Latest Documents


  • 29-July-2016

    English

    Test No. 242: Potamopyrgus antipodarum Reproduction Test

    The Potamopyrgus antopodarumon reproduction test is designed to assess potential effects of prolonged exposure to chemicals on reproduction and survival of parthenogenetic lineages of the freshwater mudsnail Potamopyrgus antipodarum. Adult female P. antipodarum are exposed to a concentration range of the test chemical. The test chemical is dispersed into the reconstituted dilution water, added to test beakers, and adult snails are subsequently introduced into the test beakers. When testing “difficult chemicals” (i.e. volatile, unstable, readily biodegradable and adsorbing chemicals) the test can be conducted under flow-through conditions as an alternative to the semi-static design with fixed renewal periods of the medium (see paragraph 29). P. antipodarum survival over the 28 days exposure period and reproduction at the end of the test after 28 days are examined. Reproduction is evaluated by counting the number of embryo in the brood pouch (without distinction of developmental stages) at the end of 28 days exposure. The toxic effect of the test chemical on embryo numbers is expressed as ECX by fitting an appropriate regression model in order to estimate the concentration that would cause x % reduction in embryo numbers or alternatively as the No Observed Effect Concentration and Lowest Observed Effect Concentration (NOEC/LOEC) value (2).

  • 29-July-2016

    English

    Test No. 431: In vitro skin corrosion: reconstructed human epidermis (RHE) test method

    The test described in this Test Guideline allows the identification of corrosive chemical substances and mixtures and it enables the identification of non-corrosive substances and mixtures when supported by a weight of evidence determination using other existing information. The test protocol may also provide an indication of the distinction between severe and less severe skin corrosives. This Test Guideline does not require the use of live animals or animal tissue for the assessment of skin corrosivity.

    The test material (solid or liquid) is applied uniformly and topically to a three-dimensional human skin model, comprising at least a reconstructed epidermis with a functional stratum corneum. Two tissue replicates are used for each treatment (exposure time), and for controls. Corrosive materials are identified by their ability to produce a decrease in cell viability below defined threshold levels at specified exposure periods. Coloured chemicals can also be tested by used of an HPLC procedure. The principle of the human skin model assay is based on the hypothesis that corrosive chemicals are able to penetrate the stratum corneum by diffusion or erosion, and are cytotoxic to the underlying cell layers.

  • 29-July-2016

    English

    Test No. 421: Reproduction/Developmental Toxicity Screening Test

    This screening Test Guideline describes the effects of a test chemical on male and female reproductive performance. It has been updated with endocrine disruptor endpoints, in particular measure of anogenital distance and male nipple retention in pups and thyroid examination.

    The test substance is administered in graduated doses to several groups of males and females. Males should be dosed for a minimum of four weeks. Females should be dosed throughout the study, so approximately 63 days. Matings "one male to one female" should normally be used in this study. This Test Guideline is designed for use with the rat. It is recommended that each group be started with at least 10 animals of each sex. Generally, at least three test groups and a control group should be used. Dose levels may be based on information from acute toxicity tests or on results from repeated dose studies. The test substance is administered orally and daily. The results of this study include clinical observations, body weight and food/water consumption, oestrous cycle monitoring, offspring parameters observation/measurement, thyroid hormone measurement, as well as gross necropsy and histopathology. The findings of this toxicity study should be evaluated in terms of the observed effects, necropsy and microscopic findings. Because of the short period of treatment of the male, the histopathology of the testis and epididymus should be considered along with the fertility data, when assessing male reproductive effects.

  • 29-July-2016

    English

    Test No. 478: Rodent Dominant Lethal Test

    The purpose of the Dominant lethal (DL) test is to investigate whether chemical agents produce mutations resulting from chromosomal aberrations in germ cells. In addition, the dominant lethal test is relevant to assessing genotoxicity because, although they may vary among species, factors of in vivo metabolism, pharmacokinetics and DNA-repair processes are active and contribute to the response. Induction of a DL mutation after exposure to a test chemical indicates that the chemical has affected germinal tissue of the test animal.

    This modified version of the Test Guideline reflects more than thirty years of experience with this test and the potential for integrating or combining this test with other toxicity tests such as developmental, reproductive toxicity, or genotoxicity studies; however due to its limitations and the use of a large number of animals this assay is not intended for use as a primary method, but rather as a supplemental test method which can only be used when there is no alternative for regulatory requirements.

  • 29-July-2016

    English

    Test No. 243: Lymnaea stagnalis Reproduction Test

    This Test Guideline is designed to assess effects of prolonged exposure to chemicals on the reproduction and survival of the hermaphrodite freshwater snail Lymnaea stagnalis (the Great Pond Snail). Reproducing adults of L. stagnalis are exposed to a concentration range of the test chemical and monitored for 28 days for their survival and reproduction (number of egg clutches). As additional information, the number of eggs per clutch may also be determined. Adult shell length increase may also be measured. The toxic effect of the test chemical on the cumulated number of clutches produced per individual-day is expressed as ECx by fitting an appropriate regression model to the data in order to estimate the concentration that would cause x% reduction in the reproductive output. Alternatively, the toxic effect of the test chemical can be expressed as the No Observed Effect Concentration and Lowest Observed Effect Concentration (NOEC/LOEC) values. Both ECx and NOEC/LOEC can be determined from a single study.

