Development of a novel ex vivo model for chemical ocular toxicity assessment and its applicability for hair straightening products.

This study developed an air-liquid interface (ALI) corneal model using explants bovine eyes for ocular toxicity assessment of ten chemicals and seven hair straightening mixtures. It was successfully maintained physiologically viable and normal for six days. Both eye damage (GHS cat. 1) and irritating (GHS cat. 2) chemicals induced corneal injury in our model. However, cat. 2 irritants triggered moderate damage when compared to cat. 1 agents, which induced a marked cytotoxicity profile. The mixtures were also able to trigger viability reduction associated with histopathological changes in the corneal tissues, especially when the exposure was via aerosol particles. Thus, the chemical exposure microenvironment simulation seemed to provide more reliable toxicological data. Moreover, mixture-induced corneal damage correlated with increased ROS levels, suggesting a close correlation between tissue death and oxidative stress. Besides mixtures showing the potential to induce moderate/mild ocular toxicity, we could verify that the corneal tissue damage showed reversibility due to the recovery from the injury after exposure to some of the mixtures. Hence, our ex vivo corneal model seems to be a simple and cost-effective approach for future studies related to further investigating the reversibility of damage in the cornea triggered by chemicals and their mixtures.

Alphabet Soup: Clinical Pearls for the Retina Specialist-Ocular Toxicity of Advanced Antineoplastic Agents in Systemic Cancer Care.

Targeted antineoplastic agents and immunotherapies have revolutionized management strategies available for previously refractory cancer. Despite the growing list of pharmacologic agents and indications, many of the currently Food and Drug Administration-approved therapies are associated with ocular adverse effects. Retina specialists and oncologists should be aware of potential side effects because some may be severe and permanent. Although most ocular side effects require conservative treatment without discontinuation of life-preserving therapies, rare severe adverse reactions can be potentially blinding and may warrant an extensive discussion regarding different management strategies, including cessation of life-preserving therapy.

Strategy Combining Nonanimal Methods for Ocular Toxicity Evaluation.

Historically, the ocular toxicity of manufactured consumer materials has been evaluated using the rabbit in vivo Draize rabbit eye test. The animal data obtained were used by the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (UN GHS) to define the classification and labelling (C&L) for eye damage/irritation endpoint. However, the Draize test, a method which was never formally validated, has been widely criticized because of its technical limitations. In addition, ethical and economic issues and advances in scientific knowledge, and political and public pressures have made animal experimentation unsustainable. This scenario has consequently led to the development of nonanimal testing and protocols/approaches with considerable predictive value and relevance for humans. It is widely accepted that one single nonanimal method cannot cover all the criteria of damage/inflammation assessed by regulatory adopted in vivo animal testing. Thus, integrated testing strategies (ITS) have been proposed, including a tiered testing approach combining different nonanimal testing with different endpoints, which have been used for regulatory purposes, on a case-by-case basis and within integrated approaches to testing and assessment (IATA), to identify materials according to their ability to trigger eye damage. In particular, the top-down and bottom-up approaches have been recommended for the C&L of materials, which cause serious eye damage or eye irritation, respectively. This chapter describes detailed protocols for eye irritation testing based on cells (Short Time Exposure-STE, OECD No. 491/2017), a vascularized membrane (the Hen's Egg Test-Chorioallantoic Membrane-HET-CAM) and corneal tissue (Bovine Corneal Opacity and Permeability-BCOP, OECD No. 437/2017), which can be applied using top-down or bottom-up approaches. In addition, it suggests making a corneal histomorphometric evaluation as an additional parameter in the BCOP method to differentiate materials that cause serious eye tissue damage (UN GHS Cat. 1) from materials that have reversible eye irritation effects (UN GHS Cat. 2).

About a case of blindness following scorpion envenomation

The author reports a case of blindness occurred after three scorpion stings in a young woman from the region Ouargla, Algeria. The absence of signs of neurological and cardiovascular envenomation and the functional examinations of eyes is likely to be the consequence of a toxic neuropathy. Two months later, blindness persists and functional prognosis remains reserved.(AU)

Epidemiological Bulletin, v. 14, n.2, Jun. 1993

IN THIS ISSUE: Epidemic neuropathy in Cuba | Methodology for the study of inequalities in the health situation | Health Statistics from the Americas | Tracing infection by T. Cruzi in El Salvador | Caribbean Epidemiology Center AdvisoryCommittee | Calendar of Meetings | International Classification of Diseases | AIDS Surveillance in the Americas | Evaluation of epidemiology course in Haiti

Boletín Epidemiológico, v. 14, n. 2, Jun. 1993 

EN ESTE NÚMERO: Neuropatía epidémica en Cuba | Metodología para el estudio de desigualdades en la situación de salud | Estadísticas de salud de las Américas | Rastreo de infección por T. Cruzi en El Salvador | Calendario de reuniones | Comité Científico del Cento de Epidemiología del Caribe | Clasificación Internacional de Enfermedades | Vigilancia del SIDA en las Américas | Evaluación de curso de epidemiología en Haití