Conclusions:

The mean concentration of measured total nickel in air in the different departments and periods did not exceed 1 mg Ni/ m3, and in most departments and periods it was lower than 0.5 mg Ni/m3. Sulfidic nickel was estimated to constitute about 72% of the total atmospheric nickel in the crushing and grinding department over the whole period of consideration (1910-1994). However, sulfidic nickel was only 5% or less of the total atmospheric nickel across the other departments and time frames, except teh calcining and smelting area (13%, 1978-1994) and the roasting area (15%, 1910-1977).

Executive summary:

Grimsrud et al. (2000) conducted an exposure assessment for a cohort of Norwegian nickel refinery workers based on personal air monitoring measurements from several different refinery departments. The exposure assessment involved developing a department-time-exposure matrix through a five-step process: (1) calculating average nickel air concentrations using measurement data from 1973-1994, (2) expanding the matrix to departments for which no data have been collected, (3) developing and applying multiplicative factors to the measured data to conduct retrograde exposure extrapolations, (4) determining the relative proportions of different nickel types, and (5) producing final exposure calculations based on estimates of total nickel and proportions of nickel species for all departments for all relevant time periods. Nickel speciation analyses from the 1990s were used to derive the relative distributions of nickel sulfides, oxides, sulfates, chlorides, and metallic nickel for the exposure assessment. For workers exposed after 1978 (the year a significant change was instituted in the refining process), the average breathing zone nickel concentration was ≤0.7 mg/m3. The highest nickel levels calculated were for smelter and roaster day workers from the 1950s and earlier, while the highest nickel concentrations estimated for hydrometallurgic processes were around 1 mg/m3 in the 1960s and earlier. Sulfidic nickel was estimated to constitute approximately 72% of the total atmospheric nickel in the crushing and grinding department over the whole period of consideration (1910-1994). However, sulfidic nickel was only 5% or less of the total atmospheric nickel across the other departments and time frames, except the calcining and smelting (13%, 1978-1994) and roasting areas (15%, 1910-1977). It should be noted that the sulfidic nickel was not further sub-speciated, so it was unclear what proportion of these measurements and estimates were comprised of nickel subsulfide versus other nickel sulfides. This exposure assessment was conducted in support of an epidemiological investigation on this same cohort of refinery workers. STUDY RATED BY AN INDEPENDENT REVIEWER.