Integrated in silico strategy for PBT assessment and prioritization under REACH.

Chemicals may persist in the environment, bioaccumulate and be toxic for humans and wildlife, posing great concern. These three properties, persistence (P), bioaccumulation (B), and toxicity (T) are the key targets of the PBT-hazard assessment. The European regulation for the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) requires assessment of PBT-properties for all chemicals that are produced or imported in Europe in amounts exceeding 10 tonnes per year, checking whether the criteria set out in REACH Annex XIII are met, so the substance should therefore be considered to have properties of very high concern. Considering how many substances can fall under the REACH regulation, there is a pressing need for new strategies to identify and screen large numbers fast and inexpensively. An efficient non-testing screening approach to identify PBT candidates is necessary, as a valuable alternative to money- and time-consuming laboratory tests and a good start for prioritization since few tools exist (e.g. the PBT profiler developed by US EPA). The aim of this work was to offer a conceptual scheme for identifying and prioritizing chemicals for further assessment and if appropriate further testing, based on their PBT-potential, using a non-testing screening approach. We integrated in silico models (using existing and developing new ones) in a final algorithm for screening and ranking PBT-potential, which uses experimental and predicted values as well as associated uncertainties. The Multi-Criteria Decision-Making (MCDM) theory was used to integrate the different values. Then we compiled a new set of data containing known PBT and non-PBT substances, in order to check how well our approach clearly differentiated compounds labeled as PBT from those labeled as non-PBT. This indicated that the integrated model distinguished between PBT from non-PBT compounds.

Comparison between bioconcentration factor (BCF) data provided by industry to the European Chemicals Agency (ECHA) and data derived from QSAR models.

The bioconcentration factor (BCF) is the ratio of the concentration of a chemical in an organism to the concentration in the surrounding environment at steady state. It is a valuable indicator of the bioaccumulation potential of a substance. BCF is an essential environmental property required for regulatory purposes within the Registration, Evaluation, Authorization and restriction of Chemicals (REACH) and Globally Harmonized System (GHS) regulations. In silico models for predicting BCF can facilitate the risk assessment for aquatic toxicology and reduce the cost and number of animals used. The aim of the present study was to examine the correlation of BCF data derived from the dossiers of registered chemicals submitted to the European Chemical Agency (ECHA) with the results of a battery of Quantitative Structure-Activity Relationship (QSAR). After data pruning, statistical analysis was performed using the predictions of the selected models. Results in terms of R(2) had low rating around 0.5 for the pruned dataset. The use of the model applicability domain index (ADI) led to an improvement of the performance for compounds falling within it. The variability of the experimental data and the use of different parameters to define the applicability domain can influence the performance of each model. All available information should be adapted to the requirements of the regulation to obtain a safe decision.

CORAL: model for no observed adverse effect level (NOAEL).

The in vivo repeated dose toxicity (RDT) test is intended to provide information on the possible risk caused by repeated exposure to a substance over a limited period of time. The measure of the RDT is the no observed adverse effect level (NOAEL) that is the dose at which no effects are observed, i.e., this endpoint indicates the safety level for a substance. The need to replace in vivo tests, as required by some European Regulations (registration, evaluation authorization and restriction of chemicals) is leading to the searching for reliable alternative methods such as quantitative structure-activity relationships (QSAR). Considering the complexity of the RDT endpoint, for which data quality is limited and depends anyway on the study design, the development of QSAR for this endpoint is an attractive task. Starting from a dataset of 140 organic compounds with NOAEL values related to oral short term toxicity in rats, we developed a QSAR model based on optimal descriptors calculated with simplified molecular input-line entry systems and the graph of atomic orbitals by the Monte Carlo method, using CORAL software. Three different splits into the training, calibration, and validation sets are studied. The mechanistic interpretation of these models in terms of molecular fragment with positive or negative contributions to the endpoint is discussed. The probabilistic definition for the domain of applicability is suggested.

