2,2'-[(1-methylethylidene)bis(4,1-phenyleneoxy)]bisethyl diacetate

Endpoint summary

Description of key information

An in vitro skin irritation study and an in vitro eye irritation study have been conducted on Z-Acetate.  The substance was non-irritating to the eyes and non-irritating to the skin.

Additional information

An in vitro skin irritation study and an in vitro eye irritation study have been conducted on Z-Acetate. The substance was non-irritating to the eyes and non-irritating to the skin.

 

To assess the human epidermal irritation potential of the test article (Viscous liquid, Lot 565093, Purity 91.4%) using the reconstructed human epidermal tissue model, EpiDerm (EPI-200-SIT). The study was not conducted under GLP conditions. The test method was based on OECD Guideline No. 439 and EpiDerm Protocol MK-24-007-0023 Rev. 3/26/2012. Replicate sets of tissues were exposed to 30 uL of test article (n=3) or control (Positive: 5% SDS, Negative: 30 uL DPBS) agents (n=3) for a period 60 minutes at which time the surface of the tissues was thoroughly washed with Dulbecco’s Phosphate-Buffered Saline (DPBS) and incubated for 42 hours. Tissue viability was determined by the Thiazolyl blue (MTT) assay. The resulting optical densities (OD) were normalized to the mean of the negative control group. Viability data is presented as a percentage of the negative control group mean. The test is considered valid if the mean OD of the MTT test extractant for the DPBS treated negative control samples is >/= 1.0 and </= 2.5, the viability of the 60 minute 5% SDS treated positive control tissues is </= 20% of the negative control, and the standard deviation (SD) for the test samples is < 18%. Test article-treated tissues showed similar MTT viability compared to the negative control (100% viability). The results of the study indicate the test article is not irritating to the skin.

 

The corneal irritation and damage potential of the test article (Viscous liquid, Lot # 565093, Purity: 91.4%) was tested in the Bovine Corneal Opacity and Permeability test (BCOP). The study was performed in compliance with EPA GLP 40 CFR 160 and 792, FDA GLP 21 CFR 58, and OECD GLP (1997). The test method was based on OECD Guideline 437 (2013). Corneas (3/group) were prepared in cell culture media. The corneas were mounted in specially designed holders and incubated at 32 C for at least 1 hour prior to exposure. Corneas were treated with 0.75 mL of the test article or appropriate control (Positive: 100% ethanol, Negative: MEM) using the closed chamber method and incubated for an approximate 10 minute exposure period at 32 C. At the end of the exposure period, the corneas were rinsed with cell culture media and incubated for 2 hours in cell culture solution. Opacity was evaluated prior to treatment and immediately following the 2 hour incubation. Immediately following the opacity measurement, the cell culture media was replaced with 0.4% sodium fluorescein solution in Dulbecco’s Phosphate Buffered Saline (DPBS) and incubated for another 90 minutes. Following the 90 minute incubation, permeability was evaluated using a fluorescein method. The mean in vitro irritation score (IVIS) was calculated and the scores were classified according to protocol defined categories. For the test article, the IVIS= 1.21. The corrected mean opacity score was 1.00 (range -1 to 1), and the mean permeability score was 0.014 (range 0.002 to 0.02). Controls performed as expected. Based on the results of the test, the test article is expected to cause no significant irritation to the cornea (IVIS = 1.21).

Justification for classification or non-classification

Z-Acetate does not meet the CLP criteria for classification as a skin or eye irritant.