Apesar de os defensivos agrícolas atualmente classificados como Poluentes Orgânicos Persistentes (POPs) terem sua produção e uso banidos na maior parte do mundo desde a década de 1980, o gerenciamento de estoques remanescentes permanece um desafio até a atualidade. Com estimativas que variam entre 500 mil (FAO, 2015) e 2 milhões de toneladas (VIJGEN et al., 2011), poucas informações sobre seu efetivo gerenciamento e destruição são encontradas nas principais bases de dados acadêmicas sobre o tema e nos documentos oficiais da Convenção de Estocolmo sobre Poluentes Orgânicos Persistentes. O Brasil integra a lista de signatários da Convenção, mas a fabricação, o armazenamento e o uso dos agrotóxicos POPs foram proibidos em 1985, por meio da Portaria do Ministério da Agricultura nº 329. Este abrupto banimento do armazenamento colocou o agricultor brasileiro imediatamente fora da lei, uma vez que não foram planejadas medidas e procedimentos legais para dar destino adequado aos produtos que ainda estivessem em estoque nas propriedades rurais. De forma independente da Convenção de Estocolmo e das ações nacionais relacionadas a este tratado, dois estados brasileiros elaboraram programas para o levantamento de estoque dos defensivos agrícolas banidos e planejamento de sua destinação. Finalizado em 2013, o Paraná incinerou cerca de 1.200 toneladas que estavam estocadas em mais de 2.000 propriedades rurais do estado. São Paulo finalizou o inventário em 2012, resultando em 420 toneladas estocadas em aproximadamente 330 propriedades rurais. O grupo de trabalho paulista planejou as etapas seguintes e em abril de 2016, o projeto se encontrava em fase de alocação de recursos para execução das fases finais de acondicionamento, transporte e destinação. A proposta deste projeto de pesquisa é apresentar como Paraná e São Paulo gerenciaram os estoques remanescentes de agrotóxicos banidos há décadas, avaliando como os grupos de trabalho foram formados, as normativas de apoio utilizadas, como foram realizadas as etapas de levantamento de inventário e de que forma foram planejadas, financiadas, comunicadas e executadas as etapas de coleta, acondicionamento, transporte e destinação. Dessa forma, busca-se contribuir para um aumento de conhecimento prático sobre o tema e para a construção de uma política pública para gerenciamento de agrotóxicos banidos em outros estados brasileiros. / Although the pesticides currently classified as Persistent Organic Pollutants (POPs) have had their production and use banned in most of the world since the 1980s, the management of remaining stocks remains a challenge to the present. With estimates ranging from 500,000 (FAO, 2015) and 2 million tons (Vijgen et al., 2011), little information about its effective management and destruction are found in major academic databases on the subject and official documents of the Stockholm Convention on Persistent Organic Pollutants. Brazil is one of the signatories but the manufacture, storage and use of pesticides POPs were banned in 1985 by the Ministry of Agriculture Decree No. 329. However, this abrupt ban put the Brazilian farmers immediately outside the law since the government did not plan measures and legal procedures to give proper destination to the products that were still in stock on farms. Independently of the Stockholm Convention and the National Plans related to this treaty, two Brazilian states have developed programs to inventory banned pesticides and plan their destination. Finished in 2013, Paraná State incinerated about 1,200 tons that had been stored in more than 2,000 rural properties. Sao Paulo finished its inventory in 2012 resulting in 420 tons stored in about 330 rural properties. The São Paulo working group has planned the next steps and, in April 2016, the project was waiting for resource in order to implement the final stages of packaging, transport and disposal. The purpose of this research is to present as Parana and Sao Paulo managed the remaining stocks of banned pesticides evaluating how the working groups were formed, the support normative used, how the inventory has been planned and carried out and how the projects have financed, communicated and executed the steps of collection, packaging, transportation and disposal. Thus, it is expected to contribute to increase the practical knowledge on the topic and to construct a public policy for pesticide management banned in other Brazilian states.

