Glossary

Benign by Design: An innovative concept in the framework of sustainable chemistry/pharmacy, which aims to design chemical substances and active pharmaceutical agents from the beginning in such a way that they optimally fulfil the set requirements regarding usage while minimising the resulting environment hazards as much as possible (benign). For example substances which could land in the aquatic environment are as completely and quickly biodegradable as possible.

 

Chemoinformatics, cheminformatics or chemistry informatics, computational chemistry: A branch of science, which connects the area of chemistry with methods of informatics with the goal of developing and using methods for the computation of properties of chemicals. Suitable algorithms are used to develop the coding for molecules. Induction can be used to create new hypotheses about molecular properties such as solubility, toxicity or degradability.

 

Health orientation value (HOV): The HOV is a precautionary value for substances which can either not be or only partially assessed from a human toxicological aspect. Its value is measured in such a way that a later, complete human toxicological evaluation of a non-genotoxic material/material with effectiveness threshold and the majority of genotoxic materials/materials without an effectiveness threshold securely leads to a lifelong hygienically tolerable or acceptable hygienic guide value at the level of the guide value of the HOV. For the lesser number of "strongly" genotoxic substances which can enter drinking water, the restriction of the HOV to a maximum exposure time of 10 years is recommended.

  • An HOV of 0.1 μg/l  serves as the first evaluation basis.
  • HOV ≤ 0.3 μg/l: The substance is demonstrably not genotoxic, i.e. in vitro primarily negative data about genotoxicity and/or the initial carcinogenic potential of the contaminant are present, otherwise no significant experimental toxicological data.
  • HOV ≤ 1 μg/l: The substance is demonstrably not genotoxic (see above). Significant in vitro and in vivo data about oral neuro-toxicity of the contaminant and its potential to harm germ cells are present. These data however do not refer to values below 0.3 μg/l.
  • HOV ≤ 3 μg/l: The substance is neither genotoxic nor harmful to germ cells or neurotoxic (see above). In addition significant in vivo data from at least one study of the subchronic oral toxicity of the contaminant are present. These data however do not refer to values below 1 μg/l.
    As a substitute the rating of the contaminants in the overall range >0,1 µg/l to 3 µg/l is then recommended, if scientifically appropriate resilient expectation statements about the relationship between structure and biochemical toxicological potential of the contaminants are present ("Structure/activity relationship",) see structureproperty relationship
  • From a hygienic aspect values > 3 μg/l can be permanently tolerated without further testing if at least one chronically oral study is present, on the basis of which the contaminants are toxicologically (almost) completely appraisable and the assessment does not refer to a value below 3 μg/l. Indications of this type for tentatively hygienically tolerable concentrations of non or only partially appraisable substances in drinking water above the HOV = 0.1 μg/l should however only be approved on a case by case basis by the German Federal Environmental Agency at a national level. (http://www.umweltbundesamt.de/wasser/themen/downloads/trinkwasser/Empfehlung-Nicht-bewertbare-Stoffe.pdf).

in vivo (lat.= in the living): Processes which take place in living organisms and are respectively investigated

 

in vitro: Processes, which in contrast to in vivo occur or are investigated outside of living organisms (e.g. in the reagent glass, in isolated cells)

 

in silico: Based on in vivo and in vitro, one designates processes which can be simulated with the computer as "in silico". The term is an allusion to the fact that most current computer chips are manufactured on the basis of the chemical element silicon.

 

Optimisation of chemical leads: By means of suitable chemical and biological hypotheses, the number of possible molecules which meet certain requirements can be reduced to a few most promising candidates, which are then synthesised in the laboratory and experimentally tested. For this reason chemistry informatics is playing an increasingly large role in the sector of pharmaceutical chemistry, but also in the environmental chemistry as well as the sustainable chemistry and the sustainable pharmacy for the optimisation of chemical leads (see also Benign by Design).

 

Molecular Modelling: Models of unknown structures are developed on the basis of known structures in order to enable a certain type of QSAR.

 

Sustainable chemistry/sustainable pharmacy/green pharmacy: Sustainable chemistry is the application of various methods within chemistry without burdening future generations. For this purpose techniques and technologies are developed and used, which get by with fewer raw materials and less energy, which maximize the use of renewable resources and minimise or completely eliminate the usage of hazardous chemicals. A further objective of sustainable chemistry and pharmacy is improved environmentally friendly products (see Benign by Design).

 

(Q)SAR ((Q)uantitative Structure-Activity Relationship): If structure property relationships are used for quantitative predictions, then one speaks of quantitative structure relationships. Often the term "structure activity relationship" (QSAR) is used in a broader sense that includes all physical, chemical, and biological properties of a chemical (see below). And sometimes one also finds the term Quantitative Structure Property Relationship (QSPR), if the relationship between the physical chemical properties of a molecule and its structure is involved.

 

REACH: The abbreviation REACH stands for "Registration, Evaluation and Authorisation of Chemicals". It affects manufacturers, importers and also users of chemicals. In the old ЕU legislation for the authorisation of chemical substances there were various rules for "old substances" (substances marketed before September 1981) and "new substances". Further information here.

 

Structure property relationship: A relationship between a pharmaceutical, chemical, biological, physical property of a molecule on the one hand and its chemical structure on the other hand. Such simple known relationships are reflected in the designations of chemical compounds with joint or similar properties such as alcohols, aldehydes, aromatic compounds, etc.


If structure property relationships are used for quantitative predictions, then one speaks of quantitative structure relationships. Sometimes one also finds the term Quantitative Structure Property Relationship (QSPR), if the relationship between the physical chemical properties of a molecule and its structure is involved.


These principles are widely used in the sector of active substance development and chemistry informatics. The first work in this area presumably took place already in 1842: A linear relationship between boiling points of alkanes with their chain lengths was established (temperature increase of 18 degrees per methyl group to be added).

© EDC Chemical Consulting | Sat, May 27th, 2017