The use of testing strategies which incorporate a range of alternative methods and which use anim... more The use of testing strategies which incorporate a range of alternative methods and which use animals only as a last resort is widely considered to provide a reliable way of predicting chemical toxicity while minimising animal testing. The widespread concern over the severity of the Draize rabbit test for assessing skin irritation and corrosion led to the proposal of a stepwise testing strategy at an OECD workshop in January 1996. Subsequently, the proposed testing strategy was adopted, with minor modifications, by the OECD Advisory Group on Harmonization of Classification and Labelling. This article reports an evaluation of the proposed OECD testing strategy as it relates to the classification of skin corrosives. By using a set of 60 chemicals, an assessment was made of the effect of applying three steps in the strategy, taken both individually and in sequence. The results indicate that chemicals can be classified as corrosive (C) or non-corrosive (NC) with sufficient reliability by...
This is the report of a meeting organised jointly by the UK Government and the European Centre fo... more This is the report of a meeting organised jointly by the UK Government and the European Centre for the Validation of Alternative Methods (ECVAM), a unit of the European Commission (EC) Joint Research Centre, based at Ispra, Italy. The meeting, on Progress in Toxicological Testing, was held in London, UK, on 12–13 May 1998, to coincide with the UK Presidency of the European Union (EU). The principal aim was to reach agreement on ways to further reduce and refine the use of animals in the toxicity testing of chemicals and pesticides within the current regulatory framework, without compromising human safety. The meeting was organised to promote discussion on the use of animals in toxicological testing, and to define the number of specific and realistic recommendations which could feasibly be achieved within a relatively short time-scale, via the appropriate European and/or international authorities. The meeting arose from discussions between the UK Health and Safety Executive (HSE) and ECVAM. It was felt that there would be some value in organising a relatively informal meeting between some of the key individuals in the EU Member States who are active in promoting reduction and refinement aspects in relation to the use of animals for toxicity testing, outside of the formal EC Competent Authority meetings. The meeting was organised by an HSE-led working group, which included representatives of key UK Government departments (HSE, the Home Office, and ATLA 26, 619–627, 1998 619
-ECVAM sponsored a formal validation study on three in vitro tests for skin irritation, of which ... more -ECVAM sponsored a formal validation study on three in vitro tests for skin irritation, of which two employ reconstituted human epidermis models (EPISKIN™, EpiDerm™), and one, the skin integrity function test (SIFT), employs ex vivo mouse skin. The goal of the study was to assess whether the in vitro tests would correctly predict in vivo classifications according to the EU classification scheme, "R38" and "no label" (i.e. non-irritant). 58 chemicals (25 irritants and 33 non-irritants) were tested, having been selected to give broad coverage of physico-chemical properties, and an adequate distribution of irritancy scores derived from in vivo rabbit skin irritation tests. In Phase 1, 20 of these chemicals (9 irritants and 11 nonirritants) were tested with coded identities by a single lead laboratory for each of the methods, to confirm the suitability of the protocol improvements introduced after a prevalidation phase. When cell viability (evaluated by the MTT reduction test) was used as the endpoint, the predictive ability of both EpiDerm and EPISKIN was considered sufficient to justify their progression to Phase 2, while the predictive ability of the SIFT was judged to be inadequate. Since both the reconstituted skin models provided false predictions around the in vivo classification border (a rabbit Draize test score of 2), the release of a cytokine, interleukin-1α (IL-1α), was also determined. In Phase 2, each human skin model was tested in three laboratories, with 58 chemicals. The main endpoint measured for both EpiDerm and EPISKIN was cell viability. In samples from chemicals which gave MTT assay results above the threshold of 50% viability, IL-1α release was also measured, to determine whether the additional endpoint would improve the predictive ability of the tests. For EPISKIN, the sensitivity was 75% and the specificity was 81% (MTT assay only); with the combination of the MTT and IL-1α assays, the sensitivity increased to 91%, with a specificity of 79%. For EpiDerm, the sensitivity was 57% and the specificity was 85% (MTT assay only), while the predictive capacity of EpiDerm was not improved by the measurement of IL-1α release. Following independent peer review, in April 2007 the ECVAM Scientific Advisory Committee endorsed the scientific validity of the EPISKIN test as a replacement for the rabbit skin irritation method, and of the EpiDerm method for identifying skin irritants as part of a tiered testing strategy. This new alternative approach will probably be the first use of in vitro toxicity testing to replace the Draize rabbit skin irritation test in Europe and internationally, since, in the very near future, new EU and OECD Test Guidelines will be proposed for regulatory acceptance.