  • 29-July-2016

    English

    Test No. 458: Stably Transfected Human Androgen Receptor Transcriptional Activation Assay for Detection of Androgenic Agonist and Antagonist Activity of Chemicals

    This Test Guideline describes an in vitro assay providing the methodology of Stably Transfected Transactivation to detect Androgen Receptor Agonists and Antagonists (AR STTA assays). The TA assay using a reporter gene technique is an in vitro tool that provides mechanistic data. The assay is used to establish signal activation or blocking of the androgen receptor caused by a ligand. Some chemicals may, in a cell type-dependent manner, display both agonist and antagonist activity and are known as selective androgen receptor modulators. Following the ligand binding, the receptor-ligand complex translocates to the nucleus where it binds specific DNA response elements and transactivates a firefly luciferase reporter gene, resulting in an increased cellular expression of the luciferase enzyme. Luciferin is a substrate that is transformed by the luciferase enzyme to a bioluminescence product that can be quantitatively measured with a luminometer. Luciferase activity can be evaluated quickly and inexpensively with a number of commercially available test kits. The test system provided in this Test Guideline utilises the AR-EcoScreenTM cell line.

  • 29-July-2016

    English

    Test No. 483: Mammalian Spermatogonial Chromosomal Aberration Test

    This test measures structural chromosomal aberrations (both chromosome- and chromatid-type) in dividing spermatogonial germ cells and is, therefore, expected to be predictive of induction of heritable mutations in these germ cells. The purpose of the in vivo mammalian spermatogonial chromosomal aberration test is to identify those chemicals that cause structural chromosomal aberrations in mammalian spermatogonial cells (1) (2) (3). In addition, this test is relevant to assessing genetoxicity because, although they may vary among species, factors of in vivo metabolism, pharmacokinetics and DNA-repair processes are active and contribute to the response.

    The original Test Guideline 483 was adopted in 1997. This modified version of the Test Guideline reflects many years of experience with this assay and the potential for integrating or combining this test with other toxicity or genotoxicity studies.

  • 29-July-2016

    English

    Test No. 422: Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test

    This screening Test Guideline describes the effects of a test chemical on male and female reproductive performance. It has been updated with endocrine disruptor endpoints, in particular measure of anogenital distance and male nipple retention in pups and thyroid examination.

    The test substance is administered in graduated doses to several groups of males and females. Males should be dosed for a minimum of four weeks. Females should be dosed throughout the study, so approximately 63 days. Matings "one male to one female" should normally be used in this study. This Test Guideline is designed for use with the rat. It is recommended that each group be started with at least 10 animals of each sex. Generally, at least three test groups and a control group should be used. Dose levels may be based on information from acute toxicity tests or on results from repeated dose studies. The test substance is administered orally and daily. The results of this study include clinical observations, body weight and food/water consumption, oestrous cycle monitoring, offspring parameters observation/measurement, thyroid hormone measurement, as well as gross necropsy and histopathology. The findings of this toxicity study should be evaluated in terms of the observed effects, necropsy and microscopic findings. Because of the short period of treatment of the male, the histopathology of the testis and epididymus should be considered along with the fertility data, when assessing male reproductive effects.

  • 29-July-2016

    English

    Test No. 226: Predatory mite (Hypoaspis (Geolaelaps) aculeifer) reproduction test in soil

    This Test Guideline describes a method to assess the effects of chemical substances in soil on the reproductive output of the soil mite species Hypoaspis (Geolaelaps) aculeifer Canestrini (Acari: Laelapidae). It can be used for water soluble or insoluble substances, but not with volatile substances.

    Adult females of similar age are exposed to a range of concentrations of the test substance mixed into 20 g dry mass of artificial soil 28-35 days after the start of the egg laying period. Depending on the endpoint (ECx, NOEC or both), five to twelve concentrations should be tested. At least two to four replicates for each test concentrations and six to eight control replicates, of 10 animals each, are recommended. At 20¡ãC, the test lasts 14 days after introducing the females, which usually allows the control offspring to reach the deutonymph stage. The number of surviving females (mortality ¡Ü 20% for a valid test) and the number of juveniles per test vessel (at least 50 for a valid test) are determined. The fecundity of the mites exposed to the test substance is compared to that of controls in order to determine the ECx (e.g. EC10, EC50) or the No Observed Effect Concentration (NOEC). Any observed differences between the behaviour and the morphology of the mites in the control and the treated vessels should be recorded.

  • 27-June-2016

    English

    Draft documents for public comments

    This page contains a list of the Guidelines for the Testing of Chemicals.

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