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Industrial chemicals have become an integral part of modern life, and they infiltrate into a lot of activities of human beings, such as industrial manufacturing, agriculture, pharmaceutics, etc. Globalization brings opportunity and challenge to developing countries on the sound management of industrial chemicals (SMC). The issue is the contradiction between unmatched increasing import and consumption and weak legislation on SMC in developing countries. Consequently, more health and environmental impacts have been reported in developing countries because they lack capacities to generate sufficient information on chemical risks as well as appropriate methods for assessment and monitoring. Developed countries and IGOs (Intergovernmental Organizations) have made a lot of efforts on sound management of chemicals since 1960s. However, these efforts remain highly fragmented at international and national levels. As a result, a clear and well articulated strategy and concerted efforts from the international community to help developing countries is required. The aim of this thesis is, based on the studies of existing guidelines made by different IGOs on SMC, to suggest an integrated framework which can be used to collaborate with these scattered efforts together, to create synergies and avoid overlaps. This suggested framework consists of an executive mechanism which includes a panel of international organizations and general guidelines on SMC. Such a framework, looking like a voluntary intentional framework, provides possibilities to improve the capacity of developing countries’ management on industrial chemicals. To effective the framework, it needs shared responsibility of many actors to work together with same objectives to reduce adverse effects on human health and the environment. So this thesis just make a hypothesis based on the study of existing status on SMC, do the feasibility discussion and collect some feedbacks from IGOs as well.

This thesis deals with diffusion and flow of sub-critical hydrocarbons in activated carbon by using a differential permeation method. The hydrocarbons are selected according to the effect on environmental concerns and their unique characteristics such as polarity and affinity towards activated carbon. Although it has been known that transport processes in activated carbon consist of Knudsen diffusion, gaseous viscous flow, adsorbed phase diffusion (so called, surface diffusion) and condensate flow, there have been no rigorous models to describe the transport processes in activated carbon with a full range of pressures. In particular among the four processes, the mechanism of adsorbed phase diffusion in activated carbon is still far from complete understanding. Also due to the dispersion interactions between adsorbing molecules and the solid surface, one would expect that Knudsen diffusion is influenced by the dispersive forces. From intensive experimental observations with a great care over a full range of pressures, conventional methods (for example, direct estimation from inert gas experiments) to determine adsorbed phase diffusion are found to be inadequate for strongly adsorbing vapors in activated carbon. By incorporating the effect of adsorbate-adsorbent interactions into Knudsen diffusivity, the general behavior of adsorbed phase diffusion in terms of pressure (or surface loading) can be obtained, showing a significant role in transport at low pressures. For non-polar hydrocarbons such as benzene, carbon tetrachloride and n-hexane, a mathematical model, which accounts for the effects of adsorbate-adsorbent interactions and pore size distribution, is formulated and validated, resulting in a good agreement with experimental data. Moreover, the adsorption and dynamic behaviors of alcohol molecules (which are polar compounds) are investigated with an aim to compare their behaviors against those of non-polar compounds.

<p>For the majority of the estimated 70,000 industrial chemical substances available on the European market today there is not enough information to enable a reasonably complete assessment of the risks that they might pose to man and the environment. Any strategy for the generation of additional data for these substances should aim at making testing as efficient as possible taking into account environmental and health protection, time, monetary cost and animal welfare. To achieve this, appropriate priority setting rules are needed.</p><p>The main criterion currently used for regulatory priority setting for testing of industrial chemicals is production volume; the higher the production volume, the more information is required. This was also the main criterion in the former legislation, preceding REACH (Registration, Evaluation and Authorisation of Chemicals). The aim of this thesis is to evaluate other priority setting criteria and their implications for risk management, in particular classification and labelling.</p><p>The first paper in this thesis includes a study of the<i> efficiency ratio</i> for some of the tests required for the notification of new substances, i.e. the ratio between the likelihood that the test will lead to a classification, and the monetary cost of performing the test. The efficiency ratio was determined for the standard tests for acute oral toxicity, irritation, sensitisation and subacute toxicity using data from 1409 new chemicals notified in Europe between 1994 and 2004. The results of this investigation suggest that, given limited resources for testing, it is more efficient to perform acute toxicity tests on a larger number of substances rather than to perform additional subacute toxicity studies on the substances already tested for acute toxicity.</p><p>The second paper included in this thesis, reports the results from a comparative study of the bioaccumulating properties of substances being (a) classified as carcinogenic, mutagenic and/or toxic to reproduction (CMR-substances), or (b) classified as acutely toxic or (c) unclassified. The purpose of this investigation was to evaluate potential consequences of prioritising bioaccumulating chemicals for evaluation and testing, as this is one of the strategies prescribed in REACH. The results of this study suggest that bioaccumulating substances are neither over- nor underrepresented among the CMR-substances. This result lends support to the use of the bioconcentration factor for priority setting.</p><p>The studies reported in this thesis utilize existing data on classification of substances as an indicator of the outcome of the risk assessment process, relating priority setting methods to the risk management measures that they give rise to. To the best of my knowledge there are still only very few studies published that address the issue of priority setting in chemicals control using this approach, and in my view there is need for more studies of priority setting methods and a further development of priority setting strategies that are science-based.</p>

