Registration Dossier

Administrative data

Description of key information

A standard skin irritation test performed with strontium chromate showed no signs of skin irritation.
Case reports and industrial health surveys indicate eye irritation after human exposure to chromate solutions. However, only mild eye irritation was observed in a standard animal test with strontium chromate.
Respiratory irritation (mainly nasal irritation and perforated septum) has traditionally been common among chromate exposed workers.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Additional information

No signs of skin irritation were observed in an unpublished standard rabbit OECD test carried out with strontium chromate. This study can also be regarded as a key study for zinc tetraoxychromate. Cases of skin ulceration were, however, reported at a strontium chromate plant with poor hygienic conditions. This report also indicated high chromium concentrations in biomonitoring samples. No signs of skin irritation/corrosion were observed among lead chromate workers in the same study. As only one report from a single factory was available, and it did not clearly describe e.g. what other exposures the workers had, it was concluded that the data obtained in the guideline animal skin irritation test was more reliable.

Soluble chromates are well-known skin corrosive substances, but there are no published animal studies on skin irritation caused by sparingly soluble chromates.

No sparingly soluble chromates are currently classified for skin irritation/corrosion.

Therefore, based on the similar solubility properties of zinc tetraoxychromate and strontium chromate, the standard animal test with strontium chromate was selected as the critical study, and according to the results of the test, no classification is suggested for skin irritation for zinc tetraoxychromate.

Case reports and industrial health surveys indicate eye irritation after human exposure to solutions of highly soluble chromates. However, strontium chromate has been tested for eye irritation in a standard OECD eye irritation test performed in rabbits. Strontium chromate caused only slight eye irritation, and according to the classification criteria it should not be classified as an eye irritant. Based on the similar solubilities of zinc tetraoxychromate and strontium chromate, the results of the eye irritation test can be used for read-across. Therefore, zinc tetraoxychromate is not suggested to be clasified for eye irritation. This conclusion is supported by the fact that no case reports on eye irritation caused by sparingly soluble chromates have been found in the literature.

There are no animal data on respiratory irritation caused by chromates. At a strontium chromate plant, with poor hygienic conditions, cases of rhinitis and nasal ulceration were observed. In addition, this report (also referred to under skin irritation) showed increased chromium levels in biomonitoring samples. Also in studies examining signs of respiratory symptoms of chrome platers, the numbers of nasal perforation or ulceration have traditionally been increased, and these have generally been recognized as typical effects of soluble chromates. As there are no standard test methods available for respiratory irritation, and only limited data available, classification for respiratory irritation is suggested based on weight of evidence from occupational reports on various chromates.


Effects on respiratory irritation: irritating

Justification for classification or non-classification

No classification is suggested for skin or eye irritation. This is justified by standard OECD rabbit tests performed with strontium chromate.

Classification for respiratory irritation is suggested for zinc tetraoxychromate based on occupational findings (strontium chromate and other chromates).