Novos poluentes orgânicos persistentes (POPs) têm sido adicionados à lista da Convenção de Estocolmo, exemplificado nesta pesquisa pelos éteres difenílicos polibromados (polybrominated diphenyl ethers-PBDEs) aplicados como retardantes de chama em diversos artigos de consumo (eletrônicos, têxteis, móveis, automóveis e na construção civil). São substâncias semi voláteis, persistentes no ambiente, bioacumulativos nos tecidos adiposos e podem interferir no sistema endócrino humano e dos animais. Os países signatários devem cumprir as medidas estabelecidas e enfrentam desafios para a sua implementação, a julgar pelos poucos países que atualizaram os Planos Nacionais de Implementação (National Implementation Plans-NIPs). Esta pesquisa teve por objetivo identificar os aspectos institucionais, legais, políticos e técnicos para a implementação das exigências oriundas da Convenção de Estocolmo, no que diz respeito aos PBDEs, realizar revisão sistematizada da literatura sobre os artigos colocados no mercado e em unidades de reciclagem de resíduos contendo PBDE e apresentar as experiências de dois países na implementação das medidas. O método de pesquisa de estudo de casos comparados, com o delineamento de casos mais diferentes com o mesmo resultado, foi empregado para a República Tcheca e a Suécia, apoiado por análise de congruência. Entrevistas foram realizadas com profissionais envolvidos com as atividades para a elaboração e a implementação da Convenção de Estocolmo. A revisão sistematizada para PBDEs indicou o aumento da quantidade de artigos científicos a partir de 2008 e os estudos revelaram a presença de PBDEs na poeira e no ar em ambientes internos, como residências e escritórios e nos ambientes internos e externos às instalações de reciclagem de resíduos com avaliação da exposição humana aos PBDEs, e novos estudos devem ser desenvolvidos. A revisão mostrou também que na América Latina e Caribe as publicações ainda são em pequeno número, mas o Brasil tem posição de destaque. O estudo dos dois países revelou que é requerida uma complexa abordagem para a transposição das medidas em âmbito nacional, incluindo legislação sobre gestão de produtos químicos, arranjos institucionais nacionais para a implementação do NIP apoiados por instituições de pesquisas científicas, existência de programas de monitoramento ambiental e de controle de POP-BDEs em artigos de consumo colocados no mercado. Os principais desafios técnicos são a segregação de plásticos, contendo PBDEs em parceria com o setor industrial para identificar o conteúdo PBDEs em artigos em uso que se tornarão resíduos e a viabilização do uso das alternativas tecnológicas. Os benefícios gerados pela implementação da Convenção são a proteção da saúde humana e do meio ambiente, a melhoria da governança, a promoção de assistência técnica, a maior visibilidade sobre riscos de uso de produtos tóxicos, em especial os POPs, a maior interação entre a ciência e as políticas públicas e o aumento das pesquisas cientificas. A Convenção de Estocolmo é um acordo complexo porém contribui com o entendimento mais amplo dos riscos químicos e sobre gestão coordenada das substâncias químicas. / Additional new Persistent Organic Pollutants (POPs) have been included to the list of Stockholm Convention, in the research exemplified by means of polybrominated diphenyl ethers (PBDEs) which resist degradation, are transported far from their place of release, where they accumulate in terrestrial and aquatic ecosystems and possess toxic properties, since they are classified as endocrine disruptive chemicals. They were used as brominated flame retardants and applied in many articles/consumer products such as electronics, textiles, vehicles, furniture and building materials. The signatories countries must comply with obligations and measures taken by Convention however they are facing many challenges in order to implement them, once few countries submitted the updated National Implementation Plans (NIPs) to the Convention. This research aims at identifying the institutional, legal, technical and politics aspects in order to transpose those measures to the national level, conducting a systematized research of literature on consumer products that may contain c-BDE put in the market besides recycling units of articles upon becoming wastes, consisting of, containing or contaminated with a chemical PBDEs and presenting the experience of two countries in implementing PBDEs actions plans of the NIPs. The comparative case studies was used as the research method, improved by the most different cases and most similar outcomes, designed for two countries as Czech Republic and Sweden, supported by the congruence analyses. Standardized interviews were applied to professionals involved in elaborating and implementing the Stockholm Convention in the countries. The systematized research indicated the increase from 2008 of the scientific number articles related to PBDEs which presented the occurrence of PBDEs in indoor house, office and recycling units dust and air internal and outdoor environments nearby waste electronic and electric equipment recycling units, with human exposure analyses related to and the researches must be continued, accordingly the conclusions. The comparative case studies of two countries revealed the requirement of a complex chemical substances management approach in order to transpose the PBDEs obligations to the national level, including the industrial chemical and environmental legislations, especially on POP-BDEs in products, a integrated institutional arrangement with the scientific institutional support, environmental monitoring programs and chemical control of the spread of POP-BDEs substances present in a number of consumer products put on the market; as the main challenges are the segregation of plastics containing PBDE in order to avoid recycled articles containing PBDEs and the importance of dialogue with the industrial sector in order to identify the PBDEs content in articles in use and to evaluate technology alternatives to PBDEs as well as promote technical capacities to raise awareness of chemicals to importers and private sector. The benefits generated by the Convention implementation are protection on healthy and environmental, the governance improvement, technical assistance promotion, POPs visibility, science and politics integration and the increase of scientific research.

