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Over 100 million workers in Southeast Asia have jobs that are directly or closely linked to the environment, making them vulnerable to climate change impacts. These same workers likely earn at least 20% lower than the national average and are largely in informal employment. The region’s necessary transition towards greener growth could affect them in several ways: some sectors will create jobs and others will lose jobs or disappear altogether. Understanding the effects of both climate change and green growth policies on jobs and people is thus essential for making the transition in Southeast Asia an inclusive one. The study explores these issues, with emphasis on the potential effects on labour of an energy transition in Indonesia, and of a transition in the region’s agricultural sector, illustrated by a simulated conversion from conventional to organic rice farming.

The re-opening of Samoa’s borders in late-2022 kickstarted the country’s recovery from the COVID-19 pandemic. This offers an opportunity to rebuild sustainably its tourism, maritime transport, and fisheries sectors. Samoa’s ocean resources can also augment its resilience to future shocks such as climate change. Through an analysis of Samoa’s economic trends and environmental pressures, institutional set-up and policy tools, as well as financing landscape, this report identifies opportunities and challenges for Samoa’s ocean economy to drive sustainable and resilient development. The Samoa Ocean Strategy offers a blueprint for such a pursuit, but there remain gaps and impediments. To address them, the report provides several cross-cutting and sector-specific policy recommendations to accelerate Samoa’s transition to a sustainable ocean economy.

The Climate Action Monitor is a key publication of the International Programme for Action on Climate (IPAC). It provides a synthesis of climate action and progress towards net-zero targets for 51 OECD and OECD partner countries. This year's edition presents a summary of information on greenhouse gas emissions, an assessment of climate-related hazards and recent trends in climate action. Directed towards policymakers and practitioners, the findings suggest that without increased ambition and a significant expansion in national climate action, countries will not be able to meet the net-zero challenge.

This Test Guideline (TG) describes the IL-2 Luc Assay test method to evaluate the potential immunotoxic effects of chemicals on T lymphoblastic cell line. This cell line allows quantitative measurement of luciferase gene induction by detecting luminescence from well-established light producing luciferase substrates as indicators of the activity of IL-2, IFN-γ and GAPDH in cells following exposure to immunotoxic chemicals. The method is intended to be used as a part of a battery to determine immunotoxic potential of chemicals.

The in vitro micronucleus test is a genotoxicity test for the detection of micronuclei in the cytoplasm of interphase cells. Micronuclei may originate from acentric chromosome fragments (i.e. lacking a centromere), or whole chromosomes that are unable to migrate to the poles during the anaphase stage of cell division. The assay detects the activity of clastogenic and aneugenic test substances in cells that have undergone cell division during or after exposure to the test substance. This Test Guideline allows the use of protocols with and without the actin polymerisation inhibitor cytochalasin B. Cytochalasin B allows for the identification and selective analysis of micronucleus frequency in cells that have completed one mitosis, because such cells are binucleate. This Test Guideline also allows the use of protocols without cytokinesis block provided there is evidence that the cell population analysed has undergone mitosis.   

This Test Guideline describes in vitro assays, which use Androgen Receptor TransActivation (ARTA) to detect Androgen Receptor Agonists and Antagonists. The ARTA assay methods are mechanistically and functionally similar test methods that provide information on the transcription and translation of a reporter gene following the binding of a chemical to the androgen receptor and subsequent transactivation. The cell lines used in these assays express AR and have been stably transfected with an AR-responsive luciferase reporter gene, and are used to identify chemicals that activate (i.e. act as agonist) or inhibit (i.e. act as antagonists) AR-dependent transcription. Some chemicals may, in a cell type-dependent manner, display both agonist and antagonist activity and are known as selective AR modulators. The AR is activated following ligand binding, after which the receptor-ligand complex binds to specific DNA responsive elements and transactivates the receptor gene, resulting in an increase cellular expression of the luciferase enzyme. The enzyme then transforms the substrate to a bioluminescent product that can be quantitatively measured with a luminometer. This Test Guideline includes ARTA assays using the AR-EcoScreenTM cell line, the AR-CALUX® cell line, and 22Rv1/MMTV_GR-KO cell line.