... 6 Klaus Cussler,7 Arnold Daas,4 Johan Descamps,8 Roland Dobbelaer,9 Julia Fentem,5 Marlies Ha... more ... 6 Klaus Cussler,7 Arnold Daas,4 Johan Descamps,8 Roland Dobbelaer,9 Julia Fentem,5 Marlies Halder,5 Margot van der Kamp ... The partici-pants, all experts in vaccine quality control and/or validation procedures, came from international regulatory or government organisations ...
The preliminary conclusions of a survey of possible non-animal alternatives to the Draize rabbit ... more The preliminary conclusions of a survey of possible non-animal alternatives to the Draize rabbit eye irritancy test, recently conducted for the Commission of the European Communities, are presented. The various types of alternatives to animal tests are reviewed in terms of their current state of development and validation, and also their potential in relation to the type of exposure, level of testing, type of testing, type of effect, location of effect, and type of test material. Various problems concerning the availability and quality of in vivo eye irritation data, and the use of this data in in vitro/in vivo comparisons, are highlighted. Finally, the use of step-wise and integrated animal/non-animal and non-animal/non-animal test systems and strategies are discussed.
This is the report of the thirty-first of a series of workshops organised by the European Centre ... more This is the report of the thirty-first of a series of workshops organised by the European Centre for the Validation of Alternative Methods (ECVAM). ECVAMs main goal, as defined in 1993 by its Scientific Advisory Committee, is to promote the scientific and regulatory acceptance of alternative methods which are of importance to the biosciences and which reduce, refine or replace the use of laboratory animals. One of the first priorities set by ECVAM was the implementation of procedures which would enable it to become well-informed about the state-of-the-art of non-animal test development and validation, and the potential for the possible incorporation of alternative tests into regulatory procedures. It was decided that this would be best achieved by the organisation of ECVAM workshops on specific topics, at which small groups of invited experts would review the current status of various types of in vitro tests and their potential uses, and make recommendations about the best ways for...
Toxicity testing is conducted to determine the potential human health hazards of chemicals and pr... more Toxicity testing is conducted to determine the potential human health hazards of chemicals and products. Acute systemic toxicity testing is used to properly classify and appropriately label materials with regard to their lethality potential in accordance with established regulatory requirements (49 CFR 173; 16 CFR 1500; 29 CFR 1910; 40 CFR 156). Non-lethal parameters may also be evaluated in acute systemic toxicity studies to identify potential target organ toxicity, toxicokinetic parameters, and dose-response relationships. While animals are currently used to evaluate acute toxicity, recent studies suggest that in vitro methods may also be helpful in predicting acute toxicity.
ECVAM's role in the practical validation of replacement alternative methods for use in regula... more ECVAM's role in the practical validation of replacement alternative methods for use in regulatory testing is reviewed, including an outline of the criteria which have been used in determining ECVAM's priorities. Some of the difficulties which have arisen in validation studies are discussed, and solutions to these are proposed, with particular emphasis on ensuring that methods are sufficiently well-developed to enter the validation process, and on the ECVAM prevalidation scheme for encouraging protocol optimisation and the prior assessment of interlaboratory transferability. Comments are made on problems encountered in selecting test materials backed by adequate in vivo data and in undertaking appropriate in vivo/in vitro comparisons.
