Skin Sensitization Potential Research Articles

Assessment of the feed additive consisting of Lentilactobacillus buchneri (formerly Lactobacillus buchneri) DSM 22501 for all animal species for the renewal of its authorisation (Chr. Hansen A/S).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application for renewal of the authorisation of the additive consisting of Lentilactobacillus buchneri DSM 22501 as a technological feed additive to improve ensiling of fresh material for all animal species. The applicant has provided evidence that the additive currently on the market complies with the existing conditions of authorisation. There is no new evidence that would lead the FEEDAP Panel to reconsider its previous conclusions. Thus, the Panel concludes that the additive remains safe for all animal species, consumer and the environment under the authorised conditions of use. Regarding user safety, the additive is not irritant to skin and eye, but owing to its proteinaceous nature it should be considered a respiratory sensitiser. No conclusions could be drawn on the skin sensitisation potential of the additive. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Utilizing integrated testing strategy (ITSv1) defined approach and read across to predict skin sensitization of cannabidiol

Cannabidiol (CBD) is increasingly being used as an ingredient in cosmetics, but to date no pre-clinical studies have been published to address the skin sensitization end point. This case study investigated its skin sensitization potential for use in a face cream application at 0.3 % using Next Generation Risk Assessment (NGRA) framework. Based on chemical structure and in-silico prediction using Derek Nexus, CBD was predicted to be weak sensitizer with a resorcinol alert moiety. In vitro testing was conducted confirming it to be sensitizer, but the New Approach Methodologies (NAM) data could not provide sufficient confidence to determine a point of departure (PoD). Integrated testing strategy (ITS)v1 Defined Approach (DA), adopted in OECD Guideline No. 497, was used for skin sensitization potency categorization. However, ITSv1 DA alone is not used for further refinement of the potency prediction based on EC3 (the estimated concentration that produces a stimulation index of 3 in murine local lymph node assay) values. Therefore, the application of read-across using Derek Nexus derived a PoD derived from the LLNA EC3 of 42 %. This led to a favorable NGRA conclusion and to support use of CBD at 0.3 % in face cream application.

A botanical reference set illustrating a weight of evidence approach for skin sensitization risk assessment

Recent years have seen an increase in the use of botanicals and natural substances (BNS) in consumer products such as cosmetics and household care products. Most work conducted to date to assess botanicals for human safety has focused their use as dietary supplements and thus on systemic toxicity. However, the induction of skin sensitization is a possible adverse effect of natural products in particular those that come into skin contact, especially for cosmetics that remain on the skin and are not rinsed off following use. Assessments of BNS ingredients are often challenging for a number of reasons: the BNS are complex mixtures that can be of mostly unknown composition; the composition can be highly variable even within the same plant species and dependent on how processed; the physical form of the BNS raw material can vary from a highly concentrated powdered extract to a liquid extract containing only a small percentage of the BNS; testing of the BNS raw materials in New Approach Methods (NAM) has uncertainty as these methods are often not developed or validated for complex mixtures. In this study, a reference set of 14 selected BNS which span the range of skin sensitization potential was complied. These data were used in a Weight of Evidence (WoE) approach to evaluate their skin sensitization potential with each of the data rich BNS being classified as either having strong evidence of inducing skin sensitization based on human topical use history, animal data, clinical data, composition data and NAM data, or having some but more limited (weak) evidence of inducing skin sensitization, or having strong evidence of no skin sensitization potential. When available data have sufficient potency related information, sensitization potency assessment is also provided based on WoE, classifying these BNS as either strong, moderate, or weak sensitizers, or non-sensitizers. An outline for a BNS skin sensitization risk assessment framework is proposed starting with exposure-based waiving and WoE assessment for higher exposures. In addition to demonstrating the application of the WoE approach, the reference set presented here provides a set of ‘data rich’ botanicals which cover a range of sensitization potencies that could be used for evaluating existing test methods or aid in the development of new predictive models for skin sensitization.

Safety and efficacy of a feed additive consisting of Pediococcus acidilacticiCNCM I-4622 for all insect species (Danstar Ferment AG).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Pediococcus acidilactici CNCM I-4622 as a zootechnical additive (functional group: physiological condition stabilisers) for all insects. The active agent used in the additive is already authorised for use in all animal species as a technological additive, and as a zootechnical additive in all Suidae species for fattening and for breeding, other than sows, all avian species, all fish species and all crustaceans. The active agent has been identified as a strain of P. acidilactici and consequently meets the qualifications required by the qualified presumption of safety (QPS) approach. The use of the additive is considered safe for all insect species, consumers and the environment. The additive is considered non-irritant to skin and eyes but a respiratory sensitiser. No conclusions can be drawn regarding its skin sensitisation potential. In the absence of adequate data, the FEEDAP Panel is not in the position to conclude on the efficacy of the additive as a physiological condition stabiliser for honeybees nor for all insect species.