Novos poluentes orgânicos persistentes (POPs) têm sido adicionados à lista da Convenção de Estocolmo, exemplificado nesta pesquisa pelos éteres difenílicos polibromados (polybrominated diphenyl ethers-PBDEs) aplicados como retardantes de chama em diversos artigos de consumo (eletrônicos, têxteis, móveis, automóveis e na construção civil). São substâncias semi voláteis, persistentes no ambiente, bioacumulativos nos tecidos adiposos e podem interferir no sistema endócrino humano e dos animais. Os países signatários devem cumprir as medidas estabelecidas e enfrentam desafios para a sua implementação, a julgar pelos poucos países que atualizaram os Planos Nacionais de Implementação (National Implementation Plans-NIPs). Esta pesquisa teve por objetivo identificar os aspectos institucionais, legais, políticos e técnicos para a implementação das exigências oriundas da Convenção de Estocolmo, no que diz respeito aos PBDEs, realizar revisão sistematizada da literatura sobre os artigos colocados no mercado e em unidades de reciclagem de resíduos contendo PBDE e apresentar as experiências de dois países na implementação das medidas. O método de pesquisa de estudo de casos comparados, com o delineamento de casos mais diferentes com o mesmo resultado, foi empregado para a República Tcheca e a Suécia, apoiado por análise de congruência. Entrevistas foram realizadas com profissionais envolvidos com as atividades para a elaboração e a implementação da Convenção de Estocolmo. A revisão sistematizada para PBDEs indicou o aumento da quantidade de artigos científicos a partir de 2008 e os estudos revelaram a presença de PBDEs na poeira e no ar em ambientes internos, como residências e escritórios e nos ambientes internos e externos às instalações de reciclagem de resíduos com avaliação da exposição humana aos PBDEs, e novos estudos devem ser desenvolvidos. A revisão mostrou também que na América Latina e Caribe as publicações ainda são em pequeno número, mas o Brasil tem posição de destaque. O estudo dos dois países revelou que é requerida uma complexa abordagem para a transposição das medidas em âmbito nacional, incluindo legislação sobre gestão de produtos químicos, arranjos institucionais nacionais para a implementação do NIP apoiados por instituições de pesquisas científicas, existência de programas de monitoramento ambiental e de controle de POP-BDEs em artigos de consumo colocados no mercado. Os principais desafios técnicos são a segregação de plásticos, contendo PBDEs em parceria com o setor industrial para identificar o conteúdo PBDEs em artigos em uso que se tornarão resíduos e a viabilização do uso das alternativas tecnológicas. Os benefícios gerados pela implementação da Convenção são a proteção da saúde humana e do meio ambiente, a melhoria da governança, a promoção de assistência técnica, a maior visibilidade sobre riscos de uso de produtos tóxicos, em especial os POPs, a maior interação entre a ciência e as políticas públicas e o aumento das pesquisas cientificas. A Convenção de Estocolmo é um acordo complexo porém contribui com o entendimento mais amplo dos riscos químicos e sobre gestão coordenada das substâncias químicas. / Additional new Persistent Organic Pollutants (POPs) have been included to the list of Stockholm Convention, in the research exemplified by means of polybrominated diphenyl ethers (PBDEs) which resist degradation, are transported far from their place of release, where they accumulate in terrestrial and aquatic ecosystems and possess toxic properties, since they are classified as endocrine disruptive chemicals. They were used as brominated flame retardants and applied in many articles/consumer products such as electronics, textiles, vehicles, furniture and building materials. The signatories countries must comply with obligations and measures taken by Convention however they are facing many challenges in order to implement them, once few countries submitted the updated National Implementation Plans (NIPs) to the Convention. This research aims at identifying the institutional, legal, technical and politics aspects in order to transpose those measures to the national level, conducting a systematized research of literature on consumer products that may contain c-BDE put in the market besides recycling units of articles upon becoming wastes, consisting of, containing or contaminated with a chemical PBDEs and presenting the experience of two countries in implementing PBDEs actions plans of the NIPs. The comparative case studies was used as the research method, improved by the most different cases and most similar outcomes, designed for two countries as Czech Republic and Sweden, supported by the congruence analyses. Standardized interviews were applied to professionals involved in elaborating and implementing the Stockholm Convention in the countries. The systematized research indicated the increase from 2008 of the scientific number articles related to PBDEs which presented the occurrence of PBDEs in indoor house, office and recycling units dust and air internal and outdoor environments nearby waste electronic and electric equipment recycling units, with human exposure analyses related to and the researches must be continued, accordingly the conclusions. The comparative case studies of two countries revealed the requirement of a complex chemical substances management approach in order to transpose the PBDEs obligations to the national level, including the industrial chemical and environmental legislations, especially on POP-BDEs in products, a integrated institutional arrangement with the scientific institutional support, environmental monitoring programs and chemical control of the spread of POP-BDEs substances present in a number of consumer products put on the market; as the main challenges are the segregation of plastics containing PBDE in order to avoid recycled articles containing PBDEs and the importance of dialogue with the industrial sector in order to identify the PBDEs content in articles in use and to evaluate technology alternatives to PBDEs as well as promote technical capacities to raise awareness of chemicals to importers and private sector. The benefits generated by the Convention implementation are protection on healthy and environmental, the governance improvement, technical assistance promotion, POPs visibility, science and politics integration and the increase of scientific research.

