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This volume reviews in detail the structure and activities of the European Conference of Ministers of Transport during 1979. The work of the Conference and its subsidiary bodies is described in sectoral chapters. The report reviews co-operation with OECD Committees concerned with transport issues and with international organisations such as Council of Europe, the Economic Commission for Europe, European Economic Community. The report also contains a chapter on transport policy in member countries with particular reference to points of comparison between those policies and the Conference’s own action.
This Test Guideline describes methods to measure the viscosity of liquids.
The methods listed are appropriate in principle for the investigation of Newtonian liquids. The measurement of non-Newtonian liquids is only possible with the rotational viscometer. Viscosity measurements are carried out predominantly according to five methods: the capillary viscometer, the flow cup, the rotational viscometer, the rolling ball viscometer and the drawing ball viscometer. Each determination of viscosity should preferably be made at a temperature of 20°C and at one other temperature approximately 20°C higher. At least two determinations should be made at each temperature. The evaluation of the viscosity measurement is to be carried out according to the standards in the case of capillary and forced ball viscometers. In the case of rotational viscometers, the specification of a viscosity is appropriate only for Newtonian fluids. For non- Newtonian fluids the results obtained are preferred in the form of flow curves which must be interpreted, assuming the validity of various laws of flow.
This study relates to the analysis, via dermal application, of the health hazards of solid or liquid test substance. It may be carried out after initial information obtained by acute testing.
This method is composed of the main test and the limit test. This Test Guideline is intended for use with the adult rat, rabbit or guinea pig. At least 20 animals (10 female and 10 male) with healthy skin should be used at each dose level (at least three). The highest dose level should result in toxic effects but not produce an incidence of fatalities. The limit test corresponds to one dose level of at least 1000 mg/kg body weight. The method is based on the repeated application of the substance of interest during one limited period (several hours daily during 90 days). The test substance should be applied over not less than 10 per cent of the body surface area. The results of this study include: measurements and daily and detailed observations (ophthalmological examination, haematology, clinical biochemistry and urinalysis), as well as gross necropsy and histopathology. A properly conducted subchronic test should provide a satisfactory estimation of a non effect level.
This Test Guideline describes the methods allowing the determination of the dissociation constants in water. The dissociation is the reversible splitting into two or more chemical species which may be ionic.
The determination of the dissociation constant requires a measure of the concentrations of the dissociated and undissociated forms of the chemical substance. From a knowledge of the stoichiometry of the dissociation reaction the appropriate constant can be determined. In the particular case described in this Guideline the substance is behaving as an acid or a base, and the determination is most conveniently done by determining the relative concentrations of ionised and unionised forms of the substance and the pH of the solution. The relationship between these terms is given in the equation for pKa. Some compounds exhibit more than one dissociation constant. Some of the methods described are also suitable for non-acid/base dissociation. There are two basic approaches to the determination of pKa. One involves titrating a known amount of substance with standard acid or base, as appropriate; the other involves determining the relative concentrations of the ionised and unionised forms and their pH dependence. Methods based on those principles may be classified as titration, spectrophotometric and conductometric procedures.
This Test Guideline describes two methods. These tests are applicable only to water insoluble (solubility < 10-6 g/1) substances.
The first method described (Method A) is designed to provide information on the transportation and sedimentation of insoluble particles in water and air. There are several standard methods available which meet the sensitivity requirements: the sedimentation, the centrifugation or the coulter counter. The sample should be subjected to a simple light microscopic examination to determine the approximate nature of the particles. Data are obtained for a 3 size ranges ›200µm, ‹2 µm and the region 2to 200µm. Method A, which determines the effective hydrodynamic radius, Rs (only in the range 2 μm < Rs < 100 μm), can be used for both fibrous and non-fibrous particulates.
The Method B is used in the special case of materials which can form fibres, it is comparatively specialised, infrequently required and involves microscopic examination. Scanning (SEM) or transmission (TEM) electron microscopy are required. There is no standard procedure at present. The full length (l) and diameter (d) data are needed on fibre of dimensions d≥ 0.1µm and l≥ 5µm. Two histograms should be prepared based on examination of at least 50 fibres each.
This Test Guideline describes a method to determine the fat solubility of solid and liquid substances. The fat solubility of a substance is one of the data for evaluating the storage of lipid soluble materials in biological tissue.
This test method can only be applied to pure substances, non-reactive with triglyceride, which are stable at 50°C for at least 24 hours and which also are not appreciably volatile under the same conditions. The substance is dissolved in a liquid "standard fat" by stirring, and the saturation mass fraction of the substance is achieved by continued addition until a constant value for the mass fraction dependent variable is achieved as determined by a suitable analytical method.The methods use eight samples; each should be twice the quantity necessary for saturation as determined in the preliminary test. After adding a weighed amount of approximately 25 g of liquified and mixed standard fat, four flasks are stirred at 30°C (group I) and the other four at approximately 50°C (group II), each for at least one hour. All the flasks are stirred at 37°C, for liquids during 3 hours for two flasks of each group and for at least 24 hours for the last two flasks. At the end a sample is taken, weighed and the mass fraction is determined with different methods (photometric methods, gas chromatography, and extraction).
This Test Guideline describes a method which is an adaptation of the Soap and Detergent Association semi-continuous activated sludge (SCAS) procedure for assessing the primary biodegradation of alkyl benzene sulphonate. The test does not simulate those conditions experienced in a sewage treatment plant.
