In silico assessment of developmental and reproductive toxicity
Chemicals leaching from medical devices are toxicologically not always fully characterized. Supplementary approaches are therefore needed to allow for a detailed hazard assessment. In this article the use of in silico toxicology to identify and quantify the developmental and reproductive toxicity (DART) potential of substances is investigated. Reproductive toxicity represents the harmful effects of chemical exposure on […]
Genotoxicity assessment of medical devices
If chemical analytical testing and the toxicological risk assessment fails to demonstrate that leachables of a medical device are associated with an acceptable risk for genotoxicity, genotoxicity tests are required to assess the potential presence of toxins that can impact the genetic material of cells. Since no single test can detect all genotoxins, the standard for medical device genotoxicity testing […]
In vitro assessment of respiratory toxicity: selection of a suitable cell line
With the human lung having more than 60 different cell types and a variety of different cell functions present, the in vitro assessment of respiratory toxicity is a challenging endeavor. Each cell type and the function it performs represents a potential target for a toxic mechanism of action. The first question when selecting a suitable […]
Intra- and Inter-assay variability of cytotoxicity testing
The viability of cells in cytotoxicity assays is always calculated relative to untreated control cells that undergo the same seeding and exposure procedure but receive only crude extraction media that has been incubated without the test item. Moreover, the spectrometric signal measured for a specific well in the assay is always corrected by blanks in the assay […]
In vitro alternatives for skin sensitization testing of medical devices
Besides cytotoxicity and irritation, sensitization is one of the three biological endpoints that must be evaluated for all medical devices independent of type and duration of their body contact (ISO 10993-1). In contrast to irritation (ISO 10993-23) and cytotoxicity (ISO 10993-5), validated in vitro methods that are qualified and well established in routine use are still lacking […]
Intralaboratory comparability of cytotoxicity testing conducted according to ISO 10993-5
In vitro cytotoxicity testing is an essential part of the biocompatibility assessment of new materials. However, the ISO 10993-5 standard allows a high degree of variability in the choice of test conditions between individual tests. It is therefore not always possible to directly compare test results between tests without taking the actual test conditions into account. In […]
Interlaboratory comparability of cytotoxicity testing conducted according to ISO 10993-5
The ISO standard for the performance of cytotoxicity assays for medical devices does not explicitly specify the type of cytotoxicity assay to be used and also allows a high degree of freedom in the choice of exact test parameters. This may lead to significant differences in test results among laboratories and depending on the type […]
Probabilistic derivation of population thresholds for human skin sensitizer
Reynolds et al. has introduced the concept of a population threshold for human skin sensitizers – a chemical-specific exposure level at which no individual in a population will experience induction of contact allergy to a chemical. Therefore, a Bayesian multilevel (hierarchical) regression model was developed to estimate population thresholds under the conditions of a human-repeat-insult-patch-test. […]
QMS: Entanglement of biological safety and hazardous substance assessments
The compliance of medical devices with hazardous substance regulations and ensuring their biological safety are entangled tasks. At Medical Matters, biological safety and hazardous substance assessments are therefore strongly interlinked. If the portfolio of a medical devices manufacturer includes an article with an identified hazardous substance above the 0.1% (w/w) MDR limit, regulatory obligations get […]
Quantitative acceptance criteria for chemical equivalency testing
Chemical equivalency testing can be used to assess the biocompatibility impact of changes on final finished devices. However, one drawback of this approach is the lack of acceptance criteria for determining if two sets of extractables data are effectively equivalent. To address this gap David M. Saylor and Joshua A. Young have published an article in Journal […]