This thesis deals with diffusion and flow of sub-critical hydrocarbons in activated carbon by using a differential permeation method. The hydrocarbons are selected according to the effect on environmental concerns and their unique characteristics such as polarity and affinity towards activated carbon. Although it has been known that transport processes in activated carbon consist of Knudsen diffusion, gaseous viscous flow, adsorbed phase diffusion (so called, surface diffusion) and condensate flow, there have been no rigorous models to describe the transport processes in activated carbon with a full range of pressures. In particular among the four processes, the mechanism of adsorbed phase diffusion in activated carbon is still far from complete understanding. Also due to the dispersion interactions between adsorbing molecules and the solid surface, one would expect that Knudsen diffusion is influenced by the dispersive forces. From intensive experimental observations with a great care over a full range of pressures, conventional methods (for example, direct estimation from inert gas experiments) to determine adsorbed phase diffusion are found to be inadequate for strongly adsorbing vapors in activated carbon. By incorporating the effect of adsorbate-adsorbent interactions into Knudsen diffusivity, the general behavior of adsorbed phase diffusion in terms of pressure (or surface loading) can be obtained, showing a significant role in transport at low pressures. For non-polar hydrocarbons such as benzene, carbon tetrachloride and n-hexane, a mathematical model, which accounts for the effects of adsorbate-adsorbent interactions and pore size distribution, is formulated and validated, resulting in a good agreement with experimental data. Moreover, the adsorption and dynamic behaviors of alcohol molecules (which are polar compounds) are investigated with an aim to compare their behaviors against those of non-polar compounds.

This thesis deals with diffusion and flow of sub-critical hydrocarbons in activated carbon by using a differential permeation method. The hydrocarbons are selected according to the effect on environmental concerns and their unique characteristics such as polarity and affinity towards activated carbon. Although it has been known that transport processes in activated carbon consist of Knudsen diffusion, gaseous viscous flow, adsorbed phase diffusion (so called, surface diffusion) and condensate flow, there have been no rigorous models to describe the transport processes in activated carbon with a full range of pressures. In particular among the four processes, the mechanism of adsorbed phase diffusion in activated carbon is still far from complete understanding. Also due to the dispersion interactions between adsorbing molecules and the solid surface, one would expect that Knudsen diffusion is influenced by the dispersive forces. From intensive experimental observations with a great care over a full range of pressures, conventional methods (for example, direct estimation from inert gas experiments) to determine adsorbed phase diffusion are found to be inadequate for strongly adsorbing vapors in activated carbon. By incorporating the effect of adsorbate-adsorbent interactions into Knudsen diffusivity, the general behavior of adsorbed phase diffusion in terms of pressure (or surface loading) can be obtained, showing a significant role in transport at low pressures. For non-polar hydrocarbons such as benzene, carbon tetrachloride and n-hexane, a mathematical model, which accounts for the effects of adsorbate-adsorbent interactions and pore size distribution, is formulated and validated, resulting in a good agreement with experimental data. Moreover, the adsorption and dynamic behaviors of alcohol molecules (which are polar compounds) are investigated with an aim to compare their behaviors against those of non-polar compounds.

This thesis deals with diffusion and flow of sub-critical hydrocarbons in activated carbon by using a differential permeation method. The hydrocarbons are selected according to the effect on environmental concerns and their unique characteristics such as polarity and affinity towards activated carbon. Although it has been known that transport processes in activated carbon consist of Knudsen diffusion, gaseous viscous flow, adsorbed phase diffusion (so called, surface diffusion) and condensate flow, there have been no rigorous models to describe the transport processes in activated carbon with a full range of pressures. In particular among the four processes, the mechanism of adsorbed phase diffusion in activated carbon is still far from complete understanding. Also due to the dispersion interactions between adsorbing molecules and the solid surface, one would expect that Knudsen diffusion is influenced by the dispersive forces. From intensive experimental observations with a great care over a full range of pressures, conventional methods (for example, direct estimation from inert gas experiments) to determine adsorbed phase diffusion are found to be inadequate for strongly adsorbing vapors in activated carbon. By incorporating the effect of adsorbate-adsorbent interactions into Knudsen diffusivity, the general behavior of adsorbed phase diffusion in terms of pressure (or surface loading) can be obtained, showing a significant role in transport at low pressures. For non-polar hydrocarbons such as benzene, carbon tetrachloride and n-hexane, a mathematical model, which accounts for the effects of adsorbate-adsorbent interactions and pore size distribution, is formulated and validated, resulting in a good agreement with experimental data. Moreover, the adsorption and dynamic behaviors of alcohol molecules (which are polar compounds) are investigated with an aim to compare their behaviors against those of non-polar compounds.

This thesis deals with diffusion and flow of sub-critical hydrocarbons in activated carbon by using a differential permeation method. The hydrocarbons are selected according to the effect on environmental concerns and their unique characteristics such as polarity and affinity towards activated carbon. Although it has been known that transport processes in activated carbon consist of Knudsen diffusion, gaseous viscous flow, adsorbed phase diffusion (so called, surface diffusion) and condensate flow, there have been no rigorous models to describe the transport processes in activated carbon with a full range of pressures. In particular among the four processes, the mechanism of adsorbed phase diffusion in activated carbon is still far from complete understanding. Also due to the dispersion interactions between adsorbing molecules and the solid surface, one would expect that Knudsen diffusion is influenced by the dispersive forces. From intensive experimental observations with a great care over a full range of pressures, conventional methods (for example, direct estimation from inert gas experiments) to determine adsorbed phase diffusion are found to be inadequate for strongly adsorbing vapors in activated carbon. By incorporating the effect of adsorbate-adsorbent interactions into Knudsen diffusivity, the general behavior of adsorbed phase diffusion in terms of pressure (or surface loading) can be obtained, showing a significant role in transport at low pressures. For non-polar hydrocarbons such as benzene, carbon tetrachloride and n-hexane, a mathematical model, which accounts for the effects of adsorbate-adsorbent interactions and pore size distribution, is formulated and validated, resulting in a good agreement with experimental data. Moreover, the adsorption and dynamic behaviors of alcohol molecules (which are polar compounds) are investigated with an aim to compare their behaviors against those of non-polar compounds.