Non-animal procedures, including in vitro test systems and test strategies, can already make a si... more Non-animal procedures, including in vitro test systems and test strategies, can already make a significant contribution to the background to risk assessment — in predicting both the toxic potential and toxic potency of chemicals, as well as, in some circumstances, the toxic hazard they may represent under specified conditions of exposure. They can be particularly useful for investigating molecular and cellular mechanisms of chemical-induced toxicity, and for identifying species-specific effects, which greatly limit the value of data from laboratory animal studies in the human risk assessment process. Attention is focused on the need for greater effort to be invested in the development of non-animal procedures for evaluating the biokinetic factors which will determine the ultimate form and concentration of a particular chemical at possible sites of toxic action. The relative merits of correlative and mechanistic approaches to test development and test validation are discussed. The need for realism is emphasised, not only in relation to our expectations of the validation process, but also in terms of the current and future status of regulatory toxicology, in vitro or in vivo, as a scientific discipline. Finally, it is concluded that the intelligent and strategic use of in vitro test systems, in conjunction with predictive computer modelling, could markedly improve the scientific basis of human risk assessment.
Laws that mandate replacement alternatives, reduction alternatives, and refinement alternatives (... more Laws that mandate replacement alternatives, reduction alternatives, and refinement alternatives (the Three Rs) in scientific research have been passed in the United Kingdom, Germany, the Netherlands, the United States, and the European Union over the past decade. Full implementation of this newly developed legislation depends upon scientists' ability to understand animal welfare issues and to accept the legitimacy of the public's interest in the conduct of science. The European Centre for the Validation of Alternative Methods (ECVAM), established by the European Commission in 1991 to promote the scientific and regulatory acceptance of alternative methods, recently sponsored a workshop to discuss the current status of the Three Rs and to make recommendations aimed at achieving greater acceptance of the concept of humane experimental technique. Twenty-one scientists professionally committed to the Three Rs were invited to attend the conference, which was chaired by Michael Balls, head of ECVAM, and Alan M. Goldberg, director of the Johns Hopkins Center for Alternatives to Animal Testing (CAAT). The conference was held in Sheringham, Norfolk, UK on May 30, 1995-June 3, 1995. A report based on the conference was published by ECVAM (1) in December 1995 and is excerpted as follows. Origins of the Three Rs The Three Rs originated in a proposal made in 1954 by Charles Hume, founder of the Universities Federation for Animal Welfare (UFAW), that the UFAW should undertake a scientific study of humane technique in laboratory animal experiments. The project was managed by a committee under the chairmanship of Sir Peter Medawar, the Nobel prize winning immunologist, with William Lane-Petter, Secretary of the Research Defence Society of Great Britain, among its members. Christine Stevens, founder of the Animal Welfare Institute (AWI) in the U.S., provided financial support for the project. W.M.S. Russell, a zoologist, and R. L. Burch, a microbiologist, were appointed to carry out the work, which led to the publication of the book The Principles of Humane Experimental Technique (2) in 1959. At the time of the book's publication, Charles Hume commented that
Biochemical and Biophysical Research Communications, 1991
A major novel coumarin metabolite was isolated from rat hepatic microsomal incubations by high-pe... more A major novel coumarin metabolite was isolated from rat hepatic microsomal incubations by high-performance liquid chromatography. In the presence of a rat liver cytosolic fraction and NADH it was rapidly metabolized to O-hydroxyphenylethanol. The metabolite co-chromatographed with an authentic sample of O-hydroxyphenylacetaldehyde and its identity was confirmed by mass spectral analysis. The formation of O-hydroxyphenylacetaldehyde from coumarin was NADPH-dependent. It was the major metabolite formed by rat, gerbil and human liver microsomes at a coumarin concentration of 1mM.
