MLtox, online phototoxicity prediction webpage

Phototoxicity, sometimes in the literature referred to as photo-irritation, is a chemically induced reaction requiring light. While it is generally accepted that phototoxicity testing can be performed in the majority of cases in vitro (i.e. without the use of experimental animals), these tests may sometimes provide contradictory predictions. Understanding the mechanisms of initiating events based on the molecule's structure and its ability to reach the excited state and consequently generate ROS enables the creation of predictive QSAR for this adverse outcome. The ability to predict the phototoxicity potential via a QSAR model is beneficial in reducing the number of mechanical in vitro/in chemico tests needed to demonstrate absence of phototoxicity and it is very helpful in the overall safety assessment process. The QSAR prediction model presented here focused on developing a robust platform freely available on the web via the link http://mltox.online to provide interpretable predictions of the phototoxicity of tested molecules. Great attention was devoted to interpretability and explainability of the prediction results. The web application allows the user to input a chemical by CAS number, SMILES code or trivial name. The user can choose between simple prediction or advanced tools options. These extended tools include the artificial intelligence explainability of model prediction using XSMILES (interactive visualization technique to support the interpretation of SMILES) and SHAP values (impact each element on the prediction). The comprehensive tools in question allow the user to explore the properties of phototoxic substances and to understand the prediction outcomes better.

The "Big Three" in biocompatibility testing of medical devices: implementation of alternatives to animal experimentation-are we there yet?

Biocompatibility testing ensures the safety of medical devices by assessing their compatibility with biological systems and their potential to cause harm or adverse reactions. Thus, it is a critical part of the overall safety evaluation process for medical devices. Three primary types of biocompatibility tests-cytotoxicity, irritation, and sensitisation assessment-are standard for nearly all medical devices. However, additional biocompatibility tests, such as genotoxicity, systemic toxicity, hemocompatibility, and implantation studies, may also be necessary, depending on the device's nature and intended use. The testing is partly conducted in vitro, but the industry still heavily relies on animal experiments. Compared to other industrial sectors, implementing alternatives in medical device biocompatibility testing has been notably slower. This delay can be attributed to the absence of specific validation processes tailored to medical devices and the resulting hesitation regarding the predictive capacity of these alternative methods despite their successful applications in other domains. This review focuses on the progress and obstacles to implementing new approach methodologies in the areas of cytotoxicity, irritation and sensitisation testing of medical devices. While challenges persist in adopting these innovative methods, the trend towards embracing alternatives remains robust. This trend is driven by technological advancements, ethical considerations, and growing industrial interest and support, all collectively contributing to advancing safer and more effective medical devices.

The Safety Assessment of Cosmetic Perfumes by Using In Chemico and In Vitro Methods in Combination with GC-MS/MS Analysis

Animal testing has been prohibited for the safety assessment of cosmetic ingredients or finished products. Thus, alternative non-animal methods, followed by confirmatory clinical studies on human volunteers, should be used as the sole legally acceptable approach within the EU. The safety assessment of cosmetic products requires the involvement of multiple scientific disciplines, including analytical chemistry and biomedicine, as well as in chemico, in vitro and in silico toxicology. Recent data suggest that fragrance components may exert multiple adverse biological effects, e.g. cytotoxicity, skin sensitisation, (photo)genotoxicity, mutagenicity, reprotoxicity and endocrine disruption. Therefore, a pilot study was conducted with selected samples of fragrance-based products, such as deodorant, eau de toilette and eau de parfum, with the aim of integrating results from a number of alternative non-animal methods suitable for the detection of the following toxicological endpoints: cytotoxicity (with 3T3 Balb/c fibroblasts); skin sensitisation potential (in chemico method, DPRA); skin sensitisation potential (LuSens in vitro method, based on human keratinocytes); genotoxicity potential (in vitro Comet assay with 3T3 Balb/c cells); and endocrine disruption (in vitro YES/YAS assay). The presence of twenty-four specific known allergens in the products was determined by using GC-MS/MS. The strategies for estimation of the NOAEL of a mixture of allergens, which were proposed by the Scientific Committee on Consumer Products in their 'Opinion on Tea tree oil' document and by the Norwegian Food Safety Authority in their 'Risk Profile of Tea tree oil' report, were used as models for the NOAEL estimation of the mixtures of allergens that were identified in the individual samples tested in this study.