Calcium acetylide

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1933

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

publication

Title:

Experimentelle Untersuchung über die Frage der Organschädigung nach Gasnarkose (Acetylen, Äthylen und Stickstoff)

Author:

Franken, H., Miklos, L.

Year:

1933

Bibliographic source:

Zentralblatt für Gynäkologie Nr 42, p. 2493-2498

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Possible organ damage from the administration of acetylene at anesthetic concentrations has been evaluated in rats, mice, guinea pigs, rabbits, and dogs. Animals were exposed to acetylene in oxygen for 0.5 - 2h per day for up to 93 days; no guideline available at that time

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Acetylene

EC Number:

200-816-9

EC Name:

Acetylene

Cas Number:

74-86-2

Molecular formula:

C2H2

IUPAC Name:

acetylene

Test material form:

other: gas

Test animals

Species:

rat

Strain:

not specified

Sex:

not specified

Administration / exposure

Route of administration:

inhalation: gas

Type of inhalation exposure:

whole body

Vehicle:

oxygen

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

0,5 - 2 h/d

Frequency of treatment:

daily up to 93 days

Doses / concentrations

Dose / conc.:

25 000 ppm (nominal)

Remarks:

Doses / Concentrations:
25%

No. of animals per sex per dose:

2 - 47

Control animals:

yes

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Effect levels

Key result

Dose descriptor:

NOAEC

Effect level:

250 000 ppm

Based on:

test mat.

Sex:

not specified

Basis for effect level:

gross pathology

Remarks on result:

not determinable

Remarks:

no NOAEC identified

Target system / organ toxicity

Key result

Critical effects observed:

not specified

Any other information on results incl. tables

In treated animals that survived to termination, no evidence of cellular injury to the parenchymatous cells of the heart, lungs, liver, kidneys, or spleen was reported. However, capillary hyperemia of the liver, kidneys and spleen was observed in some rats exposed to 25%. This effect was observed until at least the second day after the last exposure to the gas but was not evident in animals killed later (up to 5 days after the last exposure). Since capillary hyperemia was not observed in rats exposed to higher concentrations of acetylene, it does not appear to be test-material related.

Applicant's summary and conclusion

Conclusions:

Repeated exposure of rats to a concentration of 25% acetylene (1h/day for up to 93 days) did not cause any organ toxicity.

Executive summary:

In a non-guideline subchronic inhalation toxicity study, acetylene was administered to 2 -47 rats/sex/concentration by whole body exposure at concentrations of 0 and 25,000 ppm daily for 1 hour for up to 93 days.

In treated animals that survived to termination, no evidence of cellular injury to the parenchymatous cells of the heart, lungs, liver, kidneys, or spleen was reported. However, capillary hyperemia of the liver, kidneys and spleen was observed in some rats exposed to 25%. This effect was observed until at least the second day after the last exposure to the gas but was not evident in animals killed later (up to 5 days after the last exposure). Since capillary hyperemia was not observed in rats exposed to higher concentrations of acetylene, it does not appear to be test-material related.

Based on the results of this study, the NOAEC is considered to be 25,000 ppm.