Direct effects of the algal toxin, domoic acid, on ovarian function: Bovine granulosa and theca cells as an in vitro model.

Domoic acid (DA) is a potent neurotoxin produced by alga Pseudo-nitzschia spp. and has been associated with reproductive disorders in mammals. The aim of this study was to investigate if DA can affect the reproductive system via direct action on ovarian function. Bovine granulosa and theca cells were used as in vitro models for evaluating DA effects on ovarian cell proliferation and steroid production. In small-follicle granulosa cells (SMGC), cell proliferation and estradiol (E2) production was not affected (P>0.05) while progesterone (P4) production was inhibited (P<0.05) by DA at all doses tested. In large-follicle granulosa cells (LGGC), DA had no effect (P>0.05) on cell proliferation or P4 production while E2 production was stimulated by 1 and 5 µg/ml DA (P<0.05). DA (1 µg/ml) attenuated (P<0.05) insulin-like growth factor 1 (IGF-1)-induced P4 production by large-follicle theca cells (LGTC), but did not affect androstenedione (A4) production or proliferation of LGTC. In glutamate-free medium, DA inhibited (P<0.05) SMGC E2 production and this inhibition was similar to inhibition of E2 by trans-(±)-1-amino-1,3-cyclopentanedicarboxylic acid monohydrate (ACPD; a selective metabotropic glutamate receptor subtype agonist) while kainic acid (KA; an ionotropic glutamate receptor subtype agonist) had no effect (P>0.10) on E2 production. Collectively, these results show for the first time that DA has direct effects on ovarian GC and TC steroidogenesis. Because DA inhibited E2 and P4 production, DA has the potential to be an endocrine disruptor.

Student perspectives on the use of alternative methods for teaching in veterinary faculties.

The use of alternative methods for teaching purposes is gradually increasing in higher education. In order to evaluate the usefulness of non-animal based practical classes in veterinary science, and to inform on possible benefits and limitations of these teaching tools, a questionnaire was designed and distributed to students. Although there was no complete agreement among the student responses, it was apparent that the majority of the students would like traditional training methods to be paired with alternative approaches, and expressed their desire to be exposed to as many humane modes of learning as possible. In addition, the students agreed that alternative teaching methods for training in veterinary science can reinforce existing knowledge that is required at the clinical stage, and that they can be effective supplements to traditional training methods. It was also concluded from the study that the use of new alternative approaches is very much appreciated by the students, whereas the validity and effectiveness of these methods are debatable, suggesting that further optimisation, proper application and evaluation of these alternative methods is required.

Risk assessment of feed components of botanical origin - Approaches taken in the European Union.

In view of a continuous trend in replacing synthetic feed additives and especially flavouring compounds by botanical preparations, different aspects of the safety evaluations of plants and plant-derived preparations and components in feed are discussed. This includes risk assessment approaches developed by the European Food Safety Authority (EFSA) for phytotoxins regarding unintentional exposure of target animals and of consumers to animal derived food via carry-over from feed. Relevant regulatory frameworks for feed additives and feed contaminants in the European Union are summarised and the essentials of existing guidelines used in the safety evaluation of botanicals and their preparations and components in feed are outlined. The examples presented illustrate how the safety of the botanicals, their preparations and components present in feed is assessed. An outlook on possible future developments in risk assessment by applying new in vitro and in silico methodologies is given.

Safety for the user of the feed additive consisting of ferric tyrosine chelate (TYFER™) for chickens, turkeys and minor poultry species for fattening or reared for laying/breeding (Akeso Biomedical, Inc).

