Resin acids and Rosin acids, reaction products with formaldehyde, calcium salts

Endpoint summary

Description of key information

No irritating effects were observed in validated in-vitro studies for skin and eye irritation. Studies were performed under GLP and according to OECD testing guidelines in case of the Epiderm and BCOP assay. The EpiOcular assay has undergone in-house validation to identify normal irritants.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The potential of Resin acids and rosin acids, reaction products with formaldehyde, calcium salts to cause dermal irritation was assessed by a single topical application of 25 μL bulk volume (about 5 mg) of the undiluted test substance to a reconstructed three dimensional human epidermis model (EpiDerm™) (OECD 439, GLP). Three EpiDerm™ tissue samples were incubated with the test substance for 1 hour followed by a 42-hours post-incubation period. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/ post-incubation using a colorimetric test. The reduction of mitochondrial dehydrogenase activity, measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the testsubstance treated epidermal tissues is compared to that of negative control tissues. The quotient of both values indicates the relative tissue viability. The EpiDerm skin irritation test showed the following results: The test substance is not able to reduce MTT directly. The mean viability of the test-substance treated tissues determined after an exposure period of 1 hour with about 42 hours post-incubation was 102%. Based on the observed results it was concluded, that Resin acids and rosin acids, reaction products with formaldehyde, calcium salts does not show a skin irritation potential in the EpiDerm™ skin irritation test under the test conditions chosen.

The potential of Resin acids and rosin acids, reaction products with formaldehyde, calcium salts to cause serious damage to the eyes was assessed by a single topical application of the undiluted test substance to the epithelial surface of isolated bovine corneas (OECD 437, GLP). The solid test substance could not be prepared as a homogeneous 20% preparation in de-ionized water. Therefore 100 mg of the undiluted test substance was applied directly to the epithelial surface of the cornea covering the whole surface of the cornea. Three corneas were treated with the test substance for an exposure period of 4 hours. Corneal opacity was measured quantitatively as the amount of light transmission through the cornea. Permeability was measured quantitatively as the amount of sodium fluorescein dye that passes across the full thickness of the cornea. Both measurements were used to calculate an In Vitro Irritancy Score of the test substance relative to the control corneas. Mean opacity and permeability scores were comparable to control incubations, whereas clear effects were observed for the positive control substance. The test substance is therefore not highly irritating to eyes.

To assess the potential for non-severe irritancy, the EpiOcular assay was performed. For this assay, no OECD testing guideline is available. The study was performed according to the methods described in the following publications: - MatTek Corporation, Ashland, MA 01721, USA: EpiOcularTM human cell construct: Procedure details, Version 3.1a of February 10, 2010. - Harbell J.W. et al. (2009): COLIPA Program on Optimization of Existing In Vitro Eye Irritation Assays for Entry into Formal Validation: Technology Transfer and Intra/Inter Laboratory Evaluation of EpiOcular Assay for Chemicals. Poster # 378, Society of Toxicology, March 2009. Two EpiOcular™ tissue samples were incubated with the test substance for 90 minutes followed by a 18-hours post-incubation period. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/post-incubation using a colorimetric test. The reduction of mitochondrial dehydrogenase activity, measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the test substance treated epidermal tissues is compared to that of negative control tissues. The quotient of the values indicates the relative tissue viability. The EpiOcular™ eye irritation test showed the following results: The test substance is not able to reduce MTT directly. The mean viability of the test-substance treated tissues was 99%. Based on the observed results it was concluded, that Resin acids and rosin acids, reaction products with formaldehyde, calcium salts does not show an eye irritation potential in the EpiOcular™ eye irritation test under the test conditions chosen.

Justification for selection of eye irritation endpoint:
arbitrary, both studies needed.

Justification for classification or non-classification

Dangerous Substance Directive (67/548/EEC)

The available in-vitro studies are considered reliable and suitable for classification purposes under 67/548/EEC. As a result the substance is not considered to be classified for skin or eye irritation under Directive 67/548/EEC, as amended for the 31st time in Directive2009/2/EG.

 

Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance is not considered to be classified for skin or eye irritation under Regulation (EC) No. 1272/2008, as amended for the third time in Directive EC 618/2012.