The in vitro macromolecular test method is a biochemical in vitro test method that can be used to identify chemicals (substances and mixtures) that have the potential to induce serious eye damage as well as chemicals not requiring classification for eye irritation or serious eye damage. The in vitro macromolecular test method contains a macromolecular reagent composed of a mixture of proteins, glycoproteins, carbohydrates, lipids and low molecular weight components, that when rehydrated forms a complex macromolecular matrix which mimics the highly ordered structure of the transparent cornea. Corneal opacity is described as the most important driver for classification of eye hazard. Test chemicals producing protein denaturation, unfolding and changes in conformation will lead to the disruption and disaggregation of the highly organised macromolecular reagent matrix, and produce turbidity of the macromolecular reagent. Such phenomena is quantified, by measuring the changes in light scattering (at a wavelength of 405 nm using a spectrometer), which is compared to the standard curve established in parallel by measuring the increase in OD produced by a set of calibration substances.

The present Key Event based Test Guideline (TG) addresses the human health hazard endpoint skin sensitisation, following exposure to a test chemical. More specifically, it addresses the activation of dendritic cells, which is one Key Event on the Adverse Outcome Pathway (AOP) for Skin Sensitisation. Skin sensitisation refers to an allergic response following skin contact with the tested chemical, as defined by the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (UN GHS). This TG provides three in vitro test methods addressing the same Key Event on the AOP: (i) the human cell Line Activation Test or h-CLAT method, (ii) the U937 Cell Line Activation Test or U-SENS and (iii) the Interleukin-8 Reporter Gene Assay or IL-8 Luc assay. All of them are used for supporting the discrimination between skin sensitisers and non-sensitisers in accordance with the UN GHS. Test methods described in this TG either quantify the change in the expression of cell surface marker(s) associated with the process of activation of monocytes and DC following exposure to sensitisers (e.g. CD54, CD86) or the changes in IL-8 expression, a cytokine associated with the activation of DC. In the h-CLAT and U-SENS assays, the changes of surface marker expression are measured by flow cytometry following cell staining with fluorochrome-tagged antibodies. In the IL-8 Luc assay, the changes in IL-8 expression are measured indirectly via the activity of a luciferase gene under the control of the IL-8 promoter. The relative fluorescence or luminescence intensity of the treated cells compared to solvent/vehicle control are calculated and used in the prediction model, to support the discrimination between sensitisers and non-sensitisers.

This Test Guideline describes an in vitro procedure allowing the identification of chemicals (substances and mixtures) not requiring classification and labelling for eye irritation or serious eye damage in accordance with UN GHS. It makes use of reconstructed human cornea-like epithelium (RhCE) which closely mimics the histological, morphological, biochemical and physiological properties of the human corneal epithelium. The test evaluates the ability of a test chemical to induce cytotoxicity in a RhCE tissue construct, as measured by the MTT assay. Coloured chemicals can also be tested by used of an HPLC procedure. RhCE tissue viability following exposure to a test chemical is measured by enzymatic conversion of the vital dye MTT by the viable cells of the tissue into a blue MTT formazan salt that is quantitatively measured after extraction from tissues. The viability of the RhCE tissue is determined in comparison to tissues treated with the negative control substance (% viability), and is then used to predict the eye hazard potential of the test chemical. Chemicals not requiring classification and labelling according to UN GHS are identified as those that do not decrease tissue viability below a defined threshold (i.e., tissue viability > 60%, for UN GHS No Category).

This Test Guideline describes an in vitro assay that may be used for identifying water soluble ocular corrosives and severe irritants as defined by the UN Globally Harmonized System of Classification and Labelling, Category 1. The assay is performed in a well where a confluent monolayer of Madin-Darby Canine Kidney (MDCK) is used as a separation between two chambers. It uses a fluorescein dye as marqueur. The test substance has the potential to impair the junctions of the MDCK cells and thus to increase the monolayer¡¯s permeability. Consequently the fluorescein passes through the monolayer and the fluorescein leakage (FL) increases. The FL is calculated as a percentage of leakage relative to both a blank control and a maximum leakage control. The concentration of test substance that causes 20% FL (FL20, in mg/mL) is calculated and used in the prediction model for identification of ocular corrosive and severe irritants. The cut-off value of FL20 to identify water soluble chemicals as ocular corrosives/severe irritants is ¡Ü 100mg/mL. The FL test method should be part of a tiered testing strategy.

