Reaction mass of 2,6-dimethylpyridinium chloride and 3-methylpyridinium chloride and 4-methylpyridinium chloride

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of 2,6-dimethylpyridinium chloride and 3-methylpyridinium chloride and 4-methylpyridinium chloride

EC Number:

941-122-2

Molecular formula:

not yet assigned

IUPAC Name:

Reaction mass of 2,6-dimethylpyridinium chloride and 3-methylpyridinium chloride and 4-methylpyridinium chloride

Test material form:

semi-solid (amorphous): gel

Remarks:

migrated information: paste

Test animals / tissue source

Species:

other: cattle eyes

Details on test animals or tissues and environmental conditions:

On the test day, fresh eyes were collected from the slaughterhouse and were transported in HBSS containing Pen/Strep on ice to the laboratories.
Immediately after arrival of the eyes, cornea preparation was initiated. The eyes were carefully examined for defects and any defective eyes were discarded.

Test system

Vehicle:

physiological saline

Controls:

yes

Amount / concentration applied:

The test item was suspended with physiological saline 0.9% NaCl (see 10.3) to gain a 20% concentration.
750 μL of the test item preparation or the control substance was introduced into the anterior chamber (closed-chamber method).

Duration of treatment / exposure:

After 4 hours incubation at 32 °C either the test substance or the control substance was removed and the epithelium washed at least three times with MEM (containing phenol red).

Number of animals or in vitro replicates:

3 corneas for the test item
3 corneas as negative controls treated with physiological saline 0.9% NaCl
3 corneas as positive control treated with imidazole 20% in physiological saline 0.9% NaCl

Details on study design:

After the equilibration period, the medium was removed from both chambers and replaced with fresh Complete RPMI. An initial opacity measurement was performed on each of the corneas using an opacitometer (MC2, Clermont, France). Three corneas with opacity readings approximately equivalent to the median opacity of all corneas were selected as negative-control corneas. The opacity of each cornea was read against an air-filled chamber and recorded. Corneas that have an initial opacity reading above 7 units were not dosed. The medium was removed from the anterior chamber and replaced with the test item or control.
The test item preparation or the control substance was introduced into the anterior chamber (closed-chamber method). After 4 hours ± 5 minutes incubation at 32 °C either the test substance or the control substance was removed and the epithelium washed at least three times with MEM (containing phenol red). Once the medium was free of test substance, the cornea was finally rinsed with complete RPMI (without phenol red). The anterior chamber was refilled with complete RPMI and an opacity measurement was performed.
After the opacity measurement the medium was removed from both chambers of the holder. The posterior chamber was refilled with fresh complete RPMI. Sodium fluorescein solution was added to the anterior chamber and the corneas were incubated for 90 minutes at 32 °C. Then the medium from the posterior chamber was removed and its optical density at 490 nm (OD490) was determined, using a spectrophotometer.

Results and discussion

In vivo

Results

Irritation parameter:

other: in vitro irritation score

Basis:

mean

Score:

196.34

Remarks on result:

other: The eye irritancy potential of Pyridine derivative 1 was investigated in the bovine corneal opacity and permeability assay.

Applicant's summary and conclusion

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Remarks:

Migrated information

Conclusions:

The following mean in vitro irritation score was calculated: 196.34
Therefore the test item is classified as corrosive / severe irritant to the eye (UN GHS Category 1).
The in vitro irritation score obtained with the positive control fell within the two standard deviations of the current historical mean and therefore this assay is considered to be valid.