Assessment of the feed additive consisting of Lentilactobacillus buchneri (formerly Lactobacillus buchneri) NCIMB 30139 for all animal species for the renewal of its authorisation (Volac International Ltd).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application for renewal of Lentilactobacillus buchneri (formerly Lactobacillus buchneri) NCIMB 30139 as a technological additive for use in easy to ensile fresh material for all animal species. The applicant has provided evidence that the additive currently on the market complies with the existing conditions of authorisation. There is no new evidence that would lead the FEEDAP Panel to reconsider its previous conclusions. Thus, the Panel concludes that the additive remains safe for all animal species, consumer and the environment under the authorised conditions of use. Regarding user safety, the additive should be considered as a respiratory sensitiser. The additive is not skin irritant, but no conclusions can be drawn on the skin sensitisation or eye irritation potential of the additive. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Assessment of the feed additive consisting of Enterococcus faeciumDSM 21913, Bifidobacterium animalisDSM 16284 and Ligilactobacillus salivariusDSM 16351 (Biomin® C3) for chickens for fattening, chickens reared for laying and minor poultry species other than laying for the renewal of its authorisation and extension of use in all poultry species for fattening and reared for laying/breeding (Biomin GmbH).

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of the feed additive containing Enterococcus faecium DSM 21913, Bifidobacterium animalis ssp. animalis DSM 16284 and Ligilactobacillus salivarius (formerly Lactobacillus salivarius) DSM 16351 (Biomin® C3) as a zootechnical feed additive (functional group: gut flora stabiliser) in the context of the renewal of the authorisation for chickens for fattening, chickens reared for laying and minor poultry species other than laying. In addition, the applicant requested the extension of use in all poultry species for fattening and reared for laying/breeding. The applicant provided evidence that the additive currently in the market complies with the conditions of the authorisation. There is no new evidence that would lead the Panel to reconsider previous conclusions that the additive is safe for the target species, consumers and the environment under the authorised conditions of use. This conclusion also applies to the target species for which a request for an extension of use is made. The Panel concluded that Biomin® C3 is not irritant to skin or eyes but should be considered as a respiratory sensitiser due to its proteinaceous nature. No conclusions could be drawn on the skin sensitisation potential of the additive. The evaluation of the efficacy is not needed in those species for which an authorisation exists. The Panel considered that the additive is efficacious in all growing poultry species at the same inclusion level of 1 × 108 CFU/kg feed and the equivalent level in water of 5 × 107 CFU/L.

Assessment of the feed additive consisting of Levilactobacillus brevisDSM 23231 for all animal species for the renewal of its authorisation (Biomin GmbH).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Levilactobacillus brevis (formerly Lactobacillus brevis) DSM 23231 as a technological feed additive for all animal species. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that evidence has been provided that the additive currently on the market complies with the existing terms of authorisation. The Panel also concluded that L. brevis DSM 23231 remains safe for all animal species, consumers and the environment under the authorised conditions of use. The additive should be considered a respiratory sensitiser. Based on the studies submitted regarding user safety, the preparation of the additive tested was shown not to be a skin or eye irritant. The Panel was not in the position to conclude on the skin sensitisation potential of the additive. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Application of an Antioxidant Response Element-Nuclear Factor Erythroid 2 Luciferase Assay for Assessing the Skin Sensitization Potential of Agrochemicals.

The skin sensitization potential of agrochemicals can be assessed using laboratory methods such as the keratinocyte activation assay so that their use in regulatory toxicology might replace experimental animal testing. Here, we evaluated the skin sensitization potential of 11 agrochemicals by using an antioxidant response element-nuclear factor erythroid 2 luciferase assay in KeratinoSens and LuSens cells and applying a skin sensitization adverse outcome pathway (AOP). The KeratinoSens and LuSens assays consistently evaluated the skin sensitization potential of 10/11 agrochemicals with reference to animal testing databases. Benomyl, pretilachlor, fluazinam, terbufos, butachlor, and carbosulfan were correctly detected as sensitizers, and glufosinate ammonium, oxiadiazon, tebuconazole, and etofenprox were correctly detected as non-sensitizers. For diazinon, the skin sensitizing potential was positive in the KeratinoSens assay but not in the LuSens assay. These results suggest that the evaluation of in vitro skin sensitization using the AOP mechanism can be applied to assess active agrochemicals.