Apesar de os defensivos agrícolas atualmente classificados como Poluentes Orgânicos Persistentes (POPs) terem sua produção e uso banidos na maior parte do mundo desde a década de 1980, o gerenciamento de estoques remanescentes permanece um desafio até a atualidade. Com estimativas que variam entre 500 mil (FAO, 2015) e 2 milhões de toneladas (VIJGEN et al., 2011), poucas informações sobre seu efetivo gerenciamento e destruição são encontradas nas principais bases de dados acadêmicas sobre o tema e nos documentos oficiais da Convenção de Estocolmo sobre Poluentes Orgânicos Persistentes. O Brasil integra a lista de signatários da Convenção, mas a fabricação, o armazenamento e o uso dos agrotóxicos POPs foram proibidos em 1985, por meio da Portaria do Ministério da Agricultura nº 329. Este abrupto banimento do armazenamento colocou o agricultor brasileiro imediatamente fora da lei, uma vez que não foram planejadas medidas e procedimentos legais para dar destino adequado aos produtos que ainda estivessem em estoque nas propriedades rurais. De forma independente da Convenção de Estocolmo e das ações nacionais relacionadas a este tratado, dois estados brasileiros elaboraram programas para o levantamento de estoque dos defensivos agrícolas banidos e planejamento de sua destinação. Finalizado em 2013, o Paraná incinerou cerca de 1.200 toneladas que estavam estocadas em mais de 2.000 propriedades rurais do estado. São Paulo finalizou o inventário em 2012, resultando em 420 toneladas estocadas em aproximadamente 330 propriedades rurais. O grupo de trabalho paulista planejou as etapas seguintes e em abril de 2016, o projeto se encontrava em fase de alocação de recursos para execução das fases finais de acondicionamento, transporte e destinação. A proposta deste projeto de pesquisa é apresentar como Paraná e São Paulo gerenciaram os estoques remanescentes de agrotóxicos banidos há décadas, avaliando como os grupos de trabalho foram formados, as normativas de apoio utilizadas, como foram realizadas as etapas de levantamento de inventário e de que forma foram planejadas, financiadas, comunicadas e executadas as etapas de coleta, acondicionamento, transporte e destinação. Dessa forma, busca-se contribuir para um aumento de conhecimento prático sobre o tema e para a construção de uma política pública para gerenciamento de agrotóxicos banidos em outros estados brasileiros. / Although the pesticides currently classified as Persistent Organic Pollutants (POPs) have had their production and use banned in most of the world since the 1980s, the management of remaining stocks remains a challenge to the present. With estimates ranging from 500,000 (FAO, 2015) and 2 million tons (Vijgen et al., 2011), little information about its effective management and destruction are found in major academic databases on the subject and official documents of the Stockholm Convention on Persistent Organic Pollutants. Brazil is one of the signatories but the manufacture, storage and use of pesticides POPs were banned in 1985 by the Ministry of Agriculture Decree No. 329. However, this abrupt ban put the Brazilian farmers immediately outside the law since the government did not plan measures and legal procedures to give proper destination to the products that were still in stock on farms. Independently of the Stockholm Convention and the National Plans related to this treaty, two Brazilian states have developed programs to inventory banned pesticides and plan their destination. Finished in 2013, Paraná State incinerated about 1,200 tons that had been stored in more than 2,000 rural properties. Sao Paulo finished its inventory in 2012 resulting in 420 tons stored in about 330 rural properties. The São Paulo working group has planned the next steps and, in April 2016, the project was waiting for resource in order to implement the final stages of packaging, transport and disposal. The purpose of this research is to present as Parana and Sao Paulo managed the remaining stocks of banned pesticides evaluating how the working groups were formed, the support normative used, how the inventory has been planned and carried out and how the projects have financed, communicated and executed the steps of collection, packaging, transportation and disposal. Thus, it is expected to contribute to increase the practical knowledge on the topic and to construct a public policy for pesticide management banned in other Brazilian states.