Experience has shown that the outcome of large and expensive validation studies on alternative me... more Experience has shown that the outcome of large and expensive validation studies on alternative methods can be compromised if their managers do not insist that optimised test protocols and proof of their performance are submitted before the start of the formal validation study. One way for the sponsors of validation studies to confirm both the likely relevance of a method for its stated purpose and its readiness for validation would be to require a prevalidation study before formal validation was contemplated. This process would involve the developers (or other proponents of the method) and selected independent laboratories in protocol refinement (Phase I) and protocol transfer (Phase II). The optimised protocol would then be assessed in a protocol performance phase (Phase III), which would involve the testing of a relevant set of coded test materials and an evaluation of a proposed prediction model. In certain circumstances, a successful outcome of Phase III might be sufficient for promotion of the regulatory acceptance of the method. Normally, however, the method would proceed to a formal validation study. The European Centre for the Validation of Alternative Methods, a recognised validation authority, now proposes to introduce this prevalidation scheme into its validation strategy.
This is the report of the twenty-second of a series of workshops organised by the European Centre... more This is the report of the twenty-second of a series of workshops organised by the European Centre for the Validation of Alternative Methods (ECVAM). ECVAM's main goal, as defined in 1993 by its Scientific Advisory Committee, is to promote the scientific and regulatory acceptance of alternative methods which are of importance to the biosciences and which reduce, refine or replace the use of laboratory animals. One of the first priorities set by ECVAM was the implementation of procedures which would enable it to become well-informed about the state-of-the-art of non-animal test development and validation, and the potential for the possible incorporation of alternative tests into regulatory procedures. It was decided that this would be best achieved by the organisation of ECVAM workshops on specific topics, at which small groups of invited experts would review the current status of various types of in vitro tests and their potential uses, and make recommendations about the best ways forward (1).
With regard to the problems encountered and the experience gained in validation studies conducted... more With regard to the problems encountered and the experience gained in validation studies conducted in the past, suggestions have been made concerning criteria for the selection of the tests and laboratories to be included in a validation study, the selection and distribution of test chemicals, and procedures for the handling, analysis and interpretation of the resulting data. In particular, tests
Toxicology in vitro : an international journal published in association with BIBRA, 1994
The use of in vitro techniques in toxicological research is widespread, but, up to now, relativel... more The use of in vitro techniques in toxicological research is widespread, but, up to now, relatively little progress has been made in applying the knowledge gained in regulatory toxicity testing. In vitro tests should be accepted into regulatory toxicology for at least five reasons: scientific, humanitarian, legislative, logistical and economic. In particular, in vitro tests have the potential to provide a mechanistic basis for toxicity testing, and they may permit the use of tissues from more-appropriate target species and individuals, including humans. The relevance and reliability of the in vitro test, with regard to its use for a particular purpose and with particular types of chemicals, should have been adequately demonstrated (i.e. it should have been validated) prior to regulatory acceptance. There are several obstacles to this, including whether validation should be based on comparisons between in vitro data and animal data, and whether the in vitro tests should be expected to...
This study compared five methods, the isolated rabbit eye (IRE), bovine corneal opacity and perme... more This study compared five methods, the isolated rabbit eye (IRE), bovine corneal opacity and permeability (BCOP), EpiOcular, fluorescein leakage (FL) and neutral red release (NRR) assays, for predicting the eye irritation potential of hair-care formulations. Ten shampoo and seven conditioner formulations of known ocular irritation potential were tested. Each group included a market-acceptable formulation as a comparative benchmark. Predictions of ocular irritation were made by using classification models (IRE, BCOP and EpiOcular assays) or by direct comparison with benchmarks (IRE, EpiOcular, FL and NRR assays). The BCOP assay was less sensitive than the IRE test in discriminating between formulations of different irritation potentials, and did not perform as well as the other assays in identifying mild formulations. All of the assays appeared to be better at discriminating correctly between the shampoos than between the conditioners. The EpiOcular assay showed the closest concordanc...
