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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.
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).
This Test Guideline is designed for assessing the effects of chemicals on the reproduction of collembolans in soil. The parthenogenetic Folsomia candida is the recommended species for use, but an alternative species such as sexually reproducing Folsomia fimetaria could also be used if they meet the validity criteria. This Guideline can be used for testing both water soluble and insoluble substances but it is not applicable to volatile ones. The Guideline aims to determine toxic effects of the test substance on adult mortality and reproductive output expressed as LCx and ECx respectively, or NOEC/LOEC value. The number of treatment concentrations varies depending on endpoints to be determined. For a combined approach to examine both the NOEC/LOEC and ECx, eight concentrations in a geometric series with four replicates for each concentration as well as eight control replicates should be used. In each test vessel, 10 juveniles F. candida (or 10 males and 10 females adults F. fimetaria) should be placed on 30 g of modified OECD artificial soil using a 5 % organic matter content. The duration of a definitive reproduction test is 4 weeks for F. candida or 3 weeks for F. fimetaria.
This Test Guideline describes a method to estimate the developmental toxicity of a test chemical to the dung dwelling life stages of dung-dependent dipteran species. Two test species can be used. The test chemical is mixed with bovine faeces, to which either 10 eggs of Scathophaga stercoraria or 10 larvae of Musca autumnalis are added. The test will be terminated 5 days after emergence of the last adult in the control (> 18 days for S. stercoraria, >13 days for M. autumnalis). Then the possible impacts of the test chemical on the following measurement endpoints are assessed under controlled conditions: sex and total number of emerged adult flies, retardation of emergence indicated by the developmental rate and morphological change. Depending on the experimental design, the No Observed Effect Concentration (NOEC) or the Effect concentration for x percent effect (ECx) can be determined. This Guideline can be used for water soluble or insoluble substances, but is not applicable to volatile substances. If the toxicity of the chemical is unknown, five nominal test concentrations should be conducted. A positive control should be tested periodically. The test is considered valid if in the controls hatching of larvae is superior or equal to 70% of the number of introduced eggs, emergence of adults is superior or equal to 70% and superior or equal to 50% of the respectively hatched and introduced larvae and if the emergence of adult flies starts after 18 +- 2 days (S. stercoraria) or after 13 +- 2 days(M. autumnalis).
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.
This Test Guideline describes procedures designed to estimate the acute oral toxicity of substances to birds, and it provides three testing options: (1) limit dose test, (2) LD50-slope test, and (3) LD50-only test. The LD50-slope and LD50-only options are sequential testing procedures. The test method selected will depend on whether or not a definitive median dose (LD50) and slope of the dose-response curve are both needed. The limit dose test is the preferred test when toxicity is expected to be low and lethality is unlikely at the limit dose. The limit dose should be adequate for assessment purposes, and it is usually 2000 mg/kg-bwt. Five or ten birds are tested at the limit dose in addition to a control group. The LD50-slope test is the preferred test when regulatory or other requirements determine that the slope of the dose-response curve and/or the confidence interval is required in addition to an estimate of the LD50. This is a 3- or 4-stage test with 24 or 34 birds in addition to a control group. The LD50-only test is the preferred test when regulatory or other requirements determine that only the median lethal dose is required but neither the slope of the dose response curve or the confidence interval for the LD50 is required. This may be the appropriate test to estimate a percentile of a species sensitivity distribution of LD50s and to provide information for product labelling purposes. This test has two stages, with 14 birds in addition to a control group.
Software to be used with TG 223. Click here. Software not part of the Mutual Acceptance of Data.
This Test Guideline is designed to be used for assessing the effects of chemicals in soil on the reproductive output (and other sub-lethal end points) of the earthworm species Eisenia fetida or Eisenia andrei.
Adult worms are exposed to a range of concentrations of the test substance either mixed into the soil or applied to the soil surface. The range of test concentrations is selected to encompass those likely to cause both sub-lethal and lethal effects over a period of eight weeks. The limit test corresponds to one dose level of 1000 mg/kg. This study includes the observation of unusual behaviour and morphology, the counting and weighing of the adult worms after the four primary weeks, the number of juveniles hatched at the end of the second 4-week period. The reproductive output of the worms exposed to the test substance is compared to that of the control(s) in order to determine the no observed effect concentration (NOEC) and/or ECx by using a regression model to estimate the concentration that would cause a x % reduction in reproductive output. The test concentrations should bracket the ECx so that the ECx then comes from interpolation rather than extrapolation.
This Test Guideline is designed to be used for assessing the effects of chemicals on the reproductive output of the enchytraeid worm, Enchytraeus albidus Henle 1873, in soil.