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP Panel) was asked to deliver a scientific opinion on the safety for the users of the feed additive consisting of ferric tyrosine chelate (TYFER™) when used as a zootechnical additive for chickens, turkeys and minor poultry species for fattening or reared for laying/breeding. The European Commission request follows a previous opinion of the FEEDAP Panel. In that opinion, the Panel identified several risks for the users of the additive; it was listed that it posed a risk to users by inhalation, should be considered as an irritant to skin, eyes and mucous membranes, and also that, due to its nickel content, should be considered as a dermal and respiratory sensitiser. In the current application, the applicant proposed a maximum content of nickel (50 mg/kg). No changes in the manufacturing process have been reported by the applicant. In the absence of new data, the FEEDAP Panel reiterates its previous conclusion that the additive should be as an irritant to skin, eyes and mucous membranes and as a dermal and respiratory sensitiser.

Assessment of the feed additive consisting of Patent Blue V for all non-food-producing animal species for the renewal of its authorisation (Versele-Laga NV).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Patent Blue V as a sensory feed additive for non-food-producing animals. The additive is already authorised for use with non-food-producing animals. The applicant has not provided evidence that the additive currently on the market complies with the existing conditions of authorisation. The FEEDAP Panel cannot conclude whether the additive remains safe for the target species due to the non-compliance with the specifications and the lack of adequate data on the potential aneugenicity of the additive. In the absence of data, the FEEDAP Panel cannot conclude on the potential of the additive to be a dermal and eye irritant nor a dermal and respiratory sensitiser. Since the potential genotoxicity of the additive was not ruled out, the exposure to the additive of the unprotected users should be minimised. The Panel retains that the previously made conclusion on the efficacy remains valid.

Safety and efficacy of a feed additive consisting of an essential oil obtained from the wood of Juniperus deppeana Steud. (cedarwood Texas oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil obtained from the wood of Juniperus deppeana Steud. (cedarwood Texas oil), when used as a sensory additive for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the essential oil under assessment is safe up to the maximum proposed use levels in complete feed of 15 mg/kg for veal calves (milk replacer), cattle for fattening, sheep, goats, horses, dogs, salmonids and ornamental fish. For the other species, the calculated safe concentrations in complete feed were 5 mg/kg for chickens for fattening, 8 mg/kg for laying hens, 7 mg/kg for turkeys for fattening, 10 mg/kg for piglets, 12 mg/kg for pigs for fattening, 14 mg/kg for sows and dairy cows, 8.5 mg/kg for rabbits and 4 mg/kg for cats. These conclusions were extrapolated to other physiologically related species. For any other species, the additive was considered safe at 4 mg/kg complete feed. The use of cedarwood Texas oil in water for drinking was considered safe provided that the total daily intake of the additive does not exceed the daily amount that is considered safe when consumed via feed. No concerns for consumers and the environment were identified following the use of the additive up to the maximum proposed use level in feed. The additive under assessment should be considered as irritant to skin and eyes, and as a skin and respiratory sensitiser. Since the individual components of cedarwood Texas oil are recognised to flavour food and their function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Consumer safety of feed additives containing selenium.

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety for the consumer of products from animals fed diets with feed additives containing selenium as an active substance. Based on the limited data set available and the several uncertainties, the FEEDAP Panel concluded that the use of organic selenium at the currently maximum authorised use level of 0.2 mg supplemented selenium from organic sources/kg complete feed (within a maximum of 0.5 mg total selenium/kg complete feed) leads to an exceedance of the UL for all the population categories (except elderly and very elderly), suggesting a concern for consumer safety. It was not possible to conclude on the safety of the currently maximum use level of 0.5 mg total selenium/kg complete feed for all consumer categories. Additional data from studies specifically designed to measure deposition of selenium in tissues and products from animal origin resulting from the use of the different sources of selenium would be required to perform a proper risk assessment.

Safety of a feed additive consisting of endo 1,4 ß-d-mannanase produced by Thermothelomyces thermophilus DSM 33149 (Natupulse® TS/TS L) for chickens and turkeys for fattening, minor poultry species for fattening and ornamental birds (BASF SE).