Skin phototoxicity (photoirritation) is defined as an acute toxic response elicited by topically or systemically administered photoreactive chemicals after the exposure of the skin to environmental light. The in vitro reconstructed human epidermis phototoxicity test (RhE PT) is used to identify the phototoxic potential of a test chemical after topical application in reconstructed human epidermis (RhE) tissues in the presence and absence of simulated sunlight. Phototoxicity potential is evaluated by the relative reduction in viability of cells exposed to the test chemical in the presence as compared to the absence of simulated sunlight. Chemicals identified as positive in this test may be phototoxic in vivo following topical application to the skin, eyes, and other external light-exposed epithelia.

This Test Guideline describes the Medaka Extended One Generation Test (MEOGRT), which exposes fish over multiple generations to give data relevant to ecological hazard and risk assessment of chemicals, including suspected endocrine disrupting chemicals (EDCs).  Exposure in the MEOGRT starts with spawning fish (P or F0 generation) and continues until hatching (until two weeks post fertilization, wpf) in the second (F2) generation. This Test Guideline measures several biological endpoints.  Primary emphasis is given to potential adverse effects on population relevant parameters including survival, gross development, growth and reproduction (fecundity).  Secondarily, in order to provide mechanistic information and provide linkage between results from other kinds of field and laboratory studies, where there is a posteriori evidence for a chemical having potential endocrine disrupter activity (e.g. androgenic or oestrogenic activity in other tests and assays) then other useful information is obtained by measuring vitellogenin (vtg) mRNA (or vitellogenin protein, VTG), phenotypic secondary sex characteristics (SSC) as related to genetic sex, and evaluating histopathology.

This Test Guideline (TG) describes a method to determine the hydrophobicity index (Hy) of nanomaterials (NMs), through an affinity measurement. Hydrophobicity is defined as "the association of non-polar groups or molecules in an aqueous environment which arises from the tendency of water to exclude non-polar molecules". By measuring their binding rate to different engineered surfaces (collectors), Hy expresses the tendency of the NMs to favour the binding to a non-polar (hydrophobic) surface because of its low affinity for water. The method applies to NMs dispersed in an aqueous solution or to NM powders after their dispersions in aqueous solutions, with or without a surfactant, using a recommended protocol.

This method provides information on health hazard likely to arise from exposure to test substance (liquids, solids and aerosols) by application on the eye. This Test Guideline is intended preferably for use with albino rabbit. The test substance is applied in a single dose in the conjunctival sac of one eye of each animal. The other eye, which remains untreated, serves as a control. The initial test uses an animal; the dose level depends on the test substance nature. A confirmatory test should be made if a corrosive effect is not observed in the initial test, the irritant or negative response should be confirmed using up to two additional animals. It is recommended that it be conducted in a sequential manner in one animal at a time, rather than exposing the two additional animals simultaneously. The duration of the observation period should be sufficient to evaluate fully the magnitude and reversibility of the effects observed. The eyes should be examined at 1, 24, 48, and 72 hours after test substance application. The ocular irritation scores should be evaluated in conjunction with the nature and severity of lesions, and their reversibility or lack of reversibility. Use of topical anesthetics and systemic analgesics to avoid or minimize pain and distress in ocular safety testing procedures is described.

This Test Guideline, covering nanomaterials spanning from 1 nm to 1000 nm, is intended for particle size and particle size distribution measurements of nanomaterials. The TG includes the following methods: Atomic Force Microscopy (AFM), Centrifugal Liquid Sedimentation (CLS)/Analytical Ultracentrifugation (AUC), Dynamic Light Scattering (DLS), Differential Mobility Analysis System (DMAS), (Nano)Particle Tracking Analysis (PTA/NTA), Small Angle X-Ray Scattering (SAXS), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). For measuring the diameter and length of fibres, analysing images captured with electron microscopy is currently the only method available.