A dried sludge product resulting from the treatment process of domestic wastewater. The exact processes followed for the production of the dried sludge are: Preliminary + secondary treatment of the wastewater stream, thickening, dehydration and drying of the excess sludge.

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15.09.2021-16.09.2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

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)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

A dried sludge product resulting from the treatment process of domestic wastewater. The exact processes followed for the production of the dried sludge are: Preliminary & secondary treatment of the wastewater stream, thickening, dehydration and drying of the excess sludge.

EC Number:

943-834-9

Molecular formula:

Not applicable for UVCB substances

IUPAC Name:

A dried sludge product resulting from the treatment process of domestic wastewater. The exact processes followed for the production of the dried sludge are: Preliminary & secondary treatment of the wastewater stream, thickening, dehydration and drying of the excess sludge.

Test animals / tissue source

Species:

cattle

Strain:

other: Bovine

Test system

Vehicle:

physiological saline

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

The test item was tested as suspension prepared from test item at 20% concentration in a 0.9% sodium chloride solution.
2g of the test item was suspended in 10 mL of 0.9% sodium chloride solution.

Duration of treatment / exposure:

4 hours

Duration of post- treatment incubation (in vitro):

1.5 hours

Number of animals or in vitro replicates:

3

Details on study design:

Scheme
Selection of corneas, mounting in holders → incubation with EMEM 1hour (32 ± 1°C) → removed EMEM, measurement of baseline opacity → treatment by positive and negative control substances and test item (incubation 4 hours) → washing of epithelium, measurement of opacity after application → application of sodium fluorescein (5 mg/ml), incubation 1.5 hour (32 ± 1°C) → measurement of absorbance (490 nm).

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Value:

1

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The study met all the acceptance criteria for positive and negative controls. The In Vitro Irritancy Score (IVIS) for test item, Dried Sludge from domestic wastewater was 1.00.
This value of IVIS is ≤ 3 therefore the classification of test item effect according to UN GHS criteria for eye irritation or serious eye damage is: No category.

Executive summary:

The test item, Dried Sludge from domestic wastewater, was tested for the potential to cause ocular corrosivity or severe irritancy, as measured by its ability to induce opacity and increased permeability in an isolated bovine cornea. The test was performed according to OECD Test Guideline No. 437 (2017) and Method B.47 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, Commission Regulation (EU) 2017/735, Adopted 14th February 2017.

The testing was performed on three groups of corneas: test item treatment group, positive control group (20% w/v imidazole in 0.9% NaCl solution) and negative control group (0.9% NaCl solution). Three corneas per group were used.

The open-chamber method was used, because the test item solution was not applicable by micropipette. The test item (enough to completely cover the cornea) was applied directly to the epithelial surface of the cornea using inject syringe.
Corneas were exposed for 4 hours.

The opacity and permeability of each cornea were measured. The In Vitro Irritancy Score (IVIS) was calculated from the values of opacity and permeability.

The study met all the acceptance criteria for positive and negative controls. The In Vitro Irritancy Score (IVIS) for Dried Sludge from domestic wastewater was 1.00.

This value of IVIS is ≤ 3 therefore the classification of test item effect according to UN GHS criteria for eye irritation or serious eye damage is: No category.