Hydrogen cyanide

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Experimental data was reviewed by the ECETOC Task Force, author of the JACC Report No. 53, “Cyanides of Hydrogen, Sodium and Potassium, and Acetone Cyanohydrin (CAS No. 74-90-8, 143-33-9, 151-50-8 and 75-86-5)”, 2007. The report is a weight of evidence approach to an extensive body of literature, much of which was undertaken prior to development of guidelines. The report was peer reviewed by the scientific non-governmental organization (NGO), which judged the data to be reliable with restrictions.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Comparative acute toxicity of hydrogen cyanide and its salts

Author:

Ballantyne B

Year:

1984

Bibliographic source:

Proceedings of the Fourth Annual Chemical Defense Bioscience Review. Lindstrom R (ed) U.S. Army Medical Research Institute of Chemical Defense, MD

Reference 2

Reference Type:

publication

Title:

Acute percutaneous systemic toxicity of cyanides

Author:

Ballantyne B.

Year:

1994

Bibliographic source:

J Toxicol – Cut and Ocular Toxicol 13:249-262.

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Animals were exposed to a solution of cyanide via a specially-designed application vessel attached to the shaved and depilitated skin, intact and abraded. Observations were made of clinical signs and death, and time to these signs was noted.

GLP compliance:

not specified

Test type:

other:

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Hydrogen cyanide

EC Number:

200-821-6

EC Name:

Hydrogen cyanide

Cas Number:

74-90-8

Molecular formula:

CHN

IUPAC Name:

hydrogen cyanide

Test animals

Species:

rabbit

Strain:

not specified

Sex:

female

Administration / exposure

Type of coverage:

other: specially-designed phalanges for attachment of vessel containing HCN

Details on dermal exposure:

Exposed skin was depilitated, and a glass application vessel was attached using double-sided adhesive EEG electrode disks, cut in the middle to allow direct exposure. Solutions of cyanide were instilled into the well of the application chamber using a calibrated pipette, after which it was seals. A volume of 0.1 ml/kg was used. Animals were slightly restrained during the exposure, after which the cylinders were removed and the chambers washed out.

Duration of exposure:

up to 6 hours

No. of animals per sex per dose:

9-10

Control animals:

not specified

Details on study design:

The skin of some rabbits was abraded; the remaining rabbits' skin was intact.

Statistics:

95% Confidence Limits calculated

Results and discussion

Effect levels

Effect levels 1

Sex:

female

Dose descriptor:

LD50

Effect level:

ca. 2.34 mg/kg bw

95% CL:

> 2.02 - < 2.61

Remarks on result:

other: in abraded skin

Effect levels 2

Sex:

female

Dose descriptor:

LD50

Effect level:

ca. 6.89 mg/kg bw

95% CL:

> 6.43 - < 7.52

Remarks on result:

other: in intact skin

Mortality:

50%

Clinical signs:

no data

Body weight:

no data

Gross pathology:

no data

Other findings:

no data

Applicant's summary and conclusion

Interpretation of results:

very toxic

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The LD50 by the dermal route to rabbits with intact skin was 6.89 mg/kg bw. The LD50 in rabbits with abraded skin was 2.34 mg/kg bw. The onset of symptoms was rapid, within minutes.