Adult enchytraeid worms are exposed to a range of concentrations of the test substance mixed into an artificial soil. Ten worms are randomly allocated to each test vessel. A range-finding test should be used, for two weeks, in case of no sufficient information. The duration of the definitive test is six weeks. At the end the total number of juveniles produced by parent animal and the survival of parent animals are assessed. The limit test corresponds to one dose level of 1000 mg/kg. The study report should include the adult morphological changes, the number of offspring. The reproductive output of the animals exposed to the test substance is compared to that of the control(s) in order to determine the no observed effect concentration (NOEC) and/or ECx by using a regression model to estimate the concentration that would cause a x % reduction in reproductive output. The test concentrations should bracket the ECx so that the ECx then comes from interpolation rather than extrapolation.
Every three years, the Programme for International Student Assessment, better known as PISA, evaluates 15 year-old students around the world to determine how well their education system has prepared them for life after compulsory schooling. Once the results are published, the media rush to compare their countries’ positions in the international league tables. Government policy makers, journalists and academic researchers mine the report to find out how successful education systems elicit the best performance from their students while making access to high-quality education more equitable. But sometimes the key messages don’t make it back to the teachers who are preparing their country’s students every day.
Ten Questions for Mathematics Teachers… and How PISA Can Help Answer Them aims to change that. This report delves into topics such as, “How much should I encourage my students to be responsible for their own learning in mathematics?” or “As a mathematics teacher, how important is the relationship I have with my students?”. It gives teachers timely and relevant data and analyses that can help them reflect on their teaching strategies and how students learn.
Accelerating energy technology innovation is crucial to meet energy and climate goals, to support economic growth and to enhance energy security. Successful development and deployment of innovative energy technologies requires that stakeholders from both the public and private sector share knowledge, work collaboratively and, where appropriate, pool resources to deliver integrated, cost effective solutions to common challenges.
Four decades ago, the founders of the IEA had the foresight to create a multilateral technology collaboration mechanism – the IEA Implementing Agreements (IAs) – that has withstood the test of time and today is more relevant than ever to delivering solutions to global energy challenges. This network of experts produced a range of noteworthy results, including inventions, pilot plants, demonstration projects, databases and development of standards. The year 2015 marked the 40th anniversary of the mechanism as well as the rebranding of the IAs as Technology Collaboration Programmes (TCPs).
This publication provides an overview of the activities and recent accomplishments of TCPs. The 39 TCPs operating today involve about 6 000 experts from government, industry and research organisations in 51 countries around the world. Participants in TCPs have examined more than 1 900 energy-related topics in the areas of energy efficiency, renewable energy, fossil fuels, fusion power and cross-cutting issues.
The unrivalled breadth and coverage of analytical expertise seen in TCPs are unique assets that will underpin for the years to come IEA efforts to support innovation for energy security, economic growth and environmental protection.
This report looks at effective e-service provision by tax administrations, summarising eight critical areas, and explores big data management and portals, as well as natural systems, in detail. It highlights key opportunities in these areas, looking at how these emerging technologies can be best used by tax administrations. It also provides practical examples of how tax administrations have begun to utilise these technologies and delivers a maturity matrix for the two areas to assist strategic and operational decision making by tax administrations. Finally, it sets out conclusions, recommendations and next steps.
This report has been prepared by the Forum on Tax Administration’s E-services and Digital Delivery Programme. The work was initiated by the FTA Bureau as part of its 2015/16 work programme and was led by the Federal Tax Service of Russia (FTS). With tax administrations clear that e-service options can improve taxpayer compliance levels and participation while at the same time lowering their cost of operation; but with available options many and varied, and with the cost of implementation high, the FTA has over the last five years provided a wide range of guidance in the deployment of effective e-services.
If the quality of an education system can never exceed the quality of its teachers, then countries need to do all they can to build a high-quality teaching force. Teaching Excellence through Professional Learning and Policy Reform: Lessons from around the World, the background report to the sixth International Summit on the Teaching Profession, describes the knowledge, skills and character qualities common to the most effective teachers. It examines the education policies and practices that help teachers to acquire these tools, including through induction and mentoring programmes, ongoing professional development activities, student assessments, and collaboration with colleagues. The publication also discusses the importance of involving all stakeholders – especially teachers – in the process of education reform.
This new high profile report provides details of taxes paid on wages in twenty economies in Latin America and the Caribbean. It covers: personal income taxes and social security contributions paid by employees; social security contributions and payroll taxes paid by employers; cash benefits received by in-work families.
It illustrates how these taxes and benefits are calculated in each member country and examines how they impact on household incomes. The results also enable quantitative cross-country comparisons of labour cost levels and the overall tax and benefit position of single persons and families on different levels of earnings.
The publication shows the amounts of taxes and social security contributions levied and cash benefits received for eight different family types which vary by a combination of household composition and household type. It also presents the resulting average and marginal tax rates (i.e. the tax burden). Average tax rates show that part of gross wage earnings or total labour costs which is taken in tax and social security contributions (both before and after cash benefits). Marginal tax rates show the part of a small increase of gross earnings or total labour costs that is paid in these levies.
The data presented can be used in academic research and to analyse tax, social and economic policies in Latin America and the Caribbean.