The use of testing strategies which incorporate a range of alternative methods and which use anim... more The use of testing strategies which incorporate a range of alternative methods and which use animals only as a last resort is widely considered to provide a reliable way of predicting chemical toxicity while minimising animal testing. The widespread concern over the severity of the Draize rabbit test for assessing skin irritation and corrosion led to the proposal of a stepwise testing strategy at an OECD workshop in January 1996. Subsequently, the proposed testing strategy was adopted, with minor modifications, by the OECD Advisory Group on Harmonization of Classification and Labelling. This article reports an evaluation of the proposed OECD testing strategy as it relates to the classification of skin corrosives. By using a set of 60 chemicals, an assessment was made of the effect of applying three steps in the strategy, taken both individually and in sequence. The results indicate that chemicals can be classified as corrosive (C) or non-corrosive (NC) with sufficient reliability by...
This is the report of a meeting organised jointly by the UK Government and the European Centre fo... more This is the report of a meeting organised jointly by the UK Government and the European Centre for the Validation of Alternative Methods (ECVAM), a unit of the European Commission (EC) Joint Research Centre, based at Ispra, Italy. The meeting, on Progress in Toxicological Testing, was held in London, UK, on 12–13 May 1998, to coincide with the UK Presidency of the European Union (EU). The principal aim was to reach agreement on ways to further reduce and refine the use of animals in the toxicity testing of chemicals and pesticides within the current regulatory framework, without compromising human safety. The meeting was organised to promote discussion on the use of animals in toxicological testing, and to define the number of specific and realistic recommendations which could feasibly be achieved within a relatively short time-scale, via the appropriate European and/or international authorities. The meeting arose from discussions between the UK Health and Safety Executive (HSE) and ECVAM. It was felt that there would be some value in organising a relatively informal meeting between some of the key individuals in the EU Member States who are active in promoting reduction and refinement aspects in relation to the use of animals for toxicity testing, outside of the formal EC Competent Authority meetings. The meeting was organised by an HSE-led working group, which included representatives of key UK Government departments (HSE, the Home Office, and ATLA 26, 619–627, 1998 619
-ECVAM sponsored a formal validation study on three in vitro tests for skin irritation, of which ... more -ECVAM sponsored a formal validation study on three in vitro tests for skin irritation, of which two employ reconstituted human epidermis models (EPISKIN™, EpiDerm™), and one, the skin integrity function test (SIFT), employs ex vivo mouse skin. The goal of the study was to assess whether the in vitro tests would correctly predict in vivo classifications according to the EU classification scheme, "R38" and "no label" (i.e. non-irritant). 58 chemicals (25 irritants and 33 non-irritants) were tested, having been selected to give broad coverage of physico-chemical properties, and an adequate distribution of irritancy scores derived from in vivo rabbit skin irritation tests. In Phase 1, 20 of these chemicals (9 irritants and 11 nonirritants) were tested with coded identities by a single lead laboratory for each of the methods, to confirm the suitability of the protocol improvements introduced after a prevalidation phase. When cell viability (evaluated by the MTT reduction test) was used as the endpoint, the predictive ability of both EpiDerm and EPISKIN was considered sufficient to justify their progression to Phase 2, while the predictive ability of the SIFT was judged to be inadequate. Since both the reconstituted skin models provided false predictions around the in vivo classification border (a rabbit Draize test score of 2), the release of a cytokine, interleukin-1α (IL-1α), was also determined. In Phase 2, each human skin model was tested in three laboratories, with 58 chemicals. The main endpoint measured for both EpiDerm and EPISKIN was cell viability. In samples from chemicals which gave MTT assay results above the threshold of 50% viability, IL-1α release was also measured, to determine whether the additional endpoint would improve the predictive ability of the tests. For EPISKIN, the sensitivity was 75% and the specificity was 81% (MTT assay only); with the combination of the MTT and IL-1α assays, the sensitivity increased to 91%, with a specificity of 79%. For EpiDerm, the sensitivity was 57% and the specificity was 85% (MTT assay only), while the predictive capacity of EpiDerm was not improved by the measurement of IL-1α release. Following independent peer review, in April 2007 the ECVAM Scientific Advisory Committee endorsed the scientific validity of the EPISKIN test as a replacement for the rabbit skin irritation method, and of the EpiDerm method for identifying skin irritants as part of a tiered testing strategy. This new alternative approach will probably be the first use of in vitro toxicity testing to replace the Draize rabbit skin irritation test in Europe and internationally, since, in the very near future, new EU and OECD Test Guidelines will be proposed for regulatory acceptance.