South Africa ratified the Stockholm Convention (SC), which became legally binding on 17 May 2004. This Convention targets 12 particularly toxic persistent organic pollutants (POPs) for virtual elimination. The Convention also requires parties to reduce the release of organochlorine pesticides and the intentionally- and unintentionally-produced POPs such as dioxins, furans and polychlorinated biphenyls (PCBs) (referred to as dioxin-like chemicals). Dioxins are a heterogeneous mixture of chlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) congeners. These substances were never intentionally produced but are produced as by-products of industrial processes (such as metallurgical processes and bleaching of paper pulp). They can also be formed during natural processes such as volcanic eruptions and forest fires. The largest contributor to releases of PCDD/Fs in the environment is incomplete combustion from waste incinerators leading to the unintentional production of these compounds. Polychlorinated biphenyls (PCBs) are used in transformers and capacitors, but can also be formed unintentionally during industrial and thermal processes. Dioxin-like chemicals (PCDD/Fs and/or PCBs) are classified as persistent because of the following characteristics: lipophilicity and hydrophobicity; resistance to photolytic, chemical and biological degradation and they are able to travel long distances. As South Africa is a semiarid region, POPs will be less prone to travel here because these substances favour colder regions with high soil organic matter. Fish, predatory birds, mammals (including humans) absorb high concentrations of POPs through the process of bio-concentration, leading to bio-accumulation of these substances in the fatty tissue. PCDD/Fs occur as unwanted trace contaminants in air, water, land, in residues and products (such as consumer goods e.g. paper and textiles). The distribution of these chemicals into various matrices is problematic since they cause damage to the environment and human health. These chemicals pose a threat to human health when found in high concentrations that may lead to acute hepatoxicity and dermal toxicity (chloracne). Long-term exposure to low concentrations of these substances might lead to chronic effects such as reproductive problems and carcinogenicity. Since ferrous and non-ferrous metal production is a source of dioxin-like chemicals, a platinum mine in the Limpopo Province, South Africa, was selected for this investigation. The aim of the study was to determine if there are dioxin-like chemicals associated with platinum mining and processing, and if the H4IIE reporter gene bio-assay could be used to semi-quantify and assess the potencies of the complex environmental and process samples by determining their Toxic Equivalency Quotients (TEQ). The implications of the sources to the formation of dioxin-like chemicals regarding the SC were investigated and recommendations were made to improve this study. Samples were collected from tailings dams, woodchips, a dumpsite and slag from the smelter at Union Section. Samples were extracted with the Soxhlet apparatus using hexane as solvent. The percentage total organic carbon (%TOC) was determined for each sample to normalise the data. The method used was the Walkley-Black method. In determining the TEQ of each sample, the H4IIE luc cell line was used. The cells of the H4IIE luc line are genetically modified rat hepatoma cells stably transfected with a luciferase firefly gene. The luciferase gene is activated by the presence of dioxin-like compounds and the concentration of the enzyme is measured as relative light units (RLUs). The amount of RLUs is directly proportional to the dioxin load in the extract. This method is rapid, cost and time-effective in determining the TEQ when compared to chemical analysis. The TEQ2o-valuesin the various samples, as determined with the H4IIE luc cell line, ranged from 0.007 ngTEQ/kg to 54.06 ngTEQ/kg. Thermal processes at the smelter, sorption of hydrophobic organic compounds (HOCs) to soil and tailings, and external sources such as anthropogenic activities contributed to high TEQ2o-values. Climatic conditions, wind, precipitation, and solubility of HOCs into surfactants lead to low TEQ20. The smelter at Union Section had a very high TEQ20of 44.62 ngTEQ/kg compared to Impala Platinum mine (5.15 ngTEQ/kg). This implies that workers at Union Section are possibly exposed to low and high concentrations of dioxin-like chemicals. Long-term exposure to these compounds could lead to bio-accumulation in the fatty tissue of the mine workers, leading to chronic effects such as reproductive problems and cancer. The air emission of the furnace at the smelter was 0.03 gTEQ/annum and the release of the PCDD/Fs into the slag was 0.60 gTEQ/annum. By effectively managing the smelter it is possible to reduce the TEQ. The TEQ of each sample increased due to normalising the data. The normalised TEQ20 ranged from 0.94 ng TEQ/kg to 42497.48 ngTEQ/kg. Dioxin-like chemicals are present on a platinum mine, but at varying quantities and the effects of these compounds might be detrimental to the environment and the workers at the platinum mine. Further analyses of the health impacts associated with the platinum mine are needed. The H4IIE reporter gene bio-assay could be used to effectively determine the TEQ of each sample. Although this investigation has identified the formation and presence of dioxin-like chemicals at certain stages of mining and processing, not all of the processes were investigated. Some of these processes have the potential to add, and even destroy, these chemicals, affecting potential human exposure and amounts released to the environment. This, however, requires further investigation. The financial assistance of the National Research Foundation (NRF) towards this research is hereby acknowledged. Opinions expressed and conclusions arrived at, are those of the author and are not necessarily to be attributed to the NRF. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2006.