This annual flagship publication provides details of taxes paid on wages in OECD countries. It covers: personal income taxes and employee contributions paid by employees, social security contributions and payroll taxes paid by employers, and cash benefits received by in-work families. It illustrates how these taxes and benefits are calculated in each member country and examines how they have an impact on household incomes. The results also enable quantitative cross-country comparisons of labour cost levels and the overall tax and benefit position of single persons and families on different levels of earnings.
The publication shows the amounts of taxes and social security contributions levied and cash benefits received for eight different family types, which vary by a combination of household composition and household type. It also presents: the resulting average and marginal tax rates (that is, the tax burden); the average tax rates (showing the part of gross wage earnings or total labour costs taken in tax and social security contributions, both before and after cash benefits); and the marginal tax rates (showing the part of a small increase of gross earnings or total labour costs that is paid in these levies).
This is the first edition of "Tax Policy Reforms in the OECD". This annual series of reports aims to track and compare tax policy developments over time across OECD countries. This year’s edition focuses on the tax reforms that were introduced in 2015 and identifies the most significant tax policy reforms as well as common tax policy trends across groups of countries. The Report is primarily based on responses to the OECD Tax Policy Reform Questionnaire which is sent yearly to all member countries to collect information on tax reforms and their expected revenue effects. Monitoring tax policy reforms across the OECD and understanding the context in which they were undertaken is crucial to inform tax policy discussions but also to support member and non-member countries in their assessment and design of future tax reforms.
Effective tax systems are a critical building block for increased domestic resources in developing countries, essential for sustainable development and for promoting self-reliance, good governance, growth and stability. This report begins with an overview of the current tax capacity building landscape, highlighting key initiatives and recent developments that have emerged in response to developing country needs. It then examines how tax administrations, as well as international and regional organisations, are supporting and delivering capacity building assistance to developing countries, and it offers guidance both in relation to G20 priorities and more generally. The report is based on a mapping exercise and a survey of members of the OECD’s Forum on Tax Administration (FTA), drawing on the insights and expertise of a nine-country task team led by the FTA commissioners of Canada and China and supported by the FTA Secretariat.
This report assesses the Republic of Kazakhstan’s significant efforts to improve water supply and sanitation (WSS) services over the past 15 years, notably in terms of ambitious target-setting, implementation of a sound water tariff policy, and significant investment in the rehabilitation and development of relevant infrastructure. Generally speaking, the absence of updated data on WSS institutional development is a limiting factor for further policy and programme development in the field, including in Kazakhstan. The monitoring and evaluation system proposed in this report aims to help assess progress in the WSS sector and serve as a basis for any necessary corrective measures.
This report maps the activities of ten leading Supreme Audit Institutions (SAIs) in Brazil, Canada, Chile, France, Korea, the Netherlands, Poland, Portugal, South Africa and the United States. In particular, it looks at how these SAIs assess key stages of the policy cycle as well as resulting policies and programmes. SAIs have untapped potential to go beyond their traditional oversight role and contribute evidence for more informed policy-making. The report provides examples and case studies of SAIs’ activities that consider and support the integration of international good practices into policy and programme formulation, implementation and evaluation. It provides guidance for SAIs seeking to engage in oversight, insight and foresight, taking into account the SAI’s internal strategy as well as policy challenges and actors in the external environment.
This report examines the nature and extent of support for teacher professionalism using the Teaching and Learning International Survey (TALIS) 2013, a survey of teachers and principals in 34 countries and economies around the world. Teacher professionalism is defined as the knowledge, skills, and practices that teachers must have in order to be effective educators.
The report focuses on lower secondary teachers (ISCED 2) in different education systems and looks at cross-cultural differences in teacher professionalism. It explores how teacher professionalism is linked to policy-relevant teacher outcomes such as perceived status, satisfaction with profession and school environment or perceived self-efficacy. The publication also tackles equity concerns in teacher professionalism: it examines professionalism support gaps, which are defined as differences in support for teacher professionalism in schools with high levels of disadvantage as compared to those with low-levels of disadvantage. Last but not least, the report presents a number of policy-relevant recommendations to enhance teacher professionalism and equity in access to high-quality teaching in OECD member countries.
The MENA region registered relatively dynamic economic growth and investment rates during the first decade of the century, even during the global economic and financial crisis. This was helped by important reforms by many governments to increase economic openness, diversification, private sector development and institutional reform. The participation of Tunisia and Jordan in the Open Government Partnership, the massive investment in infrastructure by Morocco and Egypt to increase connectivity and improve participation in global trade, and the efforts of the United Arab Emirates to diversify its economy demonstrate the great potential of the region to achieve progress. However, recent political instability and security threats have considerably slowed economic prospects. Reforms have not succeeded in tackling deeper structural challenges, such as corruption, unemployment, uneven development and unequal opportunities, especially for disadvantaged regions, women and youth. Appropriate policy responses are needed to regain stability and lay the foundations for a more open economy and a more inclusive development model. While the MENA region is profoundly heterogeneous, there are significant common economic and institutional trends that support the need for more concerted action to exploit the immense potential of the region and ensure its fruitful integration into the global economy.