... 6 Klaus Cussler,7 Arnold Daas,4 Johan Descamps,8 Roland Dobbelaer,9 Julia Fentem,5 Marlies Ha... more ... 6 Klaus Cussler,7 Arnold Daas,4 Johan Descamps,8 Roland Dobbelaer,9 Julia Fentem,5 Marlies Halder,5 Margot van der Kamp ... The partici-pants, all experts in vaccine quality control and/or validation procedures, came from international regulatory or government organisations ...
The preliminary conclusions of a survey of possible non-animal alternatives to the Draize rabbit ... more The preliminary conclusions of a survey of possible non-animal alternatives to the Draize rabbit eye irritancy test, recently conducted for the Commission of the European Communities, are presented. The various types of alternatives to animal tests are reviewed in terms of their current state of development and validation, and also their potential in relation to the type of exposure, level of testing, type of testing, type of effect, location of effect, and type of test material. Various problems concerning the availability and quality of in vivo eye irritation data, and the use of this data in in vitro/in vivo comparisons, are highlighted. Finally, the use of step-wise and integrated animal/non-animal and non-animal/non-animal test systems and strategies are discussed.
This is the report of the thirty-first of a series of workshops organised by the European Centre ... more This is the report of the thirty-first of a series of workshops organised by the European Centre for the Validation of Alternative Methods (ECVAM). ECVAMs main goal, as defined in 1993 by its Scientific Advisory Committee, is to promote the scientific and regulatory acceptance of alternative methods which are of importance to the biosciences and which reduce, refine or replace the use of laboratory animals. One of the first priorities set by ECVAM was the implementation of procedures which would enable it to become well-informed about the state-of-the-art of non-animal test development and validation, and the potential for the possible incorporation of alternative tests into regulatory procedures. It was decided that this would be best achieved by the organisation of ECVAM workshops on specific topics, at which small groups of invited experts would review the current status of various types of in vitro tests and their potential uses, and make recommendations about the best ways for...
Toxicity testing is conducted to determine the potential human health hazards of chemicals and pr... more Toxicity testing is conducted to determine the potential human health hazards of chemicals and products. Acute systemic toxicity testing is used to properly classify and appropriately label materials with regard to their lethality potential in accordance with established regulatory requirements (49 CFR 173; 16 CFR 1500; 29 CFR 1910; 40 CFR 156). Non-lethal parameters may also be evaluated in acute systemic toxicity studies to identify potential target organ toxicity, toxicokinetic parameters, and dose-response relationships. While animals are currently used to evaluate acute toxicity, recent studies suggest that in vitro methods may also be helpful in predicting acute toxicity.
ECVAM's role in the practical validation of replacement alternative methods for use in regula... more ECVAM's role in the practical validation of replacement alternative methods for use in regulatory testing is reviewed, including an outline of the criteria which have been used in determining ECVAM's priorities. Some of the difficulties which have arisen in validation studies are discussed, and solutions to these are proposed, with particular emphasis on ensuring that methods are sufficiently well-developed to enter the validation process, and on the ECVAM prevalidation scheme for encouraging protocol optimisation and the prior assessment of interlaboratory transferability. Comments are made on problems encountered in selecting test materials backed by adequate in vivo data and in undertaking appropriate in vivo/in vitro comparisons.