Safety and efficacy of a feed additive consisting of Weizmannia faecalisDSM 32016 (TechnoSpore50®) for poultry for fattening, poultry reared for laying/breeding, ornamental birds and suckling and weaned Suidae piglets (Biochem Zusatzstoffe Handels- und Produktionsgesellschaft GmbH).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Weizmannia faecalis (formerly identified as Bacillus coagulans) DSM 32016 (TechnoSpore50®) as a zootechnical feed additive for poultry reared for breeding/laying/fattening, ornamental birds and suckling and weaned Suidae piglets. The additive is authorised for use in feed for poultry for fattening, ornamental birds and suckling and weaned Suidae piglets. This application sought the extension of use in feed for poultry reared for breeding/laying and the new authorisation in water for drinking for suckling and weaned Suidae piglets, poultry for fattening, reared for breeding/laying and ornamental birds. Moreover, the applicant requested the authorisation of simultaneous use in feed for poultry reared for breeding and laying with coccidiostats. The identity and the lack of toxigenic activity of the active agent was confirmed, and it did not show resistance to relevant antibiotics; therefore, the strain was presumed safe for the target species, consumers and the environment. Since other components did not introduce concerns, TechnoSpore50® was also considered safe for the target species, consumers and the environment. The additive is not a skin/eye irritant but is a respiratory sensitiser. No conclusions could be drawn on the skin sensitisation potential of the additive. TechnoSpore50® was considered to be efficacious in feed for poultry reared for laying/breeding at 1 × 109 CFU/kg and in water for drinking for poultry reared for fattening, poultry reared for laying/breeding, ornamental birds and for suckling and weaned Suidae piglets at5 × 108 CFU/L. TechnoSpore50® is compatible with halofuginone, diclazuril, monensin sodium, robenidine hydrochloride, salinomycin sodium and monensin sodium + nicarbazin, but not with narasin or narasin + nicarbazin. No conclusions could be drawn on the compatibility of TechnoSpore50® with decoquinate, lasalocid A sodium, semduramicin sodium, nicarbazin or amprolium hydrochloride.

The inter-laboratory validation study of EpiSensA for predicting skin sensitization potential.

The Epidermal Sensitization Assay (EpiSensA) is a reconstructed human epidermis (RhE)-based gene expression assay for predicting the skin sensitization potential of chemicals. Since the RhE model is covered by a stratified stratum corneum, various kinds of test chemicals, including lipophilic ones and pre-/pro-haptens, can be tested with a route of exposure akin to an in vivo assay and human exposure. This article presents the results of a formally managed validation study of the EpiSensA that was carried out by three participating laboratories. The purpose of this validation study was to assess transferability of the EpiSensA to new laboratories along with its within- (WLR) and between-laboratory reproducibility (BLR). The validation study was organized into two independent stages. As demonstrated during the first stage, where three sensitizers and one non-sensitizer were correctly predicted by all participating laboratories, the EpiSensA was successfully transferred to all three participating laboratories. For Phase I of the second stage, each participating laboratory performed three experiments with an identical set of 15 coded test chemicals resulting in WLR of 93.3%, 93.3%, and 86.7%, respectively. Furthermore, when the results from the 15 test chemicals were combined with those of the additional 12 chemicals tested in Phase II of the second stage, the BLR for 27 test chemicals was 88.9%. Moreover, the predictive capacity among the three laboratories showed 92.6% sensitivity, 63.0% specificity, 82.7% accuracy, and 77.8% balanced accuracy based on murine local lymph node assay (LLNA) results. Overall, this validation study concluded that EpiSensA is easily transferable and sufficiently robust for assessing the skin sensitization potential of chemicals.

Reconstructed human epidermis-based testing strategy of skin sensitization potential and potency classification using epidermal sensitization assay and in silico data.

