Molybdenum, N,N-bis(C11-14-branched and linear alkyl)carbamodithioate oxo thioxo complexes

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

25 August 2017 to 14 September 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

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)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU method B.47 (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:

Bis(C11-14-branched and linear alkyl)dithiocarbamic acid

Molecular formula:

N/A

IUPAC Name:

Bis(C11-14-branched and linear alkyl)dithiocarbamic acid

Constituent 2

Reference substance name:

Molybdenum, bis(C11-14 branched and linear alkyl)carbamodithioato-.kappa.S,.kappa.S')oxodi-thioxothioxodi-

Molecular formula:

N/A

IUPAC Name:

Molybdenum, bis(C11-14 branched and linear alkyl)carbamodithioato-.kappa.S,.kappa.S')oxodi-thioxothioxodi-

Constituent 3

Reference substance name:

Molybdenum, bis(C11-14 branched and linear alkyl)carbamodithioato-.kappa.S,.kappa.S')dioxodi-thioxodi-

Molecular formula:

N/A

IUPAC Name:

Molybdenum, bis(C11-14 branched and linear alkyl)carbamodithioato-.kappa.S,.kappa.S')dioxodi-thioxodi-

Constituent 4

Reference substance name:

Molybdenum, bis(N,N-di-C11-14 branched and linear alkyl)carbamodithioato-.kappa.S,.kappa.S')-oxodioxo-thioxodi-

Molecular formula:

N/A

IUPAC Name:

Molybdenum, bis(N,N-di-C11-14 branched and linear alkyl)carbamodithioato-.kappa.S,.kappa.S')-oxodioxo-thioxodi-

Test material form:

liquid

Specific details on test material used for the study:

CAS RN: 906665-74-5
Purity: > 90%
Physical state/Appearance: Brown viscous liquid

Test animals / tissue source

Species:

cattle

Strain:

not specified

Details on test animals or tissues and environmental conditions:

Eyes from adult cattle (typically 12 to 60 months old) were obtained from a local abattoir as a by-product from freshly slaughtered animals. The eyes were excised after slaughter and placed in Hanks’ Balanced Salt Solution (HBSS) supplemented with antibiotics (penicillin at 100 IU/mL and streptomycin at 100 µg/mL), and transported to the test facility over ice packs on the same day of slaughter. The corneas were prepared immediately on arrival.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

0.75 mL of the test item or control items were applied to the appropriate corneas

Duration of treatment / exposure:

Each holder was incubated, anterior chamber uppermost, at 32 ± 1 ºC for 10 minutes

Duration of post- treatment incubation (in vitro):

120 minutes

Number of animals or in vitro replicates:

Three

Details on study design:

Preparation of Corneas
The cornea from each selected eye was removed leaving a 2 to 3 mm rim of sclera to facilitate handling, and the iris and lens were peeled away from the cornea. The isolated corneas were immersed in a dish containing HBSS until they were mounted in Bovine Corneal Opacity and Permeability (BCOP) holders. The chambers of each BCOP holder were filled with complete Eagle’s Minimum Essential Medium (EMEM) without phenol red, plugged and incubated at 32 ± 1 ºC for 60 minutes. At the end of the incubation period each cornea was examined for defects. Only corneas free of damage were used.

Selection of Corneas and Opacity Reading
The medium from both chambers of each holder was replaced with fresh complete EMEM and a pre treatment opacity reading was taken for each cornea using a calibrated opacitometer. The average opacity for all corneas was calculated.

Treatment of Corneas
The EMEM was removed from the anterior chamber of the BCOP holder and the test item or control items were applied to the appropriate corneas and each holder was incubated at 32 ± 1 ºC for 10 minutes.
At the end of the exposure period the test item and control items were removed from the anterior chamber and the cornea was rinsed with fresh complete EMEM containing phenol red before a final rinse with complete EMEM without phenol red. The chamber was then refilled with fresh complete EMEM without phenol red. A post treatment opacity reading was taken and each cornea was visually observed.
The holders were incubated at 32 ± 1 ºC for 120 minutes. After incubation, the medium from both chambers was replaced with fresh complete EMEM and a final opacity reading was taken. Each cornea was visually observed.

Application of Sodium Fluorescein
Following the final opacity measurement the permeability of the corneas to sodium fluorescein was evaluated. The medium was removed and replaced with sodium fluorescein solution (4 mg/mL). The dosing holes were plugged and the holders incubated, anterior chamber uppermost, at 32 ± 1 ºC for 90 minutes.

Permeability Determinations
After incubation the medium in the posterior chamber of each holder was decanted and retained.
360 µL of media representing each cornea was dispensed into the appropriate wells of a pre labeled 96 well plate. The optical density was measured (quantitative viability analysis) at 492 nm (without a reference filter) using the Labtech LT-4500 microplate reader and LT-com software.

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Value:

1.2

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

Corneal Epithelium Condition
The corneas treated with the test item were clear post treatment and clear post incubation. The corneas treated with the negative control item were clear post treatment and post incubation. The corneas treated with the positive control item were cloudy post treatment and post incubation.

Criteria for an Acceptable Test
The positive control In Vitro Irritancy Score was within the historical range of 31.6 to 58.7; the positive control acceptance criterion was satisfied. The negative control gave opacity of ≤3.0 and permeability ≤0.077; the negative control acceptance criteria were satisfied.

Test Item
The in vitro irritancy score of the test item was 1.2, based on this result, the test item in not an eye irritant.

Any other information on results incl. tables

In Vitro Irritancy Score

Treatment	In Vitro Irritancy Score
Test Item	1.2
0.9% (w/v) Sodium Chloride (Negative Control)	0.8
Neat Ethanol (Positive Control)	43.1

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of the study, the test material has been determined to be non-irritating to the eye.

Executive summary:

In a study performed to the standardized guidelines OECD 437 and EU Test Method B.47., under GLP conditions, the undiluted test item was applied for 10 minutes followed by an incubation period of 120 minutes. Negative (0.9% (w/v) Sodium Chloride) and positive (Neat Ethanol) control items were tested concurrently. The two endpoints, decreased light transmission through the cornea (opacity) and increased passage of sodium fluorescein dye through the cornea (permeability) were combined in an empirically derived formula to generate an In Vitro Irritancy Score (IVIS). Based on the results of the BCOP test, the test item is not irritant to eye, not requiring classification to UN GHS or EU CLP.