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Ecosystem accounting is a relatively new and emerging field dealing with integrating complex biophysical data, tracking changes in ecosystems and linking those changes to economic and other human activity. Considering the increasing demand for statistics on ecosystems within analytical and policy frameworks on environmental sustainability, human well-being and economic growth and development, there has been an increasing urgency to advance this emerging field of statistics.
Although considerable experience exists in related areas of statistics such as land cover and land use statistics, the integration of these and other information into an ecosystem accounting framework is new. Also, there is considerable existing expertise in the ecosystem sciences and economics fields that is relevant, and again it is the focussing of these different areas of expertise on the proposed ecosystem accounting approach that is new.
SEEA-Experimental Ecosystem Accounting provides a synthesis of the current knowledge in this area and provides a starting point for the development of ecosystem accounting at national and sub-national levels. It represents an important step forward on ecosystem accounting, providing a common set of terms, concepts, accounting principles and classifications; an integrated accounting structure of ecosystem services and ecosystem condition in both physical and monetary terms; and the recognition of spatial areas as forming the basic focus for measurement.

Southeast Asia’s booming economy offers tremendous growth potential, but also large and interlinked economic, social and environmental challenges. The region’s current growth model is based in large part on natural resource exploitation, exacerbating these challenges. This report provides evidence that, with the right policies and institutions, Southeast Asia can pursue green growth and thus sustain the natural capital and environmental services, including a stable climate, on which prosperity depends.

Carried out in consultation with officials and researchers from across the region, Towards Green Growth in Southeast Asia provides a framework for regional leaders to design their own solutions to move their countries towards green growth. While recognising the pressures that Southeast Asian economies face to increase growth, fight poverty and enhance well-being, the report acknowledges the links between all these dimensions and underscores the window of opportunity that the region has now to sustain its wealth of natural resources, lock-in resource-efficient and resilient infrastructure, attract investment, and create employment in the increasingly dynamic and competitive sectors of green technology and renewable energy.

Some key policy recommendations are that these challenges can be met by scaling up existing attempts to strengthen governance and reform countries’ economic structure; mainstreaming green growth into national development plans and government processes; accounting for the essential ecosystem services provided by natural capital, ending open-access natural resource exploitation; and guiding the sustainable growth of cities to ensure well-being and prosperity.

Ce rapport s’appuie sur les travaux de l’OCDE dans les domaines de la gouvernance de l’eau, de la politique de la réglementation et de la participation du secteur privé pour identifier les défis de gouvernance à la mobilisation des partenariats public-privé (PPP) dans la gestion des services de l’eau et de l’assainissement en Tunisie, et suggérer des recommandations de politiques publiques pour les surmonter.

Il s’inscrit dans le cadre du dialogue sur les politiques conduit conjointement par l’OCDE et le Global Water Partnership-Mediterranean (GWP-Med) dans le cadre du projet labellisé par l’Union pour la Méditerranée (UpM) « Gouvernance et Financement du Secteur de l’Eau en Méditerranée », avec le soutien financier du fonds fiduciaire FEMIP de la Banque Européenne d’Investissement.

An integral component of any green growth strategy is a highly-reliable set of measurement tools and indicators that would enable policy makers to evaluate how effective policies are, and to gauge the progress being achieved in shifting economic activity onto a greener path. These tools and indicators, which will need to be based on internationally comparable data, must also be embedded in a conceptual framework and selected according to a clearly-specified set of criteria.

This report is a first step towards developing a framework to monitor progress on green growth in the agricultural sector in OECD countries. The goal is to identify relevant, succinct and measurable statistics to implement the OECD Green Growth Strategy Measurement Framework which provides a common basis for further developing green growth indicators in the agricultural sector in OECD countries.

The mammalian in vivo chromosome aberration test is used for the detection of structural chromosome aberrations induced by test compounds in bone marrow cells of animals, usually rodents (rats, mice and Chinese hamsters). Structural chromosome aberrations may be of two types: chromosome or chromatid.

