Reaction mass of chromium (+ 3) hydroxide sulfate and sodium sulfate

Health surveillance data

Administrative data

Endpoint:

health surveillance data

Type of information:

other: literature reviews

Adequacy of study:

weight of evidence

Study period:

Variable

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Critical studies are summarized in three literature reviews

Data source

Reference

Reference 1

Reference Type:

review article or handbook

Title:

Health risk assessment report for metallic chromium and trivalent chromium

Author:

Finnish Institute of Occupational Health

Year:

2006

Bibliographic source:

Published by the International Chromium Development Association

Reference 2

Reference Type:

review article or handbook

Title:

Toxicological profile for chromium

Author:

Agency for Toxic Substances and Disease Registry

Year:

2000

Bibliographic source:

US Dept of Health and Human Services, Public Health Service, ATSDR

Reference 3

Reference Type:

review article or handbook

Title:

The toxicity of chromium and inorganic chromium compounds

Author:

Health and Safety Executive

Year:

1989

Bibliographic source:

HSE Toxicity review 21

Materials and methods

Study type:

other: various study types are summarised

Endpoint addressed:

not applicable

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Summary of literature reports investigating various endpoints

GLP compliance:

not specified

Remarks:

: not appicable

Test material

Test material information

Constituent 1

Reference substance name:

Chromium hydroxide sulphate

EC Number:

235-595-8

EC Name:

Chromium hydroxide sulphate

Cas Number:

12336-95-7

Molecular formula:

CrHO5S

IUPAC Name:

chromium hydroxide sulphate

Constituent 2

Reference substance name:

not applicable

IUPAC Name:

not applicable

Details on test material:

In occupational studies, it is often difficult to separate exposure of chromium (III) from chromium (VI).

Method

Details on study design:

Various study types are summarised

Results and discussion

Results:

See below.

Any other information on results incl. tables

Kinetics The leather tanning industry typically uses trivalent chromium in the form of basic chromium sulphates. In one study, tannery workers exposed to basic chromium sulphate or Cr bound to leather dust exhibited significantly higher chromium concentrations (4 ug/g chromium in hair, 1.7 ug/g creatinine chromium in urine and 25 mg/dm3 chromium in sweat) than controls (FIOH review, 2006). In another study, the highest concentration of chromium in serum and urine samples taken from three groups of tannery workers (highly exposed, moderately exposed and controls) were seen in workers with the highest exposure. Exposure to basic chromium sulphate in four different tanneries showed that Monday morning urinary chromium concentrations were clearly lower than that of Friday afternoon. According to an industry report, urinary chromium concentrations in workers of one electroplating shop employing trivalent chromium varied from 0.23 to 0.85 ug/g creatinine. Additional studies on tannery workers include one conducted with 24 polishers (12/sex) of chrome tanned, dried leather with 2-20 years of employment in a Polish tannery and a control group of 21 office workers. The average concentration of leather dust was reported as 2 mg/m3 with airborne concentrations of 0.1 mg/m3 Cr (III). Health effects Chronic inflammation in the upper airways, especially in the pharynx, was seen in tannery workers but the authors did not show evidence to exclude other potential causes such as microbial toxins or finishing chemicals in the leather (FIOH, 2006). No increase in the prevalence of respiratory illness was found in a study of 128 workers from two factories that produced water-soluble chromium (III) sulphate or insoluble chromium (III) oxide, or in 106 workers at a factory that produced these compounds where workroom levels were 1.99 mg Cr (III)/m3 (ATSDR, 2000). No indication was found that exposure to chromium (III) resulted in stomach disorders in workers employed in two factories that produced chromium (III) oxide or chromium (III) sulfate. An early report of cases of chrome ulcers in leather tanners noted that the only workmen in tanneries who suffered chrome holes were those who handled dichromate salts (ATSDR review, 2000). No increase in chromosomal aberrations was observed in 17 tannery workers exposed primarily to water-soluble trivalent chromium compounds, as compared with controls (ATSDR review, 2000). Workers handling hides soaked in chromium (III) sulphate solution during leather tanning had increased levels of chromium in the blood and urine. Urinary chromium remained above normal in these workers even after a 40-day vacation (HSE review, 1989). Another study of Canadian tannery workers from four plants, with an average concentration of 1.7 ug Cr/m3, indicated that workers had significant three- and four-fold increases in serum and urine chromium, respectively. German workers exposed to trivalent chromium as highly water-soluble chromium sulphate had higher blood and urine chromium levels compared to an unexposed control group (HSE review, 1989).

Applicant's summary and conclusion

Conclusions:

Elevated chromium levels in urine and blood have been seen with occupational exposure to water-soluble chromium (III) compounds.

Executive summary:

Based on the studies reviewed, occupational exposure to highly water-soluble Cr (III) compounds in leather tanning resulted in significantly elevated blood and urine chromium levels. The principal exposure route(s) responsible for this chromium absorption has not been properly identified.