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 of a feed additive consisting of endo-1,4-ß-d-mannanase produced by Thermothelomyces thermophilus DSM 33149, intended for use as a zootechnical additive (functional group: digestibility enhancers) for chickens for fattening, turkeys for fattening, minor poultry species for fattening and ornamental birds. The safety and efficacy of the additive have been already assessed previously; however, the FEEDAP Panel could not conclude on the safety of the additive for the target species, consumers and the users due to lack of reliable data on the potential genotoxicity of the additive. In the present assessment, the applicant submitted a new in vitro mammalian cell micronucleus test. After the assessment of the data newly submitted, the FEEDAP Panel concluded that the use of the feed additive in animal nutrition under the conditions of use proposed is of no concern for target species and consumer safety. The additive is not irritant to the eyes or skin. Owing to the proteinaceous nature of the active substance, the additive should be considered a respiratory sensitiser. The Panel cannot conclude on the potential of the additive to be a skin sensitiser.

Safety and efficacy of a feed additive consisting of lanthanum carbonate octahydrate for dogs (Porus GmbH).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of lanthanum carbonate octahydrate as a zootechnical feed additive for dogs. The additive is already authorised for use in feed for cats. The FEEDAP Panel concluded that the additive lanthanum carbonate octahydrate is safe for adult dogs at the maximum recommended level of 7500 mg/kg complete feed. The additive is not irritant to skin or eyes, is not a skin sensitiser and exposure by inhalation is considered to be unlikely. The Panel also concluded that lanthanum carbonate octahydrate is efficacious in the reduction of phosphorus bioavailability in adult dogs at the minimum inclusion level of 1500 mg/kg complete feed.

Assessment of the feed additive consisting of Enterococcus lactisNCIMB 10415 (Cylactin®) for cats and dogs for the renewal of its authorisation (DSM Nutritional Products 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 the authorisation of Cylactin® as a zootechnical feed additive for cats and dogs. The active agent of the additive is Enterococcus lactis NCIMB 10415 and the micro-encapsulated formulation, Cylactin® LBC ME5 PET, was assessed. The applicant has provided evidence that the additive currently on the market complies with the existing conditions of authorisation. The Panel concluded that the additive remains safe for cats and dogs. Regarding user safety, the additive was not shown to be skin and eye irritant, but it should be considered a respiratory sensitiser. No conclusions can be drawn on the skin sensitisation. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Modification of the terms of authorisation regarding the maximum inclusion level of a feed additive consisting of 4-hydroxy-2,5-dimethylfuran-3(2H)-one for cats and dogs (V. MANE FILS).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the proposed modification of the terms of the authorisation regarding the maximum inclusion level of a feed additive consisting of 4-hydroxy-2,5-dimethylfuran-3(2H)-one for cats and dogs. 4-Hydroxy-2,5-dimethylfuran-3(2H)-one is currently authorised for use as a sensory additive (functional group: flavouring compounds) for cats and dogs at a recommended maximum content of 5 mg/kg complete feed. The applicant is requesting a modification of the authorisation to increase the recommended maximum content of the additive up to 25 mg/kg complete feed for cats and dogs. Based on the toxicological data available, the FEEDAP Panel concludes that 4-hydroxy-2,5-dimethylfuran-3(2H)-one is safe for dogs at 25 mg/kg feed and for cats at 18 mg/kg feed. The additive is irritant to skin, eyes and to the respiratory tract and is a skin sensitiser. No further demonstration of efficacy is necessary.