Non-animal procedures, including in vitro test systems and test strategies, can already make a si... more Non-animal procedures, including in vitro test systems and test strategies, can already make a significant contribution to the background to risk assessment — in predicting both the toxic potential and toxic potency of chemicals, as well as, in some circumstances, the toxic hazard they may represent under specified conditions of exposure. They can be particularly useful for investigating molecular and cellular mechanisms of chemical-induced toxicity, and for identifying species-specific effects, which greatly limit the value of data from laboratory animal studies in the human risk assessment process. Attention is focused on the need for greater effort to be invested in the development of non-animal procedures for evaluating the biokinetic factors which will determine the ultimate form and concentration of a particular chemical at possible sites of toxic action. The relative merits of correlative and mechanistic approaches to test development and test validation are discussed. The need for realism is emphasised, not only in relation to our expectations of the validation process, but also in terms of the current and future status of regulatory toxicology, in vitro or in vivo, as a scientific discipline. Finally, it is concluded that the intelligent and strategic use of in vitro test systems, in conjunction with predictive computer modelling, could markedly improve the scientific basis of human risk assessment.
Laws that mandate replacement alternatives, reduction alternatives, and refinement alternatives (... more Laws that mandate replacement alternatives, reduction alternatives, and refinement alternatives (the Three Rs) in scientific research have been passed in the United Kingdom, Germany, the Netherlands, the United States, and the European Union over the past decade. Full implementation of this newly developed legislation depends upon scientists' ability to understand animal welfare issues and to accept the legitimacy of the public's interest in the conduct of science. The European Centre for the Validation of Alternative Methods (ECVAM), established by the European Commission in 1991 to promote the scientific and regulatory acceptance of alternative methods, recently sponsored a workshop to discuss the current status of the Three Rs and to make recommendations aimed at achieving greater acceptance of the concept of humane experimental technique. Twenty-one scientists professionally committed to the Three Rs were invited to attend the conference, which was chaired by Michael Balls, head of ECVAM, and Alan M. Goldberg, director of the Johns Hopkins Center for Alternatives to Animal Testing (CAAT). The conference was held in Sheringham, Norfolk, UK on May 30, 1995-June 3, 1995. A report based on the conference was published by ECVAM (1) in December 1995 and is excerpted as follows. Origins of the Three Rs The Three Rs originated in a proposal made in 1954 by Charles Hume, founder of the Universities Federation for Animal Welfare (UFAW), that the UFAW should undertake a scientific study of humane technique in laboratory animal experiments. The project was managed by a committee under the chairmanship of Sir Peter Medawar, the Nobel prize winning immunologist, with William Lane-Petter, Secretary of the Research Defence Society of Great Britain, among its members. Christine Stevens, founder of the Animal Welfare Institute (AWI) in the U.S., provided financial support for the project. W.M.S. Russell, a zoologist, and R. L. Burch, a microbiologist, were appointed to carry out the work, which led to the publication of the book The Principles of Humane Experimental Technique (2) in 1959. At the time of the book's publication, Charles Hume commented that
Biochemical and Biophysical Research Communications, 1991
A major novel coumarin metabolite was isolated from rat hepatic microsomal incubations by high-pe... more A major novel coumarin metabolite was isolated from rat hepatic microsomal incubations by high-performance liquid chromatography. In the presence of a rat liver cytosolic fraction and NADH it was rapidly metabolized to O-hydroxyphenylethanol. The metabolite co-chromatographed with an authentic sample of O-hydroxyphenylacetaldehyde and its identity was confirmed by mass spectral analysis. The formation of O-hydroxyphenylacetaldehyde from coumarin was NADPH-dependent. It was the major metabolite formed by rat, gerbil and human liver microsomes at a coumarin concentration of 1mM.
