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This Test Guideline describes an in vitro procedure that may be used for the hazard identification of irritant chemicals (substances and mixtures) in accordance with the UN Globally Harmonized System of Classification and Labelling (GHS) Category 2.  It is based on reconstructed human epidermis (RhE), which in its overall design closely mimics the biochemical and physiological properties of the upper parts of the human skin. Cell viability is measured by enzymatic conversion of the vital dye MTT into a blue formazan salt that is quantitatively measured after extraction from tissues. Irritant test substances are identified by their ability to decrease cell viability below defined threshold levels (below or equal to 50% for UN GHS Category 2). Coloured chemicals can also be tested by used of an HPLC procedure. There are three validated test methods that adhere to this Test Guideline. Depending on the regulatory framework and the classification system in use, this procedure may be used to determine the skin irritancy of test substances as a stand-alone replacement test for in vivo skin irritation testing, or as a partial replacement test, within a tiered testing strategy.

This method provides information on health hazard likely to arise from exposure to liquid or solid test substance by dermal application. This Test Guideline recommends sequential testing strategies, which include the performance of validated and accepted in vitro or ex vivo tests for corrosion/irritation.

The albino rabbit is the preferable laboratory animal. The substance to be tested is applied in a single dose to a small area of skin (approximately 6cm²) of an experimental animal; untreated skin areas of the test animal serve as the control. The exposure period is 4 hours. Residual test substance should then be removed. The dose is 0.5ml (liquid) or 0.5g (solid) applied to the test site. The method consists of two tests: the initial test and the confirmatory test (used only if a corrosive effect is not observed in the initial test). All animals should be examined for signs of erythema and oedema during 14 days. The dermal irritation scores should be evaluated in conjunction with the nature and severity of lesions, and their reversibility or lack of reversibility. When responses persist to the end of the 14-day observation period, the test substance should be considered an irritant.

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.

The in vitro mammalian cell gene mutation test can be used to detect gene mutations induced by chemical substances. This TG includes two distinct in vitro mammalian gene mutation assays requiring two specific tk heterozygous cells lines: L5178Y tk+/-3.7.2C cells for the mouse lymphoma assay (MLA) and TK6 tk+/- cells for the TK6 assay. Genetic events detected using the tk locus include both gene mutations and chromosomal events.Cells in suspension or monolayer culture are exposed to, at least four analysable concentrations of the test substance, both with and without metabolic activation, for a suitable period of time. They are subcultured to determine cytotoxicity and to allow phenotypic expression prior to mutant selection. Cytotoxicity is usually determined by measuring the relative cloning efficiency (survival) or relative total growth of the cultures after the treatment period. The treated cultures are maintained in growth medium for a sufficient period of time, characteristic of each selected locus and cell type, to allow near-optimal phenotypic expression of induced mutations. Mutant frequency is determined by seeding known numbers of cells in medium containing the selective agent to detect mutant cells, and in medium without selective agent to determine the cloning efficiency (viability). After a suitable incubation time, colonies are counted.

The 2011 Green Growth Strategy provided initial guidance to governments on how to achieve economic growth and development, while preventing costly environmental damage and inefficient resource use. What progress have countries made in aligning economic and environmental priorities since 2011? This report attempts to evaluate this progress and highlight where there is broad scope to heighten the ambition and effectiveness of green growth policy. It draws lessons from green growth mainstreaming across the OECD’s work programme, notably in terms of how governments can maximise institutional settings to seize economic opportunities surrounding the transition to a green economy, and considers ways to enrich the Green Growth Strategy based on work undertaken since its launch.

Agriculture and the agro-processing sector in Brazil have shown impressive growth over the past two decades. This has largely been driven by productivity improvements and structural adjustment resulting from broad economic reforms, as well as new technologies developed by agricultural science. Government policy and industry initiatives are increasingly focused on the sustainability of agricultural development.

Climate change is giving rise to diverse risks, ranging from changing incidences of tropical diseases to increased risks of drought, varying widely in their potential severity, frequency and predictability. Governments must integrate the management of these climate risks into policy making if they are to successfully adapt to a changing climate. Economic analysis has a vital role to play in supporting these efforts, by identifying costs and benefits and supporting decision-making for an uncertain future. However, this analysis needs to be adapted to the institutions, policies and climate risks in a given country. Building on the experience of OECD countries, this report sets out how the latest economic evidence and tools can enable better policy making for adaptation.