Safety and efficacy of a feed additive consisting of 6-phytase produced with Trichoderma reesei (CBS 126897) (Quantum® Blue) for fin fish (ROAL Oy).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of 6-phytase (Quantum® Blue) as a zootechnical feed additive for fin fish. The additive is authorised for use in poultry and pigs. The additive is available in solid and liquid forms, and the 6-phytase contained in the product is produced by fermentation with a genetically modified strain of Trichoderma reesei. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the genetic modification of the production strain does not give rise to safety concerns; viable cells of the production strain and its DNA were not detected in the final products. The FEEDAP Panel concluded that, based on the data available, the additive tested is safe for fin fish at the highest recommended level of 2500 phytase activity unit (FTU)/kg complete feed. The Panel concluded that Quantum® Blue is not an irritant to skin and eyes nor a skin sensitiser. Owing to the proteinaceous nature of the active substance, 6-phytase (Quantum® Blue) is considered a respiratory sensitiser. The use of Quantum® Blue as a feed additive is considered safe for the environment. The additive is considered to be efficacious as a zootechnical additive for salmonids and ornamental fish at 500 FTU/kg complete feed and other fin fish at 2500 FTU/kg complete feed.

Safety and efficacy of a feed additive consisting of muramidase produced with Trichoderma reesei DSM 32338 (Balancius™) for laying hens (DSM nutritional products).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of muramidase produced with Trichoderma reesei DSM 32338 (Balancius™) as a feed additive for laying hens. The additive is already authorised as a zootechnical additive (functional group: other zootechnical additives) for chickens, turkeys and minor poultry species for fattening or reared for breeding, and for weaned piglets. The enzyme is produced by fermentation with a genetically modified strain of Trichoderma reesei; viable cells of the production strain and its recombinant DNA were not detected in the additive. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the additive does not give rise to safety concerns regarding the genetic modification of the production strain. Based on the data available from a sub-chronic oral toxicity study, the Panel concluded that the additive is safe for laying hens at the maximum recommended level of 60,000 LSU(F) (muramidase activity units)/kg feed. The Panel also concluded that the additive is safe for the consumers and the environment. The liquid formulation of the additive is considered not irritant to the skin or eyes. The solid formulation of the additive is considered not irritant to the skin. The Panel cannot conclude on the potential of the additive (both formulations) to be a dermal sensitiser or on the potential of the solid formulation to be irritant to the eyes. Due to the proteinaceous nature, both forms of the additive should be considered respiratory sensitisers. The additive has the potential to be efficacious as a zootechnical additive for laying hens at 30,000 LSU(F)/kg feed.

Safety and efficacy of a feed additive consisting of 6-phytase produced by Aspergillus oryzae DSM 33737 (HiPhorius™) for all poultry, all Suidae and all fin fish (DSM Nutritional Products Ltd).

Following a request from the European Commission, the EFSA 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 6-phytase produced by the genetically modified strain Aspergillus oryzae DSM 33737 (HiPhorius™ 10, 40, 20L and 50L) as a zootechnical feed additive for all poultry, all Suidae and all fin fish. The FEEDAP Panel concluded that the genetic modification of the production strain does not give rise to safety concerns. Based on the no observed adverse effect level identified in a subchronic oral toxicity study in rats, the additive was considered safe for all poultry, all Suidae and all fin fish at the proposed conditions of use. The Panel also concluded that the use of the product as a feed additive is of no concern for the consumers and the environment. The liquid formulations of the additive are not skin or eye irritants. The two solid ones are not skin irritants but are eye irritants. Owing to the lack of data, the Panel cannot conclude on the skin sensitisation of the final formulations of the additive. Due to the proteinaceous nature of the active substance (6-phytase), the additive is considered a respiratory sensitiser. The Panel concludes that the additive is efficacious when included in the diet of poultry for fattening or reared for laying/breeding, reproductive Suidae, and all fin fish. Due to the lack of sufficient data, the Panel could not conclude on the efficacy for laying and reproductive poultry and growing Suidae.

