Recent environmental problems, such as air pollution caused by SO₂, NO_x, and volatile organic compounds and green house effect by CO₂, water pollution caused by low molecular weight organics like trichloroethane, agricultural chemicals and nitrates, and contamination of drinking water supplies by harmful compounds, were surveyed.
Membrane technology has high potential for solving the problems, and the current performance of gas and vapor separation membranes, reverse osmosis and nanofiltration membranes and pervaporation membranes was reviewed.

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Aplications of membrane processes to SO₂ and CO₂ removal from flue gas are roughly evaluated based on a boiler of 1, 000 MW power plant.
We can find out high-selective membrane mateials for SO₂/N₂ (more than α=20, 000) in the literature. Assuming the possibility of manufacturing of membranes with 0.1μm thickness, we can expect that the membrane process has a great advantage comparing to the conventional SO₂ removal process.
Membrane processes have also a great possibility for the CO₂ removal from the flue gas if the CO₂ permeation rate increases up to 5 times and the membrane cost decreases to 25% compared with curently available membranes. These assumptions seems to be realistic in the near future considering recent improvements of membrane materials and developments of commercial markets. Further improvement of the membrane selectivity for CO₂/N₂ could offer a more economical separation process for CO₂ removal.
In the future inorganic membranes are required for the high temperature application of the separation of pollutants from a synthesis gas of coal gasification.

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The vapors which are generated during storage, transportation and handling of volatile organic compounds (VOC) such as organic solvents and gasoline are contributing factors to the development of photochemical smog (oxidants) when released to the atmosphere. A number of other environmental problems are also attributed to VOC emissions, and the adoption of membrane processes has been finding increasing public acceptance as the best available emission control technology.
In this article, the legislation trends which are affected by the growing public awareness of environmental issues caused by VOC emissions will be surveyed. The characteristics of the composite membranes and membrane modules for VOC emission control, which have been developed by Nitto Denko (Japan), MTR (USA) and GKSS (Germany), will be reported. Various membrane processes for VOC removal and recovery will be summarized, and the processes applied to the following commercialized plants will be described : 1) gasoline vapor recovery system by membrane-absorption, 2) gasoline vapor recovery system by absorption-membrane combined with activated carbon PSA, 3) condensation-membrane system to recover HCFC-123 or CFC-12 etc., and other examples.

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Contamination of drinking water supplies by the harmful chemicals increases sharply, and it is important to remove harmful chemicals in drinking water supplies for keeping our health. The purpose of this study was to review the reverse osmosis membrane proesses available for removing harmful chemicals, such as agricultural chemicals, nitrates and trihalomethanes in ground water and river water, to acceptable limits for consumers.
Reverse osmosis membrane processes are used practically in the U.S.A. for the removal of nitrates and the prevent of trihalomethane formation by the chlorine applied for disinfection of drinking water. Reverse osmosis membrane process is one of the useful methods for making the safe drinking water.

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A three-years' comprehensive research project on application of micro-and ultrafiltration technology to public water supply was conducted with an initiative of the Ministry of Health and Welfare (MHW), Japanese Government. One of the main components of the project was a demonstration experiment by eighteen water treatment plant manufacturers. The experiment with totally thirty-five different microand ultrafiltration systems proved their practical applicability to water purification for public water supply in respect to water production capability, contaminant rejection, energy consumption and reliability. Based on the result of the project, a draft of the guidelines on introduction of a membrane filtration facility in small-scale water supplies was prepared. The MHW is going to give an approval to small-scale water supplies for their application of micro-and ultrafiltration facility according to the guidelines. The MHW is also going to launch a new three-years' comprehensive reseach project focusing mainly on micro-and ultrafiltration, in combination with other unit processes such as activated carbon adsorption, and nanofiltration for the removal of THM precursors and other microorganic pollutants in water.

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History reveals that cosmetics have been used since ancient days. Todays, cosmetics are used for differnt purpose with different meanings.
With the progress of science, a varieties of cosmetics having unique properties have appear on the market. Cosmetics are influenced by governments regulation, scientific technology, economical conditions and environmental problems including biological safety to human. The skin consists of epidermis layer and dermal layer which are important to cosmetics development. The thickness of the skin, excluding subcutaneous tissue, varies from 1.5 mm to 4.0 mm, It is very thin but has many protective effects.
The roles of cosmetics are to aid the functional of the skin, hair and nail as well as to make them beautify. From the considerations of the membranes, it is possible to divide the roles into treatment membrane, functinal membrane, efficacy membrane and beautifying membrane.
Treatment membrane is a cosmetics membrane that is formed by washing, cleansing and moisturizing. Functional membrane protects the skin from UV-lights. Efficacy membrane is formed by cosmetics having physiological effects. Finally, beautifying membrane is provided by cosmetics that alter appearance of the human body.

