the ADME Tox specialists
welcome to cyprotex

Ocular Irritation

Understand the potenial irritation to the eye of your individual ingredients / chemicals or finished products using our ocular irritation assay.

Ocular irritation is in our portfolio of in vitro topical services for the cosmetics/personal care, chemical or pharmaceutical industry. Cyprotex deliver consistent, high quality data under either GLP or non-GLP conditions.

Ocular irritation and its measurement in vitro

  • Cyprotex’s ocular irritation test is performed using MatTek's in vitro 3D EpiOcular™ model. Cyprotex are a MatTek-approved laboratory for performing these studies.
  • The EpiOcular™ tissue model consists of normal, human-derived epidermal keratinocytes that have been cultured to form a stratified, squamous epithelium which closely mimics the human corneal epithelium.
  • EpiOcular™ was developed by MatTek to create an in vitro (non-animal) alternative to the animal-based Draize Eye Irritation Test used in the cosmetics, personal care, household products, chemical, pharmaceutical, and biotech industries.
  • The EpiOcular™ eye irritation test model is currently undergoing ECVAM validation. Peer-reviewed publications have shown the EpiOcular™ eye irritation model achieves greater than 80% accuracy when compared with the Draize eye irritation test1.
  • The EpiOcular™ model is metabolically and mitotically active and produces the same cytokines involved in irritation and inflammation in vivo2.
  • A range of different test articles can be assessed including liquids, solids, semi-solids, pastes, gels, creams and waxes.
  • Cyprotex's ocular irritation test is based upon assessment of the cytotoxicity following exposure to a test chemical, typically at three time points. Cytotoxicity is expressed as a decrease in mitochondrial conversion of MTT to formazan.
Related Services
  Ocular Irritation
‘The EpiOcular-EIT, together with EpiOcular's long history of reproducibility and proven utility for ultra-mildness testing, make EpiOcular a useful model for addressing current legislation related to animal use in the testing of potential ocular irritants.’
3Kaluzhey Y et al., (2011) Altern Lab Anim 39(4); 339-364
Protocol +

Ocular irritation protocol

Method Available EpiOcular™ Eye Irritation Test (ET50 determination)
Model Used MatTek EpiOcular™ 3D human tissue model (other models available on request)
Number of Concentrations Typically 1 (depending on client needs)
Number of Replicates 1 - 3 (depending on assay and client needs)
Exposure Times 3 - 5 (depending on assay and client needs)
Controls Positive control = between 1-10% Benzalkonium chloride
Negative control = Sterile ultrapure water
Reference control = 10% Baby shampoo (optional)

IL-1α release (optional)
Histology (optional)
Addition endpoints available:
•cytokine release (IL-6, IL-8, TNFα)
•oxidative stress
•glutathione levels
•mitochondrial function

'Damage to the corneal epithelium resulting from exposure to chemicals and mixtures of chemicals may compromise tissue function, and can result in various effects ranging from mild irritation, to the loss of cornea transparency or blindness3.'
Data +

Data from the ocular irritation assay

Figure 1
Graph illustrating the cell viability over time using the EpiOcular™ EIT model. Error bars represent ± SEM (n=3).
Table 1
The ET50 and estimated Draize modified maximum average scores (MMAS) were determined using the cell viability data. Based on these results, the Predicted Potency was determined and compared to actual potency from various published reports.
Table 2
Proposed method for classification of ocular irritation potency.
ET50 = time taken for test article to reduce cell viability to 50% of negative control.
Figure 2
Structural similarity between the EpiOcular™ 3D tissue model and the rabbit cornea.

1Pfannenbecker U et al., (2013) Cosmetics Europe multi-laboratory pre-validation of the EpiOcular™ reconstituted human tissue test method for the prediction of eye irritation. Toxicology In Vitro 27(2); 619-626
2Thakur A et al., (1997) Modulation of cytokine production from an EpiOcular corneal cell culture model in response to Staphylococcus aureus superantigen. Aust N Z J Ophthalmol 25(4); 43-45.
3Kaluzhey Y et al., (2011) Development of the EpiOcular(TM) eye irritation test for hazard identification and labelling of eye irritating chemicals in response to the requirements of the EU cosmetics directive and REACH legislation. Altern Lab Anim 39(4); 339-364

This website was last updated
on 21st July 2014
This website is intended to assist investors, industry participants, customers and employees to understand Cyprotex’s global operations and ambitions.
Certain information and detail is disclosed in the interest of compliance of AIM Rule 26.