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The purpose of the unscheduled DNA synthesis (UDS) test with mammalian liver cells in vivo is to identify substances that induce DNA repair after excision and removal of a stretch of DNA containing a region of damage induced by chemical substances (solid or liquid) or physical agents in the liver.
The test is usually based on the incorporation of tritium-labelled thymidine, 3H-TdR, (during 3-8 hours) into the DNA of liver cells which have a low frequency of cells in the S-phase of the cell cycle. The uptake of 3H-TdR is usually determined by autoradiography. Rats are commonly used, and the number of animals should be at least three analysable animals per group. Normally, at least two dose levels are used. A limit test may be performed if no effects would be expected at a dose of 2000 mg/kg bw/d. Test substances are generally administered as a single treatment by gavage using a stomach tube or a suitable intubation cannula. Liver cells are prepared from treated animals 12-16 hours after dosing of animal. After autoradiography, normally 100 cells are scored from each animal from at least two slides. A positive result from the UDS test with mammalian liver cells in vivo indicates that a substance induces DNA damage in mammalian liver cells in vivo that can be repaired by unscheduled DNA synthesis in vitro. A negative result indicates that, under the test conditions, the test substance does not induce DNA damage that is detectable by this test.
This book shows hows how regulatory reform has produced substantial economic and social benefits for citizens by enhancing competition and reducing regulatory costs. It can boost efficiency, sharply reduce prices, stimulate innovation, and improve the ability of economies to adapt to change and remain competitive in global markets. Properly done, regulatory reform also can help governments promote other important policy goals, such as environmental quality, health, and safety. Finally, country experience shows that disruptions which can accompany reform can be addressed by complementary policies and actions. In this Report, the OECD calls for renewed attention to regulatory reform, and the recommendations in this Report constitute an ambitious plan for action. In May 1997, Ministers of OECD countries welcomed this Report and agreed to work to implement its recommendations in their countries.
Energy use patterns and trends are shaped by the decisions of hundreds of millions of individuals, households, and organisations. Understanding this complex fabric of energy use, and the consequent carbon dioxide emissions, is vital to developing effective policies in support of energy security, economic prosperity, and environmental protection. This book illustrates how indicators can extract from that fabric the most important links among energy uses, behaviour, the economy, and government policy. It explains how energy use has evolved in the past and what is influencing it now, and provides insights on what could shape it in the future. This represents an important step in better understanding the link between energy use and human activity.
The agro-food sector in OECD countries is heading towards an era of turbulance and transition. With food demand in developing countries growing, barriers to trade and investment falling, and consumer tastes and preferences rapidly diversifying, the landscape of OECD food markets will be radically different 20 years from now. Are food shortages likely and what will happen to food prices? What changes will we see in food retailing and food processing? Will there be more co-operation between the various players in the agro-food industry, more concentration or more competition? To grasp these challenges, this report looks into the prospects for the agro-food sector to 2010-20 and examines the new generation of key issues that lie ahead for governments, business, farmers and consumers.
This book examines the performance of social assistance policies in four countries with similar per capita incomes: Australia, Finland, Sweden and the United Kingdom. It confronts their -- very different -- social protection systems and sheds light on issues such as social insurance and social assistance, central and local social security systems, active and passive policies. The often complex interactions involved are analysed and lessons are drawn from the countries' varied experiences. Particular attention is paid to young people, the long-term unemployed, lone-parent families, immigrants and asylum seekers. Conclusions -- both country-based and thematic -- are presented with a particular emphasis on how barriers and disincentives to employment can be overcome: these are indispensable weapons in the battle against exclusion.
This annual publication provides unique information on direct taxes levied from employees and their employers in all OECD countries. In addition, the book specifies family benefits paid as cash transfers. Amounts of taxes and benefits are detailed program by program, for eight households types, which differ by income level and household composition. Results include the tax burden for one- and two- earner families.
Tax sparing provisions have now more than four decades of history in bilateral tax treaties, including treaties between OECD countries. But the world of today is quite different from that when the positions of OECD Member and non-member countries towards tax sparing were developed. These changes in the international setting have led countries to reconsider their attitude towards tax sparing and the design of such provisions. This report examines the practices of Member countries and explains why Member countries have become more reluctant to grant tax sparing in treaties. It also provides a number of suggested "best practices" on the design of tax sparing provisions in tax treaties.
