Substance properties

As mentioned above, there are characterization factors for a number of different impact categories, e.g. acidification, eutrophication, climate change, human toxicity and ecotoxicity. However, characterization factors are missing for many additives, especially for human toxicity and ecotoxicity, which makes it difficult to assess the potential impact that a product will cause during its entire life cycle. A major reason that characterization factors are often missing is the lack of data regarding substance properties, such as physical chemical properties and toxicity. 

When a solid is in liquid solution it behaves according to its liquid state properties because it is in a liquid mixture. When applying Raoult s Law or similar expressions, the pure substance property is that of the liquid. Liquids such as crude oils and PCB mixtures consist largely of solid substances, but they are in the liquid state and generally unable to precipitate as solid crystals because of their low individual concentrations. 

Chemical Substances Properties Toxicology Ecotoxicology Underway (R=Recommended)... 

Depending on the drug substance properties and the medical indication, the appropriate formulation is chosen. Drug substances which have a good solubility may be formulated in a simple tablet formulation, while drug substance candidates with low solubilities require special delivery systems like microemulsion formulations. 

The systematic evaluation of substance properties and predictable or actual exposure patterns over the entire life-time of a substance within the scope of risk assessment is as yet a relatively recent instrument, for which harmonised scientific rales were created in the EU for the first time in 1997 in the form of the Technical Guidance Documents (TGD). An essential element in this range of instruments is how to deal with shortcomings in knowledge. Wherever information is missing, standardised worst-case scenarios are conceived taking into account appropriate safety factors . If under these worst-case assumptions a rele-... 

BASF is thus currently endeavouring to establish the substance DINCH as a new registered substitute (entirely tested plasticiser without any hazardous properties) for DEHP in high-price market segments (e.g. medical devices). Soft PVC users substitute on the material level, if they can achieve further process-related and/or quahty-related optimisations in the course of technological development (e.g. underbody hard shells) Environment and health-compatible substance properties are additional qualities in business-to-business (B2B) markets. They are of relevance almost only for manufacturers, who market their products on demand-dominated, saturated markets with differentiated quality production — Hypothesis 8). 

The rational characterisation of risks requites iterative evaluation processes in different stages on the basis of easily available information (preliminary processes, screening). The step-by-step consolidation of information about substance properties and exposnre potential should be made depending on the risk involved in order to concentrate the required resources for information procurement and evalnation where the essential risks are located (proceduralisation 2). 

Corporate management systems in the areas of environmental protection, employee protection and consumer protection should be integrated further to avoid a shift in risks and also to save costs. All areas require reliable and systematic data about substance properties and application-related exposure. Mechanisms are also required for effective dialogue along the supply chain as well as between companies and authorities. In addition, the comparative assessment of chemical products (for example, in purchasing or in product development) can only be done intelligently if all essential risk areas are included in the evaluation. 

Despite its age, Lyman s Handbook is still a valuable source of basic information on chemical properties, and many of the estimation methods contained therein remain valid. It also contains a suite of chapters on pure substance properties that normally are not of direct interest to environmental scientists e.g., flash point and heat capacity. 

Relatively low productivity can be expected when fines are produced by salting-out process although it also depends on the substance properties. The post-crystallization processing (separation, concentration etc.) of very weak slurries may go according to the routines of colloid chemistry practice. 

Can (Q)SAR be of help to address lack of data on substance properties and toxicity ... 

TABLE 5.2 Drug Substance Properties that are Important in the Selection of Manufacturing Platforms... 

Oral dmg product formulation and manufacturing process development can use a hierarchical approach to meeting three conditions based on, in order of importance, bioavailability, stability, and manufacturability. The bioavailability of a drug product is the most critical condition and must meet established criteria or the product is not viable. Dmg substance properties such as salt form, solubility, and particle size can significantly affect pharmacokinetic and pharmacodynamic performance of a product. The dosage form platform, formulation design, and manufacturing process can also affect the PK/PD profile of a product. Therefore, all selections must maintain the required pharmacokinetic/pharmacodynamic outcome and work within these confines to achieve a stable and robust product/process. 

Carcinogen/carcinogenic A substance/property of a substance that causes cancer when administered to an organism. 

Johansson compared several theoretical measures in order to find a theoretically calculable substance property which correlates to the oxidation potential of anions... 

From experience it is known which types of materials catalyze which reaction steps. It is desirable to relate their activity to solids properties which are measurable or which can be related to measurable quantities. In this way, it is possible to identify substance properties which are required for catalyst components or which should be avoided. 

Nyqvist, H. Influence of substance properties on scaling up of tablet formulations. Drug Dev. Ind. Pharm. 1989,15,957-964. 

Ointments utilize certain bases that act as vehicles to deliver the drug and to impart emollient and lubricant properties to the preparation. Usually, but not always, they contain medicinal substances. Properties of ointments may vary from product to product depending on their specific use, ease, and extent of application. In general, ointment bases may be classified into four general groups hydrocarbon, absorption, water-removable, and water-soluble bases. 

The above equation expresses the diffusion of vapor A through B medium, in which, Ma and Mb ate the molecular weight (kg/kmol), Po the absolute pressure, Oab and CIq are the molecule collision diameter and the molecule collision integral which are functions of substance properties and can be determined by empirical equations... 

Kersting, K. 1984. Development and use of an aquatic micro-ecosystem as a test system for toxic substances. Properties of an aquatic micro-ecosystem IV. Int. Rev. Hydrobiol. 69 567-607. 

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