The hazards and potency of skin sensitizers are traditionally determined using animal tests such as the local lymph node assay (LLNA); however, significant progress has been made in the development of non-animal test methods addressing the first three mechanistic key events of adverse outcome pathway in skin sensitization. We developed the epidermal sensitization assay (EpiSensA), which is a reconstructed human epidermis-based assay, by measuring four genes related to critical keratinocyte responses during skin sensitization. Four in vitro skin sensitization test methods (EpiSensA, direct peptide reactivity assay [DPRA], KeratinoSens™, and human cell line activation test [h-CLAT]) were systematically evaluated using 136 chemicals including lipophilic chemicals and pre/pro-haptens, which may be related to assay-specific limitations. The constructed database included existing and newly generated data. The EpiSensA showed a broader applicability domain and predicted the hazards with 82.4% and 78.8% accuracy than LLNA and human data. The EpiSensA could detect 76 out of 88 sensitizers at lower concentrations than the LLNA, indicating that the EpiSensA has higher sensitivity for the detection of minor sensitizing constituents. These results confirmed the potential use of the EpiSensA in evaluating a mixture of unknown compositions that can be evaluated by animal tests. To combine different information sources, the reconstructed human epidermis-based testing strategy (RTS) was developed based on weighted multiple information from the EpiSensA and TImes MEtabolism Simulator platform for predicting Skin Sensitization (TIMES-SS; RTSv1) or Organization for Economic Cooperation and Development (OECD) QSAR Toolbox automated workflow (RTSv2). The predictivities of the hazards and Globally Harmonized System (GHS) subcategories were equal to or better than the defined approaches (2 out of 3, integrated testing strategy [ITS]v1, and ITSv2) adopted as OECD Guideline 497.

Assessment of the feed additive consisting of Enterococcus lactisDSM 7134 and Lacticaseibacillus rhamnosusDSM 7133 (Provita LE) for calves for rearing for the renewal of its authorisation (Lactosan GmbH & Co.KG).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application for renewal of the authorisation of the additive Provita LE for calves for rearing, consisting of Enterococcus lactis DSM 7134 (formerly identified as Enterococcus faecium) and Lacticaseibacillus rhamnosus DSM 7133 (formerly identified as Lactobacillus rhamnosus) as a zootechnical feed additive. The applicant has provided evidence that the additive currently on the market complies with the existing terms of the authorisation. The FEEDAP Panel concluded that the use of the feed additive in animal nutrition remains safe for calves for rearing, consumers and the environment under the authorised conditions of use. The additive is not irritant to skin or eyes but should be considered a respiratory sensitiser. It was not possible to draw conclusions on the skin sensitisation potential of the additive under assessment. There was no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Assessment of a feed additive consisting of Lentilactobacillus buchneriDSM 19455 for all animal species for the renewal of its authorisation (Biomin GmbH).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Lentilactobacillus buchneri DSM 19455 as a technological feed additive for use in easy and moderately difficult to ensile fresh material for all animal species. The Panel concluded that L. buchneri DSM 19455 remains safe for all animal species, consumers and the environment under the authorised conditions of use. Regarding user safety, L. buchneri DSM 19455 was considered to be a respiratory sensitiser. The additive with inulin as a carrier tested is not irritant to skin and eyes. The Panel was not in the position to conclude on the skin sensitisation potential of the additive. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Safety and efficacy of the feed additive consisting of Enterococcus lactisNCIMB 10415 (Cylactin®) for all poultry for fattening or reared for laying/breeding and ornamental birds, all Suidae, calves and other ruminant species for fattening or rearing (DSM Nutritional products Ltd).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of Cylactin® as zootechnical additive. The active agent of the additive is Enterococcus lactis NCIMB 10415, and three additive formulations currently authorised: Cylactin® LBC G35, Cylactin® LBC ME10 and Cylactin® LBC ME20 plus. The additive is currently authorised in the EU for use in poultry (chickens and minor poultry species for fattening, chickens and minor species reared forlaying), calves and kids for rearing and for fattening, sows, suckling and weaned piglets and pigsfor fattening. The applicant is now seeking the renewal of its authorisation and the extension of use for chickens and minor poultry species reared for breeding, turkeys for fattening and reared for breeding, ornamental birds, lambs for rearing and for fattening, minor or other ruminants' species forrearing and fattening, minor suckling and weaned Suidae species, pigs and minor Suidae species for fattening, rearing or reproduction. In addition, the applicant is seeking authorisation for use in water for drinking for all above-mentioned target species and categories. The applicant has provided evidence that the additive currently on the market complies with the conditions of authorisation. The FEEDAP Panel concludes that the additive is safe for the target animals, consumers and the environment under the authorised/new proposed conditions of use. The Cylactin® LBC ME10 and LBC ME20 plus are not skin and eye irritants, but no conclusion could be drawn on the potential of Cylactin® LBC G35 to be skin and eye irritant. Moreover, no conclusions could be drawn on theadditive skin sensitisation potential. The additive is considered a potential respiratory sensitiser. The efficacy for the new target species/categories as well its use in water was extrapolated from the previous efficacy studies.

Assessment of the feed additive consisting of Enterococcus lactisDSM 7134 (Bonvital®) for chickens reared for laying and minor poultry species other than those used for laying for the renewal of its authorisation (Lactosan GmbH & Co.KG).