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Drug delivery system is simply defined as a technology to precisely control in vivo fate of drugs for achieving optimal therapeutic efficacy. In order to realize this goal, we should elucidate the molecular mechanism of each transport process and understand characteristics of the total body system. Based on these considerations, we have systematically investigated the mechanism of percutaneous drug absorption and in vivo disposition of macromolecules. In the former research, we have succeeded to elucidate action mechanism of absorption enhancers from a physicochemical viewpoint based on a skin diffusion model and demonstrated efficacy of an approach combining prodrug modification and the enhancer. In the latter study, systemic disposition features of macromolecules were explored in relation to their physicochemical and biological properties, and a strategy for designing targeting system was constructed. Novel delivery systems for cell-specific targeting utilizing receptormediated endocytosis are also developed.

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The concept of DDS (Drug Delivery System), involving the concept of TTS (Transdermal Therapeutic System), was created in recent years in an attempt to obtain maximal therapeutic effects of drugs whose clinical usefulness was established. Recent progress in DDS and TTS technologies depends in large part on the development and advance of polymer science, especially the improvement of techinologies utilizing polymer membranes. Two classes of membranes play a major role in transdermal absorbability of drugs in TTS, i.e., systhetic polymer membranes containes in the TTS preparations and the human skin acting as a defensive barrier. To reduce the barrier property of the horny layer of the human skin the developmement of efficient absorption enhancers constitutes a crucial point for the development of useful TTS preparations.
The determination of diffusion coefficients is essential to predict drug adsorbability in TTS, and several theoretical formulae (e.g., Fick's laws for solute permeation, absolute reaction theory for drug permeation analysis, and permeation theory of electrically charged solute) have been applied for such purpose. The development of TTS chiefly consists in the development of the system (i.c., reservoir type or matrix type) and the development of methods of enhancing drug transdermal adsorbability (i.e., transdermal absorption enhancers, transdermal absorption enhancing compositions, iontophoresis, and prodrugs).
The development of TTS preparations is intimately associated with the research and development of polymer membranes. Namely, it is true that not only the TTS preparations make use of polymer membranes, but also most of reserch approaches and procedures in TTS depend on polymer (membrane) science.

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In order to develop the magnetic thin film, we studied the structure and magnetic properties in the Langmuir-Blodgett (LB) multilayers of transition metal ion-fatty acid salt, using X-ray diffraction and electron paramagnetic resonance (EPR) methods. We found the various orientation as a function of multiplicity of layers in the LB films. In the film having more than four layers, the long molecular axis of fatty acid exhibits an apparent tilt structure; but in the film less than three layers, the molecular axis holds the perpendicular position against the substrate plane. Using the vector EPR measurements, we found the anomalous broadening of line shape due to the exchange interaction between successive layers. We concluded that the LB films of the transition metal ion-fatty acid salts may allow the highly ordered and the low-dimensional magnetic system.

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The hydraulic conductivity and water driving forces of a rat submandibular gland were measured by the pressure-metric method. A polyethylene tube was inserted into a main duct of a rat submandibular gland and connected to a narrow vertical tube. The level of fluid was monitored by a pressure transducer. Differentiation of the pressure curve with respect to time gave the volume flow curve. A part of relationship between flow and pressure was linear, and its slope gave the hydraulic conductivity of a gland. We compared the values of hydraulic conductivity under three conditions : 1) secretion of the perfused gland evoked by acetylcholine, 2) secretion evoked by Phenylephrine, 3) passive absorption of fluid performed with 0.15 MNaCl+Amiloride 10^-5 M. The values of hydraulic conductivity were very high with little difference between the stimulating and resting phases, and their values were about 2.4-2.6 × 10^-10 1 sec^-1 Pa^-1 kg^-1.

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Recently, Micro filtration (MF) or Ultra filtration (UF) are being developed as a filter for high concentrated solution of suspended solids. Sterapore L is an ultramicro filter of unique screen-like structure made of micro porous hallow fiber membrane and is superior for this purpose.

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