Animals are exposed to the test substance (liquid or solid) by an appropriate route of exposure (usually by gavage using a stomach tube or a suitable intubation cannula, or by intraperitoneal injection) and are sacrificed at appropriate times after treatment. Prior to sacrifice, animals are treated with a metaphase-arresting agent. Chromosome preparations are then made from the bone marrow cells and stained, and metaphase cells are analysed for chromosome aberrations. Each treated and control group must include at least 5 analysable animals per sex. The limit dose is 2000 mg/kg/body weight/day for treatment up to 14 days, and 1000 mg/kg/body weight/day for treatment longer than 14 days.

The mammalian in vivo micronucleus test is used for the detection of damage induced by the test substance to the chromosomes or the mitotic apparatus of erythroblasts, by analysis of erythrocytes as sampled in bone marrow and/or peripheral blood cells of animals, usually rodents (mice or rats).

The purpose of the micronucleus test is to identify substances (liquid or solid) that cause cytogenetic damage which results in the formation of micronuclei containing lagging chromosome fragments or whole chromosomes. An increase in the frequency of micronucleated polychromatic erythrocytes in treated animals is an indication of induced chromosome damage. Animals are exposed to the test substance by an appropriate route (usually by gavage using a stomach tube or a suitable intubation cannula, or by intraperitoneal injection). Bone marrow and/or blood cells are collected, prepared and stained. Preparations are analyzed for the presence of micronuclei. Each treated and control group must include at least 5 analysable animals per sex. Administration of the treatments consists of a single dose of test substance or two daily doses (or more). The limit dose is 2000 mg/kg/body weight/day for treatment up to 14 days, and 1000 mg/kg/body weight/day for treatment longer than 14 days.

The in vivo alkaline single cell gel electrophoresis assay, also called alkaline Comet Assay is a method measuring DNA strand breaks in eukaryotic cells.

Each treated group is composed of a minimum of 5 animals of one sex (or of each sex as appropriate). A positive and a vehicle control group are also used. Administration of the treatment consists of daily doses over duration of 2 days or more, ensuring the test chemical reaches the target tissue which can be the liver, the kidney or other tissues if justified.

Tissues of interest are dissected and single cells/nuclei suspensions are prepared and embedded in agarose on slides. Cells/nuclei are treated with lysis buffer to remove cellular and/or nuclear membranes. The nuclear DNA in the agar is then subjected to electrophoresis at high pH. This results in structures resembling comets which by using suitable fluorescent stain, can be observed by fluorescent microscopy. Based on their size DNA fragments migrate away from the head to the tail, and the intensity of the comet tail relative to the total intensity (head plus tail) reflects the amount of DNA breakage.

Le but de l'essai in vitro d'aberration chromosomique est d'identifier les agents qui causent des aberrations chromosomiques structurales dans les cellules mammifères cultivées. Les aberrations structurales peuvent être de deux types : chromosomiques ou chromatidiques.

L'essai in vitro d'aberration chromosomique peut utiliser des cultures de lignées cellulaires établies, des souches cellulaires ou des cultures de cellules primaires. Des cultures cellulaires sont exposées à la substance d'essai (liquide ou solide) avec et sans activation métabolique pendant environ 1.5 fois le cycle cellulaire normal. Au moins trois concentrations analysables de la substance d'essai devraient être employées. Il faut normalement réaliser les cultures en doublon à chaque niveau de dose. À intervalles prédéterminés après exposition des cultures de cellules à la substance d'essai, les cellules sont traitées avec une substance qui bloque la métaphase, récoltées et teintées. Les cellules métaphasiques sont analysées au microscope pour déceler les aberrations chromosomiques.

The present Test Guideline addresses the human health hazard endpoint skin corrosion, following exposure to a test chemical. Skin corrosion is defined as the production of irreversible tissue damage, manifested as visible necrosis of the skin, according to the definition of the Globally Harmonised System for Classification and Labeling of Chemicals.