South Africa ratified the Stockholm Convention (SC), which became legally binding on 17 May 2004. This Convention targets 12 particularly toxic persistent organic pollutants (POPs) for virtual elimination. The Convention also requires parties to reduce the release of organochlorine pesticides and the intentionally- and unintentionally-produced POPs such as dioxins, furans and polychlorinated biphenyls (PCBs) (referred to as dioxin-like chemicals). Dioxins are a heterogeneous mixture of chlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) congeners. These substances were never intentionally produced but are produced as by-products of industrial processes (such as metallurgical processes and bleaching of paper pulp). They can also be formed during natural processes such as volcanic eruptions and forest fires. The largest contributor to releases of PCDD/Fs in the environment is incomplete combustion from waste incinerators leading to the unintentional production of these compounds. Polychlorinated biphenyls (PCBs) are used in transformers and capacitors, but can also be formed unintentionally during industrial and thermal processes. Dioxin-like chemicals (PCDD/Fs and/or PCBs) are classified as persistent because of the following characteristics: lipophilicity and hydrophobicity; resistance to photolytic, chemical and biological degradation and they are able to travel long distances. As South Africa is a semiarid region, POPs will be less prone to travel here because these substances favour colder regions with high soil organic matter. Fish, predatory birds, mammals (including humans) absorb high concentrations of POPs through the process of bio-concentration, leading to bio-accumulation of these substances in the fatty tissue. PCDD/Fs occur as unwanted trace contaminants in air, water, land, in residues and products (such as consumer goods e.g. paper and textiles). The distribution of these chemicals into various matrices is problematic since they cause damage to the environment and human health. These chemicals pose a threat to human health when found in high concentrations that may lead to acute hepatoxicity and dermal toxicity (chloracne). Long-term exposure to low concentrations of these substances might lead to chronic effects such as reproductive problems and carcinogenicity. Since ferrous and non-ferrous metal production is a source of dioxin-like chemicals, a platinum mine in the Limpopo Province, South Africa, was selected for this investigation. The aim of the study was to determine if there are dioxin-like chemicals associated with platinum mining and processing, and if the H4IIE reporter gene bio-assay could be used to semi-quantify and assess the potencies of the complex environmental and process samples by determining their Toxic Equivalency Quotients (TEQ). The implications of the sources to the formation of dioxin-like chemicals regarding the SC were investigated and recommendations were made to improve this study. Samples were collected from tailings dams, woodchips, a dumpsite and slag from the smelter at Union Section. Samples were extracted with the Soxhlet apparatus using hexane as solvent. The percentage total organic carbon (%TOC) was determined for each sample to normalise the data. The method used was the Walkley-Black method. In determining the TEQ of each sample, the H4IIE luc cell line was used. The cells of the H4IIE luc line are genetically modified rat hepatoma cells stably transfected with a luciferase firefly gene. The luciferase gene is activated by the presence of dioxin-like compounds and the concentration of the enzyme is measured as relative light units (RLUs). The amount of RLUs is directly proportional to the dioxin load in the extract. This method is rapid, cost and time-effective in determining the TEQ when compared to chemical analysis. The TEQ2o-valuesin the various samples, as determined with the H4IIE luc cell line, ranged from 0.007 ngTEQ/kg to 54.06 ngTEQ/kg. Thermal processes at the smelter, sorption of hydrophobic organic compounds (HOCs) to soil and tailings, and external sources such as anthropogenic activities contributed to high TEQ2o-values. Climatic conditions, wind, precipitation, and solubility of HOCs into surfactants lead to low TEQ20. The smelter at Union Section had a very high TEQ20of 44.62 ngTEQ/kg compared to Impala Platinum mine (5.15 ngTEQ/kg). This implies that workers at Union Section are possibly exposed to low and high concentrations of dioxin-like chemicals. Long-term exposure to these compounds could lead to bio-accumulation in the fatty tissue of the mine workers, leading to chronic effects such as reproductive problems and cancer. The air emission of the furnace at the smelter was 0.03 gTEQ/annum and the release of the PCDD/Fs into the slag was 0.60 gTEQ/annum. By effectively managing the smelter it is possible to reduce the TEQ. The TEQ of each sample increased due to normalising the data. The normalised TEQ20 ranged from 0.94 ng TEQ/kg to 42497.48 ngTEQ/kg. Dioxin-like chemicals are present on a platinum mine, but at varying quantities and the effects of these compounds might be detrimental to the environment and the workers at the platinum mine. Further analyses of the health impacts associated with the platinum mine are needed. The H4IIE reporter gene bio-assay could be used to effectively determine the TEQ of each sample. Although this investigation has identified the formation and presence of dioxin-like chemicals at certain stages of mining and processing, not all of the processes were investigated. Some of these processes have the potential to add, and even destroy, these chemicals, affecting potential human exposure and amounts released to the environment. This, however, requires further investigation. The financial assistance of the National Research Foundation (NRF) towards this research is hereby acknowledged. Opinions expressed and conclusions arrived at, are those of the author and are not necessarily to be attributed to the NRF. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2006.

