Charcoal

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

other: Data sharing dispute

Adequacy of study:

key study

Study period:

2010-06-17 to 2010-08-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study was performed according to ICCVAM recommended HET-CAM Method Protocol (Nov. 2006)

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: According to ICCVAM recommended HET-CAM Method Protocol (Nov. 2006)

Deviations:

no

Principles of method if other than guideline:

The HET-CAM method is an alternative in vitro procedure that predicts the ocular irritative or corrosive potential of a test substance by observing the development of irritancy effects in the chicken egg chorioallantoic membrane (CAM). The CAM is a vital vascular fetal membrane with a closed blood vessel system. Given the high vascularity of this membrane, this method is proposed to provide information on the effects that may occur in the conjunctiva (a highly vascularised ocular structure) following exposure to a test substance.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Charcoal

EC Number:

240-383-3

EC Name:

Charcoal

Cas Number:

16291-96-6

Molecular formula:

Not applicable for UVCB substances

IUPAC Name:

Charcoal

Details on test material:

Name: Charcoal (Probe 1: C-Fix = 73.3%)
Batch No.: 19062009 1PP
Appearance: Charcoal typic
CAS No.: 16291-96-6
EINECS No.: 240-383-3
Purity: C-Fix: 73.3%
Date of expiry: December 2030
Storage conditions: Room temperature 20 ± 5 °C, keep away from humidity

Test animals / tissue source

Species:

other: not applicable (this is an in vitro test)

Strain:

other: not applicable (this is an in vitro test)

Details on test animals or tissues and environmental conditions:

not applicable (this is an in vitro test)

Test system

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

approx. 50 mg

Duration of treatment / exposure:

300 sec (5 min)

Observation period (in vivo):

300 sec (5 min)

Number of animals or in vitro replicates:

not applicable (this is an in vitro test)

Details on study design:

Test system:
The HET-CAM was carried out with Lohmann Selected Leghorn chicken's eggs. The eggs were obtained 9 days before the start of the test. Eggs were incubated at 38.5 °C, 58.8% humidity for nine days, periodically rotated. On day eight the eggs were candled and non-viable eggs were discarded. The rest of the eggs were placed upwards in the incubator for another day.

Test groups:
Negative control: 0.9% NaCl, on 3 eggs; 300 μL each
Positive control: 1% SDS solution in deionized water, on 3 eggs; 300 μL each
Positive control: 0.1 N NaOH, on 3 eggs; 300 μL each
Test item: Neat charcoal about 50 mg of <100 µm size

Experimental performance:
After application of test item, negative and positive control, the eggs were observed for a period of 300 sec. Three endpoints were observed. The time when that particular endpoint was observed was noted. The three endpoints were:
• hemorrhage
• blood vessel lysis
• coagulation

Results and discussion

In vivo

Results

Irritation parameter:

overall irritation score

Basis:

other: Provided on the above section 'any information on materials and methods incl. tables'

Time point:

other: 300 sec

Score:

0

Max. score:

21

Reversibility:

not specified

Remarks on result:

other: Result: non - irritant

Irritant / corrosive response data:

The irritation score (IS) for charcoal (IS:0.0) was not different from the negative control (IS: 0). The positive controls (0.1N NaOH, and 1% SDS) caused values (IS: 19.99 and 11.25, respectively) that fell within the classification of severely irritating to the eye.

Other effects:

not applicable

Any other information on results incl. tables

not applicable

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

It can be stated that under the experimental conditions reported, charcoal did not exhibit any ocular irritating potential in vitro.

Executive summary:

This in vitro study (HET-CAM) was performed to assess the irritating potential of charcoal (Probe 1: C-Fix = 73.3%). Charcoal was brought onto the surface of the chorioallantoic membrane (CAM) of 6 freshly laid hen’s eggs which had been incubated at 38.5 °C and 58 - 60% humidity for 9 days. The occurrence of vascular injection, hemorrhage, and coagulation was observed and recorded over a period of 5 min after application of the test item. Physiological sodium chloride solution was used as negative control. The negative control showed no irritating effect on the blood vessels of the CAM (mean irritation score, IS = 0.00). Solutions of SDS (1%) and NaOH (0.1 N) were used as positive controls. The positive controls induced a severe irritation on the blood vessels with IS of 11.25 and 19.99, respectively. The test item, charcoal (Probe 1: C-Fix = 73.3%) showed no effects on the blood vessels of the CAM. The calculated mean IS was 0.00. In conclusion, it can be stated that under the experimental conditions used in this study, the test item, charcoal (Probe 1: C-Fix = 73.3%) had no irritation potential.