This Test Guideline describes an in vitro procedure allowing the identification of non-corrosive and corrosive substances and mixtures, based on three-dimensional human skin model which reliably reproduces histological, morphological, biochemical, and physiological properties of the upper layers of human skin, including a functional stratum corneum. The procedure on reconstituted human epidermis is based on the principle that corrosive chemicals are able to penetrate the stratum corneum by diffusion or erosion, and are cytotoxic to the underlying cell layers. Two tissue replicates are used for each treatment (or 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 time. 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. Corrosive substances are evidenced by their capacity to reduce cell viability below the defined threshold.

Several validated methods are referenced in the Test Guideline and follow the procedure described above. Some of the methods referenced allow sub-categorisation among corrosive chemicals.

This Test Guideline also includes a set of Performance Standards (PS) for the assessment of similar and modified TER-based test methods.

L’essai in vivo d’électrophorèse sur gel en conditions alcalines de cellules isolées, aussi appelé test des comètes est une méthode mesurant les cassures de brins d’ADN dans les cellules eucaryotes.

Chaque groupe traité est composé au minimum de 5 animaux d’un même sexe (ou de chaque sexe si besoin est). On utilise également un groupe témoin positif et un groupe témoin négatif. Les animaux reçoivent un traitement quotidien sur une durée de 2 jours ou plus, permettant au produit chimique d’essai d’atteindre le tissu cible, celui-ci peut être le foie, le rein, ou tous autres tissus si cela est justifié.

Les tissus à étudier sont disséqués et des suspensions de cellules/noyaux isolés sont préparées, puis incluses dans un gel d’Agarose pour être fixé sur des lames. Les cellules/noyaux sont traitées avec un tampon de lyse pour éliminer la membrane cellulaire et/ou nucléaire. L’ADN nucléaire dans l’agar est ensuite soumis à une électrophorèse à pH élevé produisant des structures ressemblant à des comètes qui, si l’on utilise les colorants fluorescents appropriés, peuvent être observées par microscopie à fluorescence. En fonction de leur taille les fragments d’ADN migrent de la tête vers la queue de la comète, et l’intensité de la queue de la comète relative à l’intensité totale (tête plus queue) reflète l’ampleur des cassures de l’ADN.

La présente Ligne directrice porte sur le danger de corrosion cutanée pour la santé humaine faisant suite à une exposition avec un produit chimique. La corrosion cutanée désigne la survenue de lésions irréversibles de la peau qui se manifestent par une nécrose visible, selon la définition du Système Général Harmonisé pour la Classification et l’Étiquetage des produits chimiques.

Cette Ligne directrice décrit une procédure in vitro permettant d’identifier les substances et mélanges corrosifs et non corrosifs, en faisant appel à un épiderme humain reconstitué qui reproduit fidèlement les propriétés histologiques, morphologiques, biochimiques et physiologiques des couches supérieures de la peau humaine. La procédure sur épiderme humain reconstitué part du principe que les substances corrosives sont capables de pénétrer dans le stratum corneum (couche cornée) par diffusion ou érosion, et sont cytotoxiques pour les cellules des couches sous-jacentes. Deux réplicats sont employés pour chaque traitement (ou durée d'exposition), et pour les contrôles. Les substances corrosives sont identifiées sur la base de leur capacité à réduire la viabilité cellulaire en dessous des valeurs seuils définies pour des périodes d'exposition spécifiques. La viabilité cellulaire est mesurée via la conversion enzymatique du colorant vital MTT en un sel de formazan bleu mesuré quantitativement après son extraction des tissus. Les substances corrosives sont mises en évidence par leur capacité à faire chuter la viabilité cellulaire sous un seuil prédéterminé.

Plusieurs méthodes validées sont référencées dans la Ligne directrice et suivent la procédure décrite ci-dessus. Certaines méthodes référencées permettent par aillaurs la sous-categorisation des produits corrosifs.

Cette Ligne directrice comprend également un ensemble de normes de performances pour l’évaluation de méthodes d’essai similaires ou modifiées.