Chemicals offer a wide range of desired functions and are used in a variety of consumer goods and industrial sectors. The number of individual synthetic organic chemicals produced and the total global chemical production volume are increasing. The majority of these anthropogenic chemicals are not monitored in environmental matrices nor in the indoor environment even though some are associated with undesirable consequences and the range of possible chemical impacts is still far from being fully understood. Chemicals that remain in the environment for a long time and/or distribute over a large area have high exposure potential, and will present particularly acute challenges if a currently unknown undesirable effect is discovered.  This thesis describes the development of a set of in silico methods to identify and prioritize chemicals with high exposure potential that are currently not subject to national or international restrictions. In brief, we i) compiled databases of contaminants of potential concern, ii) established models to predict key properties to fill data gaps in the absence of experimental data, and iii) developed and applied methods to screen chemicals to identify those that should be assigned high priority for future study.  Paper I delivers screening-level models to predict partition ratios of organic chemicals between polymeric materials commonly found indoors, and both air and water. These models can be used in high-throughput exposure assessment studies, passive sampling experiments, and models of emissions, fate and transport of chemicals.  Paper II presents a scoring method to prioritize 464 organic chemicals of emerging Arctic concern for their potential to fit a set of four exposure-based hazard profiles. These four profiles represent persistent organic pollutants (POPs) regulated under the Stockholm Convention, very persistent and very bioaccumulative substances (vPvBs) regulated under REACH and for two novel and unregulated profiles derived from the planetary boundary threats framework; airborne persistent contaminants (APCs) and waterborne persistent contaminants (WPCs). APCs and WPCs are chemicals that are mobile in air and water, respectively, and that contaminate the environment in a poorly reversible manner due to their persistence. The prioritization method is based on a reference set of 148 chemicals that is used to contextualize the scoring results.  Paper III describes the prioritization of 8,648 chemicals that were reportedly produced in five OECD countries. Paper III elucidates the relationship between the elemental composition of these chemicals and the exposure-based hazard scores, and presents a strategy to disentangle overlaps among the four exposure hazard profiles by categorizing chemicals according to the spatial coverage of profiles they best fit.  Paper IV focuses on refining the prioritization method described in Papers II and III using a set of 5,600 hypothetical chemicals. The refined method is used to prioritize the chemicals from Papers II and III, and an additional 4,567 chemicals from the REACH database.  The in silico methods developed in this thesis can be applied to conduct screening-level exposure assessments using only chemical structures as a starting point. Substances prioritized as having high potential to be POPs, vPvB, APC, or WPC should be considered for more detailed study to unequivocally determine their identity and physicochemical properties. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>

La scène internationale se caractérise par des relations de diverses natures entre les États. Pourtant, en observant plus attentivement, on se rend compte que cette coopération prend des tournures non linéaires sous le prisme des considérations financières. En effet, le financement est devenu le dénominateur qui façonne les relations interétatiques. Le droit international de l’environnement en général, et le secteur des produits chimiques et des déchets dangereux en particulier, n’échappe pas à ce paradigme. L’essentiel des échanges internationaux a pour trame de fond, l’exploitation des ressources naturelles et le commerce. Or depuis la deuxième et la troisième révolution industrielle, l’homme a appris à extraire et transformer les minerais et à synthétiser de nouvelles molécules pour la fabrication de produits de toute sorte. La surexploitation des ressources naturelles a parallèlement généré des retombées environnementales indésirables en termes de pollution transfrontière et d’atteintes graves sur la santé humaine. Cet état de choses a progressivement conduit à l’adoption d’instruments juridiques internationaux pour en limiter ou éradiquer les