Bonvital® is the trade name for a feed additive currently authorised for use in piglets, pigs for fattening, sows, chickens for fattening, laying hens, chickens reared for laying and minor poultry species (other than those used for laying). This opinion concerns the renewal of the authorisation of Bonvital® as a zootechnical additive for chickens reared for laying and minor poultry species other than those used for laying. The active agent of Bonvital® was originally identified as Enterococcus faecium. During the current assessment, the strain was reassigned to Enterococcus lactis. The applicant provided evidence that the additive currently on the market complies with the existing terms of authorisation. There is no new evidence that would lead the FEEDAP Panel to reconsider its previous conclusions. Thus, the Panel concluded that the additive remains safe for the target species, consumers and the environment under the authorised conditions of use. Bonvital® was found to be non-irritant to skin and eyes, but a potential respiratory sensitiser. No conclusions could be drawn on the skin sensitisation potential of the additive. There is no need to assess the efficacy of Bonvital® in the context of the renewal of the authorisation.

Sensitization Assessment of Extractables and Leachables in Pharmaceuticals: ELSIE Database Analysis.

Quality by design is the foundation of the risk management framework for extractables and leachables (E&Ls) recommended by the Extractables and Leachables Safety Information Exchange (ELSIE). Following these principles during the selection of materials for pharmaceutical product development minimizes the presence of highly toxic substances and decreases the health risk of potential leachables in the drug product. Therefore, in the context of the broad arena of chemicals, it is important to distinguish E&Ls as a subset of chemicals and evaluate this relevant chemical space to derive appropriate analytical and safety thresholds. When considering the health hazards posed by E&Ls, one area presenting a challenge is understanding the sensitization potential and whether it poses a risk to patients. A dataset of E&Ls compiled by ELSIE (n = 466) was analyzed to determine the prevalence and potency of skin sensitizers in this chemical subset and explore a scientifically justified approach to the sensitization assessment of potential leachables in parenteral drug products. Approximately half of the compounds (56%, 259/466) had sensitization data recorded in the ELSIE database and of these, 20% (52/259) are potential skin sensitizers. Only 3% (8/259) of the E&L dataset with sensitization data were considered potent (strong or extreme) sensitizers following in silico analysis and expert review, illustrating that potent sensitizers are not routinely observed as leachables in pharmaceutical products. Our analysis highlights that in silico potency prediction and expert review are key tools during the sensitization assessment process for E&Ls. The results confirm where material selection is anticipated to mitigate the risk of presence of strong and/or extreme sensitizers (e.g., extractable testing via ISO 10993-10), and that implementing thresholds per ICH M7 and/or Masuda-Herrera et al. provides a reasonably conservative approach for establishing the analytical testing and safety thresholds.

A Randomized Double-blind Study to Assess the Skin Irritation and Sensitization Potential of a Once-weekly Donepezil Transdermal Delivery System in Healthy Volunteers.

A once-weekly donepezil transdermal delivery system (TDS; Adlarity; Corium, LLC) is indicated for the treatment of mild, moderate, and severe dementia of the Alzheimer type. In this placebo-controlled, randomized, double-blind phase 1 trial, healthy volunteers aged 40 years or older were randomized to receive a placebo and donepezil TDS and were evaluated for the primary endpoints of skin irritation and sensitization potential. Skin irritation was scored. Two hundred fifty-six participants were randomized and received ≥1 dose of any treatment. After the first weekly TDS application, no skin irritation or minimal irritation was evident between donepezil and placebo TDSs. At the third weekly TDS application, for donepezil TDS, the average of the mean combined skin irritation score was 0.55 of a possible maximum of 7, indicating none to minimal skin irritation, and for placebo, the score was 0.19, indicating no skin irritation. Of 198 participants, 4 (2.0%) were considered potentially sensitized to donepezil TDS, and 0 were potentially sensitized to placebo TDS. Once-weekly 5-mg/d donepezil TDS demonstrated minimal skin irritation under conditions of use of 3 consecutive weekly patch applications to the same skin site and minimal sensitization potential.

P22-20: Skin sensitization potency prediction based on read-across with reliably selected analogue and RhE based Testing Strategy (RTS)

P22-20: Skin sensitization potency prediction based on read-across with reliably selected analogue and RhE based Testing Strategy (RTS)

P17-34: Adoption of the OECD TG 442D for the in vitro assessment of skin sensitization potential of graphene-related materials

P17-34: Adoption of the OECD TG 442D for the in vitro assessment of skin sensitization potential of graphene-related materials

P22-41: An innovative modular in silico model to predict skin sensitisation potential

P22-41: An innovative modular in silico model to predict skin sensitisation potential