Activated sludge from a sewage treatment plant is placed in an aeration (SCAS) unit. The test compound (non-volatile, water soluble, organic, non-inhibitoring to bacteria at the test concentration) and settled domestic sewage are added, and the mixture is aerated for 23 hours. The aeration is then stopped, the sludge allowed to settle and the supernatant liquor is removed. The sludge remaining in the aeration chamber is then mixed with a further aliquot of test compound and sewage and the cycle is repeated. The above fill and draw procedure is repeated daily throughout the test. A high concentration of aerobic micro-organisms is used. The length of the test for compounds showing little or no biodegradation is indeterminate, but experience suggests that this should be at least 12 weeks. Biodegradation is established by determination of the dissolved organic carbon content of the supernatant liquor. This value is compared with that found for the liquor obtained from a control tube dosed with settled sewage only.
This Test Guideline describes methods for determining storage stability of a substance with respect to heat and air. Two methods are applicable to homogeneous solid and liquid substances and to mixtures of these: the accelerated storage test and the thermal analysis methods.
In the accelerated storage test (CIPAC), a long duration storage instability can be simulated by applying a higher temperature during a short test. This test calls for the controlled storage at 54°C to 55°C for 14 days and subsequent analysis. In simple cases, it will be enough to determine a characteristic property before and after storage. The substance is considered to be stable at room temperature if the melting point has remained constant or the content of original substance as determined by analysis has decreased by not more than 5 per cent.In the thermal analysis methods (TGA and DTA), the sample and the standard reference material are heated up to the final temperature at a constant rate in a defined test atmosphere, either separately in a TGA or DTA apparatus, or in a combined system. The weight change of the sample or the quantities of heat absorbed or given off are measured and recorded. The substance is considered to be stable at room temperature if no decomposition or chemical transformation is found below 150°.
This Test Guideline describes the determining of the ultraviolet-visible (UV-VIS) absorption spectrum of a chemical compound to have some indication of the wavelengths at which the compounds may be susceptible to photochemical degradation. Degradation will depend upon the total energy absorbed in specific wavelength regions. The absence of measurable absorption does not preclude the possibility of photodegradation. This method utilises a double-beam spectrophotometer which records only the absorption differences between the blank (the solvent and all present chemical species other than the test chemical) and test solutions to give the spectrum of the chemical being tested. The test should be carried out at 25°C. The test solutions should be made up in a concentration which will result in at least one absorbance maximum in the range 0.5 to 1.5 units.
The method described in this Test Guideline is designed for the evaluation of the mineralisation rate of a 14C-labelled compound in soil. The method is applicable to volatile or non-volatile, soluble or insoluble compounds which are not inhibitory to micro-organisms.
The basic test consists on the treatment of a small sample of soil (50g) with the 14C-labelled test chemical (100µl) in a biometer flask apparatus. The soil and the radioactive test solution are mixed. In addition, an equivalent volume of test solution is placed in a 100 ml volumetric flask for direct determination of the added radioactivity. The biometer flask is closed with a stopper through which an Ascarite filter is inserted. The unit is charged by injecting 10 ml of alkali solution into the side tube. Experiment duration times of 1, 2, 4, 8, 16, 32 and - if necessary - 64 days should be chosen for measurement. The test requires parallel determinations. The method can included optional experiments: for chemicals of a vapour pressure higher than 0.0133 Pa and for relatively persistent chemicals. Release of 14CO2 from the test chemical is measured by means of alkali absorption and liquid scintillation counting. The 14CO2 radioactivity recovered is plotted versus time. Incubation time is sufficient when a total of 50 per cent CO2 expressed as 14C originally applied can be measured. Incubation should be stopped after reaching 64 days, whether or not this value is obtained.
This study relates to the analysis, via dermal application, of the health hazard of solid or liquid test substance.
This method is composed of two tests: the main test and the limit test. This Test Guideline is intended for use with the adult rat, rabbit or guinea pig. At least 10 animals (5 female and 5 male) with healthy skin should be used at each dose level (at least three). The highest dose level should result in toxic effects but not produce an incidence of fatalities. The limit test corresponds to one dose level of at least 1000 mg/kg body weight. The method is based on the repeated application of the substance of interest during one limited period (several hours daily during 21/28 days). The test substance should be applied over not less than 10 per cent of the body surface area. The results of this study include: measurements and daily and detailed observations (haematology, clinical biochemistry and urinalysis), as well as gross necropsy and histopathology. A properly conducted 21-day or 28-day study should provide information on the effects of repeated inhalation exposure and can indicate the need for further longer term studies and provide information on the dose levels of the latter.
This Test Guideline describes the polarographic method. The ability of a substance to form complexes with metals can be assessed by means of polarographic techniques which allow the determination of stability constants for some complexes.
The polarographic method can be applied to substances with a water solubility greater than 10-5 M. This method is based on the fact that the reduction potentials of metal ions are shifted, usually to more negative values, as a result of complex formation. A minimum of four known concentrations of the chemical being tested should be investigated with a known concentration of metal ions. The chemical being tested should normally be present in at least a 25-fold excess over the metal ion concentrations. The current should be measured at applied potentials in the range - 0.2 V to -1.0 V. In order to detect complexes which form slowly, it is necessary to allow the solutions to stand under a nitrogen atmosphere for a minimum period of 24 hours. If the results are not significant, it is necessary to use methods based on different physicochemical principles, such as spectrophotometry or nuclear magnetic resonance spectrometry.
Transport and telecommunications are complementary technologies, essential to the functioning of the economic and social system, which facilitate the making and development of relationships. But as means of communication they also compete. The recent development of telecommunications constitutes a challenge to the transport sector. This report sets out to identify the nature and scope of that challenge.