Experience has shown that the outcome of large and expensive validation studies on alternative me... more Experience has shown that the outcome of large and expensive validation studies on alternative methods can be compromised if their managers do not insist that optimised test protocols and proof of their performance are submitted before the start of the formal validation study. One way for the sponsors of validation studies to confirm both the likely relevance of a method for its stated purpose and its readiness for validation would be to require a prevalidation study before formal validation was contemplated. This process would involve the developers (or other proponents of the method) and selected independent laboratories in protocol refinement (Phase I) and protocol transfer (Phase II). The optimised protocol would then be assessed in a protocol performance phase (Phase III), which would involve the testing of a relevant set of coded test materials and an evaluation of a proposed prediction model. In certain circumstances, a successful outcome of Phase III might be sufficient for promotion of the regulatory acceptance of the method. Normally, however, the method would proceed to a formal validation study. The European Centre for the Validation of Alternative Methods, a recognised validation authority, now proposes to introduce this prevalidation scheme into its validation strategy.
This is the report of the twenty-second of a series of workshops organised by the European Centre... more This is the report of the twenty-second of a series of workshops organised by the European Centre for the Validation of Alternative Methods (ECVAM). ECVAM's main goal, as defined in 1993 by its Scientific Advisory Committee, is to promote the scientific and regulatory acceptance of alternative methods which are of importance to the biosciences and which reduce, refine or replace the use of laboratory animals. One of the first priorities set by ECVAM was the implementation of procedures which would enable it to become well-informed about the state-of-the-art of non-animal test development and validation, and the potential for the possible incorporation of alternative tests into regulatory procedures. It was decided that this would be best achieved by the organisation of ECVAM workshops on specific topics, at which small groups of invited experts would review the current status of various types of in vitro tests and their potential uses, and make recommendations about the best ways forward (1).
With regard to the problems encountered and the experience gained in validation studies conducted... more With regard to the problems encountered and the experience gained in validation studies conducted in the past, suggestions have been made concerning criteria for the selection of the tests and laboratories to be included in a validation study, the selection and distribution of test chemicals, and procedures for the handling, analysis and interpretation of the resulting data. In particular, tests
Toxicology in vitro : an international journal published in association with BIBRA, 1994
The use of in vitro techniques in toxicological research is widespread, but, up to now, relativel... more The use of in vitro techniques in toxicological research is widespread, but, up to now, relatively little progress has been made in applying the knowledge gained in regulatory toxicity testing. In vitro tests should be accepted into regulatory toxicology for at least five reasons: scientific, humanitarian, legislative, logistical and economic. In particular, in vitro tests have the potential to provide a mechanistic basis for toxicity testing, and they may permit the use of tissues from more-appropriate target species and individuals, including humans. The relevance and reliability of the in vitro test, with regard to its use for a particular purpose and with particular types of chemicals, should have been adequately demonstrated (i.e. it should have been validated) prior to regulatory acceptance. There are several obstacles to this, including whether validation should be based on comparisons between in vitro data and animal data, and whether the in vitro tests should be expected to...
This study compared five methods, the isolated rabbit eye (IRE), bovine corneal opacity and perme... more This study compared five methods, the isolated rabbit eye (IRE), bovine corneal opacity and permeability (BCOP), EpiOcular, fluorescein leakage (FL) and neutral red release (NRR) assays, for predicting the eye irritation potential of hair-care formulations. Ten shampoo and seven conditioner formulations of known ocular irritation potential were tested. Each group included a market-acceptable formulation as a comparative benchmark. Predictions of ocular irritation were made by using classification models (IRE, BCOP and EpiOcular assays) or by direct comparison with benchmarks (IRE, EpiOcular, FL and NRR assays). The BCOP assay was less sensitive than the IRE test in discriminating between formulations of different irritation potentials, and did not perform as well as the other assays in identifying mild formulations. All of the assays appeared to be better at discriminating correctly between the shampoos than between the conditioners. The EpiOcular assay showed the closest concordanc...
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