OECD countries have started to reform their agricultural policies in the last decade. Many countries have also implemented agri-environmental measures that are directly aimed at improving the environment.
What are the changes in land use, farming practices and input use resulting from these reforms? What have been the effects on the environment: soils, water, air, biodiversity, wildlife habitat and landscape? How have regional and local conditions influenced the environmental outcomes? To what extent have agri-environmental measures contributed to achieving sustainable agriculture? And how could such measures be made more effective and cost-efficient?
Through examining concrete policy experiences from OECD countries, this study concludes that agricultural policy reforms can improve the environment, provided they are accompanied by appropriate environmental measures.
Technological change and financial deregulation have dramatically globalised financial markets. Financial firms have developed innovative financial instruments, such as swaps and derivatives, to meet the often different global demand of investors and borrowers and have organised themselves to sell such global financial products 24 hours a day. This phenomenon of global trading challenges tax payers and tax administrations to come up with a fair way of allocating and taxing the profits in each country where global trading is carried on.
This publication thoroughly reviews the factual background to global trading, analyses the challenges posed to traditional taxation methods and discusses a range of policy options to tackle the problems. Although the paper discusses a specific industry sector, many of the issues raised, for example the high level of global integration of functions and intensive co-operation between different geographic locations, are becoming more common in other industries with the spread of globalisation and the communications revolution.
Based on scenarios produced by the Asian Development Bank (ADB) and the OECD Development Centre, the authors consider ways in which long-term Asian growth can be consolidated to the benefit of the global economy as a whole. Looking beyond current economic difficulties, Asian countries have strong growth prospects, assuming they pay due attention to domestic institutional strengthening, investment in human capital and the conservation of environmental capital.
This volume was produced as a product of the third "International Forum on Asian Perspectives", organised annually by the ADB and the OECD Development Centre. The purpose of the Forum is to encourage interchange of ideas between Asian and European specialists on questions of economic importance to the two regions.
How has the situation in the transport sector - passenger and freight transport - changed? What about road safety? This publication gives the latest statistics on the situation of the transport market in Europe and presents charts which help show what changes have occurred between 1970 and 1996.
Because it is published earlier than any other comparable study, this report provides the reader with first-hand figures about transport trends. It presents both an analysis of the transport situation in Western Europe and a special study on recent transport trends in countries in transition.
Interest in sustainable development and awareness of the international dimension of environmental problems, have stimulated governments to track and chart environmental progress and its links with economic conditions and trends.
This publication presents leading environmental indicators from the OECD Core Set and thus contributes to measuring environmental performance and progress towards sustainable development.
Organised by issues such as climate change, air pollution, biodiversity, waste or water resources, this book provides essential information for all those interested in sustainable development.
While the development of new knowledge is becoming increasingly important in the emerging knowledge-based economy, the impact of technology on growth, jobs and welfare is determined largely by the way in which technology is diffused, absorbed and used throughout the economy. For technological progress to bring not only higher productivity but also economic expansion and new jobs it is pivotal with conditions which allow for industrial restructuring, entry and expansion of small firms, growth of new industries, launching of new products, and mechanisms accounting for effective upskilling of the labour force.
This report points to a decline in public support for research and development (R&D), mainly affecting basic, long-term research, and examines the levelling-off in private sector R&D along with changes in its direction away from basic, exploratory research towards more market-driven and short-term innovative efforts. It explores how the special characteristics of national innovation systems impact on the mechanisms for innovation and diffusion of technology, and examines the rationale for policy in this area. A key challenge for policy makers is to co-ordinate measures so as to obtain consistent and credible incentives for firms and individuals. Assessing what works and what does not work in policy, the report identifies "best practices" in specific areas: management of the science base; financial support for industrial R&D efforts; technology diffusion policies and initiatives; policies for new technology-based firms; policies for facilitating growth in new demand; and policies for high-performance workplaces and intangible investment.