effets. C’est dans ce contexte que sont nées les Conventions de Bâle, de Rotterdam, de Stockholm, et récemment, la Convention de Minamata sur le mercure. Ces quatre instruments juridiques forment le système légal dans le secteur des produits chimiques et déchets dangereux. Toutefois, l’efficacité de cet arsenal passe inévitablement par la mise en œuvre de ces conventions. Or force est de constater que les choses ne sont pas aussi faciles dans la pratique. Le principal point d’achoppement réside très souvent dans les questions de financement des surcoûts que leur application entraîne dans les pays en voie de développement. Qui doit payer? La réponse à cette question passe par l’explication et l’interprétation du Principe des responsabilités communes mais différenciées et l’analyse de l’efficacité des mécanismes de financement mis en place dans le cadre de chaque convention. Face à ces préoccupations liées au financement, la question qu’on peut se poser est celle de savoir si le régime juridique n’est pas la source du problème. De plus, quel est l'impact des tentatives de restructuration entamées depuis quelques années? Quelles améliorations peuvent être proposées? C’est à cet ensemble de préoccupations que cette thèse apporte des réponses. / The international scene is marked by different types of interstate relationships. However, upon close consideration, this collaboration takes on a non-linear appearance from a financial point of view. In fact, funding has become the common denominator that shapes interstate relationships. International environmental law, as well as the chemical industry - particularly the hazardous waste sector - do not escape this paradigm. The exploitation of natural resources and trade constitute the foundation of this vital area of international exchanges. Since the second and third industrial revolutions, man has learned to extract and transform minerals and synthesize new molecules in order to manufacture of all sorts of products. The overexploitation of natural resources has by the same token led to undesirable environmental impacts in the form of transboundary contamination and severe damage to human health. This state of affairs has gradually led to the adoption of international legal instruments with a view to limiting or eradicating the aforementioned effects. It was within this context that the Basel, Rotterdam, Stockholm and, most recently, the Minamata Convention on Mercury were adopted. These four legal instruments form the legal structure in the chemicals and hazardous waste sector. However, the effectiveness of this arsenal involves the implementation of these conventions. But this is not as easy in practice. The main stumbling block is often the question of financing the additional costs that their implementation entails in developing countries. Who should pay? The answer to this question lies in the explanation and interpretation of the principle of common but differentiated responsibilities and the analysis of the effectiveness of the financing mechanisms set up under each convention. In the face of these funding concerns, the question that can be asked is whether the legal regime is not the source of the problem. Moreover, what is the impact of the restructuring attempts initiated in recent years? What improvements can be proposed? It is to this set of concerns that this thesis provides answers.

In the United Nations Convention on the Law of the Sea, the environmental protection of the marine environment was first addressed in a comprehensive manner on an international level. However, the Convention distinguishes between four different sorts of pollution depending on which source the pollution originates from. Still, one of these sources play a more crucial role in the protection of the marine environment than the other since that source is estimated to stand for 80 percent of all the marine pollution; namely marine pollution from land-based sources. As the throw-away culture has led to products being disposed of at a faster rate than ever before, in particular plastic products, the amount of land-based debris has also substantially increased over the last decades. This increased disposal rate of products in combination with poor waste treatment has consequently led to many kinds of wastes ending up in the ocean and causing severe harm, not only to the marine environment and its living species, but also to humans that eat the fish and use the many other ecosystem services of the Sea. In this thesis, some prominent international conventions on marine pollution from land-based sources are examined; namely the United Nations Convention on the Law of the Sea, the Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal, as well as the Stockholm Convention on Persistent Organic Pollutants. To achieve United Nations Sustainable Development Goal number 14.1 to significantly reduce marine pollution from land-based sources by 2025, this thesis claims that international laws addressing this sort of pollution need to be implemented. Moreover, this thesis rests on the belief that regional implementation is a crucial component in making states align with international law. However, while regional implementation has been ambitious in the European Union Law, many regions still lack enforceable frameworks that aim to reduce and prevent marine pollution from land-based sources.