Safety and efficacy of a feed additive consisting of sodium bisulphate for all animal species except aquatic animals (Grillo Werke AG & Jones-Hamilton Co.).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application for renewal of authorisation of sodium bisulphate (SBS) as a feed additive for all terrestrial animal species (category: technological additive; functional group: preservative), and for all terrestrial animal species other than cats, mink, pets and other non-food-producing animals (category: technological additive; functional group: acidity regulator). EFSA has also been asked to assess the new use of the product as an acidity regulator and flavouring compound in all pets and other non-food-producing animals except aquatic animals. The applicant provided evidence that the additive currently in the market complies with the existing conditions of authorisation. There is no evidence that would lead the FEEDAP Panel to reconsider its previous conclusions. Thus, the Panel concluded that the additive remains safe for all terrestrial animal species, consumer and the environment under the authorised conditions of use. The FEEDAP Panel considers that the proposed new use would not introduce risks not already considered in the previous assessment and therefore the same conclusions on all terrestrial animal species, consumers of products from animals fed the additive and the environment would apply. Regarding user safety, the additive is irritant to the skin, eyes and the respiratory tract, and should be considered a skin and respiratory sensitiser. There is no need to assess the efficacy of the additive in the context of the renewal of the authorisation. The Panel considers that the additive has the potential to be efficacious as an acidity regulator and sensory additive (flavouring compound) in feed for pet and non-food-producing animals (except aquatic animals).

Modification of the terms of authorisation regarding the maximum inclusion level of a feed additive consisting of nonanoic acid for all pigs and poultry species (Anitox Corporation).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the proposed modification of the terms of the authorisation regarding the maximum inclusion level of a feed additive consisting of nonanoic acid for all pigs and poultry species. Nonanoic acid is currently authorised for use as a sensory additive (functional group: flavouring compounds) for all animal species at a recommended maximum content of 5 mg/kg complete feed. The applicant is requesting a modification of the authorisation to increase the recommended maximum content of the active substance from 5 to 100 mg/kg complete feed for all poultry and pig species. In support of the safety of the additive at the new proposed level, the applicant provided tolerance trials in the target species. The FEEDAP Panel concludes that nonanoic acid is safe for all growing poultry species and Suidae at 100 mg/kg feed. The Panel cannot conclude on the safety of the new proposed level (100 mg/kg complete feed) for laying hens, turkeys for breeding, minor poultry species for laying/breeding and reproductive Suidae. However, FEEDAP Panel considered that nonanoic acid is safe at 10 mg/kg complete feed in laying hens, turkeys for breeding, minor poultry species for laying/breeding and 20 mg/kg complete feed for reproductive Suidae. The use of the feed additive in animal nutrition under the conditions of use proposed is of no concern for the consumer and the environment. Due to the lack of data, the FEEDAP Panel cannot conclude on the potential of the additive to be a skin and eye irritant neither a dermal nor respiratory sensitiser. No further demonstration of efficacy is necessary.

Safety and efficacy of a feed additive consisting of fumonisin esterase produced with Komagataella phaffii NCAIM (P) Y001485 for all pigs (piglets, pigs for fattening, sows and minor growing and reproductive porcine species) (Dr. Bata Ltd.).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of the additive based on fumonisin esterase (Free Yeast® F), produced with a genetically modified strain of Komagataella phaffii. The additive is categorised as a technological feed additive, for the reduction of the contamination of feed by mycotoxins and intended for use in all pigs species (piglets, pigs for fattening, sows and minor growing and reproductive porcine species). It was shown that the production strain and its recombinant genes are not present in the additive. The FEEDAP Panel concluded that the additive is safe for weaned and suckling piglets and pigs for fattening, and all minor growing porcine species up to 60 U/kg complete feed. No conclusions can be drawn on the safety of the additive in sows. The use of the additive in animal nutrition is of no concern for consumer safety. The additive is dust-free, and therefore, respiratory sensitisation/irritation is unlikely. The additive is non-irritant to the eyes and the skin. No conclusion could be made on skin sensitisation. The use of the additive as a feed additive is considered safe for the environment. The Panel concluded that the additive is efficacious as technological feed additive for the reduction of feed contamination by fumonisins, when used at the minimum recommended concentration of 60 U/kg. This conclusion can be extrapolated to all growing and reproductive pigs and other minor porcine species.