Despite many initiatives, OECD countries have not yet fully adapted to the characteristics and challenges of knowledge-based economies. Technology policies continue to be too piecemeal, paying insufficient attention to linkages within national innovation systems and to broader structural reforms. They focus too much on the small high-tech segment of the economy and too little on fostering innovation and technology diffusion economy-wide. There is also scope for improving the effectiveness of policies, notably through increased use of market-based instruments and better evaluation. Recommendations are put forward of measures to be taken by individual OECD countries.
International trade has played a key role in the transition process. Exports were essential for the recovery from the transition shock and sustainable growth depends on the capacity of each country to reap the benefits of the openness to international trade and foreign investment. This book offers a comprehensive and a comparative approach on the different interactions between trade, FDI and the process of economic transformation. One of its original points is the quantification of both price and non-price aspects of product market competition. Based on this analysis, each country is ranked according to the type and strength of its competitive position and conclusions are drawn concerning further economic restructuring.
Transport networks in Europe are insufficiently integrated and subject to widespread and increasing congestion, particularly on the roads. This publication reviews these issues and, more specifically, examines the problem of providing better access to Western Europe for peripheral regions and for Central and Eastern Europe, as well as the need to upgrade networks.
Current responses to these problems are inadequate. Statistics and analytical tools are lacking, national approaches are highly differentiated, and analyses and concepts are rudimentary and overly sectoral.
This publication analyses, on an homogeneous basis, the inland transport infrastructures, the investment forecasts and the main traffic flows in 30 European countries of the ECMT. This comparative presentation may be considered as a first step towards better knowledge of the European background.
In this Short-term Toxicity Test on Fish Embryo and Sac-Fry Stages, the life stages from the newly fertilized egg to the end of the sac-fry stage are exposed.
The embryo and sac-fry stages of fish are exposed to five concentrations of the test substance dissolved in water. A choice, depending on the nature of the test substance, is possible between a semi-static and a flow-through procedure. The test starts with placing at least 30 fertilised eggs divided equally between at least three replicate test chambers per concentration, and is terminated just before the yolk-sac of any larvae in any of the test chambers has been completely absorbed or before mortalities by starvation start in controls. Lethal and sub-lethal effects are assessed and compared with control values to determine the lowest observed effect concentration and hence the no observed effect concentration. Alternatively, they may be analysed using a regression model in order to estimate the concentration that would cause a given percentage effect. The study report should include: the daily counting of the offspring, the daily recording of the parent mortality, the weekly measurement of oxygen concentration, temperature, and pH values; and the determination of the concentrations of test substance. It should also include the observations of abnormal appearance, abnormal behaviour, hatching and survival...
This Test Guideline is a laboratory test method, designed to assess the acute contact toxicity of pesticides and other chemicals to adult worker honeybees.
Anaesthetized adult worker honeybees are exposed to five doses in a geometric series of the test substance dissolved in appropriate carrier (in total a volume of 1 ml), by direct application to the thorax (droplets). A minimum of three replicate test groups, each of ten bees, should be dosed with each test concentration. A toxic standard (usually dimethoate) should be included in the test series. The limit test corresponds to one dose level of 100 ìg active ingredient/bee. The test duration is 48h. Mortality is recorded daily during at least 48 hours and compared with control values. If the mortality rate is increasing between 24 and 48h whilst control mortality remains at an accepted level, it is appropriate to extend the duration of the test to a maximum of 96h. The results are analysed in order to calculate the LD50 at 24h and 48h and, in case the study is prolonged, at 72h and 96h.
This Test Guideline is a laboratory test method, designed to assess the oral acute toxicity of pesticides and other chemicals, to adult worker honeybees.
Adult worker honeybees are exposed to five doses in a geometric series of the test substance dispersed in sucrose solution. A minimum of three replicate test groups, each of ten bees, should be dosed with each test concentration. A toxic standard (usually dimethoate) should be included in the test series. The bees are then fed the same diet, free of the test substance. The limit test corresponds to one dose level of 100 ìg active ingredient/bee. Mortality is recorded daily during at least 48 hours and compared with control values. If the mortality rate is increasing between 24 and 48h whilst control mortality remains at an accepted level it is appropriate to extend the duration of the test to a maximum of 96h. The study report should include the amount of diet consumed per group and the observation of all abnormal behavioural. The results are analysed in order to calculate the LD50 at 24h and 48h and, in case the study is prolonged, at 72h and 96h.