Registration Dossier

Administrative data

Endpoint:
specific investigations: other studies
Adequacy of study:
other information
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: 2.e: This study is sufficiently described and based on generally accepted scientific principles. GLP status is unknown. Therefore, this study should be considered as reliable with restrictions.

Data source

Reference
Reference Type:
publication
Title:
Structure-Activity Relationship of a Series of Sensory Irritants
Author:
Dudek B.R., Short R.D., Brown M.A. and Roloff M.V.
Year:
1992
Bibliographic source:
J. Toxicol. and Environm. Health., 37, 4, 511-518.

Materials and methods

Principles of method if other than guideline:
The authors estimated the potential sensory irritation of benzal chloride in Swiss-Webster mice exposed to a range of vapour concentrations during 10 min by following the decrease in their respiratory rate helped by a plethysmograph.
GLP compliance:
not specified
Type of method:
in vivo
Endpoint addressed:
respiratory irritation

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Alpha, Alpha-dichlorotoluene
- Analytical purity: 99% purchased from Aldrich chemical co.
No further data

Test animals

Species:
mouse
Strain:
Swiss Webster
Sex:
male

Administration / exposure

Route of administration:
inhalation: vapour
Vehicle:
not specified
Analytical verification of doses or concentrations:
yes
Duration of treatment / exposure:
Exposure period: 10 min
Frequency of treatment:
Once
Post exposure period:
None
No. of animals per sex per dose:
Four different concentrations unknown and four animal per dose
Control animals:
not specified

Results and discussion

Details on results:
The sensory irritation response measured was the average maximum percentage decrease in respiratory rate for four mice simultaneously exposed to vapor of the test chemical. The concentration that caused a 50 % decrease in the respiratory rate from baseline (RD 50) was calculated using least-squares regression analysis and gave a RD50 for benzal chloride of 27 ppm.

Applicant's summary and conclusion

Conclusions:
In the test conditions, the authors tested the sensory irritation potential of benzal chloride by following the decrease in the respiratory rate of mice exposed during ten minutes (RD50) to vapour of the substance. They estimated a RD50 around 27 ppm for benzal chloride.
However, at this level of information, no classification of specific target organ toxicity (here respiratory tract) could be done since the exposure period is only ten minutes.
Executive summary:

The authors tested the sensory irritation potential of benzal chloride by following the decrease in the respiratory rate of Swiss-Webster mice (weighing 23 -29 g) exposed during ten minutes (RD50) to vapours of the test substance. Respiratory frequency was monitored by a plethysmograph. The concentration that caused a 50 % decrease in the respiratory rate from baseline was calculated using least-squares regression analysis and gave a RD50 for benzal chloride of 27 ppm. This RD50 reflects the sensory irritation potential according to the authors.

No clear conclusion of the authors was drawn on the real sensory irritation potential of benzal chloride. However, this value may help for a weight of evidence for a classification as a specific target organ toxicant (here respiratory tract) following single exposure category 3.

This study is sufficiently described and is based on recognized scientific principles. Therefore, this study should be considered as reliable with restrictions and acceptable for assessment.