Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records
Reference
Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2018
Reliability:
1 (reliable without restriction)
Qualifier:
according to
Guideline:
OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)
GLP compliance:
yes
Test system:
artificial membrane barrier model
Source species:
human
Cell type:
non-transformed keratinocytes
Cell source:
other: episkin
Source strain:
not specified
Vehicle:
physiological saline
Control samples:
yes, concurrent negative control
yes, concurrent positive control
Amount/concentration applied:
50 µL
Duration of treatment / exposure:
Exposure times of 3, 60±5 and 240±5 minutes
Number of replicates:
2
Type of coverage:
open
Preparation of test site:
not specified
Vehicle:
physiological saline
Controls:
yes, concurrent positive control
yes, concurrent negative control
Amount / concentration applied:
50 µL
Duration of treatment / exposure:
Exposure times of 3, 60±5 and 240±5 minutes
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
240 minutes
Value:
ca. 53
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid

TwoMain Assays were performed.

In the firstMain Assay, the mean Optical Density of Blank Controls was 0.037, lower than the maximum acceptable value (0.1). All negative control mean OD values gave the expected baseline value and variability, in agreement with guideline indications. According to the method, each negative control mean value is considered the baseline value for the concurrent treatment series, thus they represent 100% of cell viability. Positive control results indicated an appropriate cell death with an acceptable relative cell viability (1% of the negative control value).

Based on the stated criteria, the experiment was accepted as valid.

The test item did not induce cell death in any replicate, after 3 or 60 minutes of treatment time. Marked reduction of mean percent viability was noted at 240 minute treatment time.

Each mean cell viability, after the concurrent blank subtraction, was as follows:

Treatment time (minutes)              Mean cell viability (%)

3                                                 113

60                                                140

240                                               34

Intra-replicate variability was acceptable with a difference of viability between the two replicates lower than 30%, for all treatment times.

Results obtained in this experiment using the longest treatment time (240 minutes) should be considered borderline, as viability values of the replicated tissues were one above and one below the threshold value. Moreover, test item features and results obtained for eyes corrosion are predictive of no corrosive potential for the skin. Based on these considerations, a Main Assay II was performed. In this second experiment, a slight reduction of mean percent viability was noted at all treatment times.

Each mean cell viability, after the concurrent blank subtraction, was as follows:

Treatment time (minutes) Mean cell viability (%)

3 61

60 80

240 53

Also in this experiment all the acceptability criteria were met with the exception that after 60 minutes of treatment intra-replicate variability slightly exceeded the maximum acceptable value (Δ%= 35.8). However, the results obtained with the replicate tissues were both predictive of no corrosive potential and thus were considered acceptable.

For each treatment time, the average of viability values obtained in the two experiments was calculated and results obtained were as follows:

Treatment time (minutes) Mean cell viability (%) - two experiments

3 87

60 110

240 44

Based on the results obtained, the test item TERPENIC BASE is identified as non-corrosive to the skin.

Interpretation of results:
GHS criteria not met
Conclusions:
The potential of the test item TERPENIC BASE to be corrosive to the skin was investigated through an in vitro skin corrosion study, using a commercial reconstructed human epidermis (RhE) model named EPISKIN™.
The blank, negative and positive controls gave acceptable results at all treatment times, thus the study was accepted as valid.
After 240 minutes of treatment, a reduction of mean percent viability to 34% of the concurrent negative control value was noted.

Based on this result, the test item TERPENIC BASE is identified as non-corrosive to the skin.
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records
Reference
Endpoint:
eye irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Qualifier:
according to
Guideline:
OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)
GLP compliance:
yes
Species:
cattle
Strain:
other: Bos primigenius Taurus (fresh bovine corneas)
Vehicle:
Hank's balanced salt solution
Controls:
yes, concurrent positive control
Irritation parameter:
in vitro irritation score
Run / experiment:
1
Value:
> 3.88 - < 5.23
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid
Interpretation of results:
study cannot be used for classification
Endpoint conclusion
Endpoint conclusion:
no study available

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Additional information

Justification for classification or non-classification

The OECD 437 study assay was performed obtaining a result of a calculated mean IVIS = 4.43.

According to OECD Guideline no. 437 (Oct. 2017), a substance with an IVIS > 3 and ≤ 55 induces effects on the cornea, that cannot be classified in an UN GHS Category with the BCOP test only. In this case no prediction can be made, so it has been classified as Eye Irrit. 2 (H319).