Lexikon

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concentration-effect curve
condensation
confined water
conservation status of a natural habitat

conservation status of a natural habitat is the sum of the influences acting on a natural habitat and its typical species that may affect its long-term natural distribution, structure and functions as well as the long-term survival of its typical species within the territory referred to in Article 2. The conservative status of a natural habitat will be taken as "favourable" when its natural range and areas it covers within that range are stable or increasing, and the specific structure and functions which are necessary for its long-term maintenance exist and are likely to continue to exist for the foreseeable future, and the conservation status of its typical species is favourable as defined in 92/43.

Source: Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora.
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31992L0043:EN:html

conservation status of a species

conservation status of a species means the sum of the influences acting on the species concerned that may affect the long-term distribution and abundance of its populations within the territory referred to in Article 2;

The conservation status will be taken as "favourable" when:

- population dynamics data on the species concerned indicate that it is maintaining itself on a long-term basis as a viable component of its natural habitats, and

- the natural range of the species is neither being reduced nor is likely to be reduced for the foreseeable future, and

- there is, and will probably continue to be, a sufficiently large habitat to maintain its populations on a long-term basis.

Source: Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora.
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31992L0043:EN:html

Consotia under REACH

REACH requires that manufacturers/importers of the same substance cooperate jointly in preparing a submission, by sharing data and costs. Consortia are an efficient form of cooperation for potential registrants of a substance or group of substances to fulfil the REACH requirements in time.

ReachCentrum manages a large number of REACH consortia. ReachCentrum Consortium Management Services are designed for companies preparing, forming and operating REACH consortia. A good management practice is able to simplify the processes of forming and maintaining REACH consortia with the focus on meeting the REACH registration deadlines in time and cost efficiently.

constitution

a constitution is a set of fundamental principles according to which a state or other organization is governed.

Constitution and the Environment-relationship
Constitutional Court
construction noise or vibration source
contaminant hydrology
the study of the environmental fate and transport of antropogenic chemicals in groundwater (Source: EUGRIS)
contaminant, pollutant
contaminant-phase

separate liquid phase of a non-water-soluble organic contaminant in surface and subsurface waters, sediments and soils.

contaminants transformation in living organisms
contaminants uptake by living organisms
contaminated site
contaminated site risk
contamination limit value

treshhold concentration of chemical substances, which poses unacceptable risk in environmnetal compartment, food or cosmetics, etc. Limit values of environmental compartments depend on their use.

contamination of surface waters

contaminant concentration or level in the surface waters on the effect of discharge of contaminants or contaminating agents into surface waters.

content of environmental toxicity test standards
control sample

control sample is a sample with pre-determined characteristics which undergoes sample processing identical to that carried out for test samples and that is used as a basis for comparison with test samples. Examples of control samples include reference materials, spiked test samples, method blanks, dilution water (as used in toxicological testing), and control cultures (i.e., samples of known biological composition).

control site sample

control site sample, also known as “background sample”. These are samples of the media similar to the test sample matrix and are taken near to the time and place where the analytes of interest may exist at background levels. Usually the frequency of their analysis should be equivalent to that of the reagent blank. They are used to demonstrate whether the site is contaminated or truly different from the norm. Some sort of background sample is always necessary for a valid scientific comparison of samples suspected of containing environmental contaminants. Control site samples may further be differentiated as “local control site” and “area control sites” samples.

Copper (Cu)
CORINE Project
corrective action in environmental management

corrective action in environmental management means the process, when failure occurs, of investigation, correction and institution of preventative measures to preclude the recurrence of failure. An important component of corrective action is documentation of both problem and remedial measures taken.

corrosion
corrosion of metals

materially damaging, or even destroying metals by chemical action of a substance or a mixture. The corrosion resistance of metals and alloys is a basic property related to the easiness with which these materials react with a given environment.

Most common corrosion is a natural electrochemical process, that seeks to reduce the binding energy in metals. In the presence of oxigen the end result of corrosion involves a metal atom being oxidised, whereby it loses one or more electrons and leaves the bulk metal.

Corrosion of metals can be a chemical process or a biological process, as well as the combination of the two.

Some metals are more intrinsically resistant to corrosion than others, either due to the fundamental nature of the electrochemical processes involved or due to the details of how reaction products form. The materials most resistant to corrosion are those for which corrosion is thermodynamically unfavorable. Any corrosion products of gold or platinum tend to decompose spontaneously into pure metal, which is why these elements can be found in metallic form on Earth, and is a large part of their intrinsic value. Some metals have naturally slow reaction kinetics, even though their corrosion is thermodynamically favorable. These include such metals as zinc, magnesium, and cadmium: their corrosion is very slow. Metals, such as iron are very reactive, and corrosive in the presence of oxigen.

Microbial corrosion, is caused or promoted by microorganisms, usually chemoautotrophs. Sulfate-reducing bacteria are common in lack of oxygen; they produce hydrogen sulfide, causing sulfide stress cracking. In presence of oxygen, some bacteria directly oxidize iron to iron oxides and hydroxides, other bacteria oxidize sulfur and produce sulfuric acid causing biogenic sulfide corrosion. Concentration cells can form in the deposits of corrosion products, causing and enhancing galvanic corrosion.

The prevention of metals from corrosion may happen by passivation, coating, cathodic protection, or by using corrosion inhibitors, which are chemical compounds that, when added to a liquid or gas, decreases the corrosion rate of a metal or and alloy.

Indirectly biocides also are abel to prevent metal corrosion by killing the microorganisms responsible for it.

corrosive substances

a corrosive substance is one that will destroy or irreversibly damage another substance with which it comes in contact. The main hazards to people include damage to eyes, skin and tissue under the skin, but inhalation or ingestion of a corrosive substance can damage the respiratory and gastrointestinal tracts. A low concentration of a corrosive substance is usually an irritant. In the Globally Harmonized System (GHS) both rapid corrosion of metals and chemical corrosion of skin qualify for the "corrosive" symbol.
Common corrosive chemicals are classified into:
Acids, bases, dehydrating agents, strong oxidizers, electrophilic halogenes, organic halides and organic acid halides, acid anhydrides, alkylating agents, some organic materials, like phenol.
(Source: Wikipedia)

cosmetics

cosmetics and additives to cosmetics is an important group of chemicals substances because they directly effect human body, eye, skin or the metabolism, such as hormone and immune-system. The European Directive defines cosmetics as follows: a “cosmetic product” shall mean any substance or preparation intended to be placed in contact with the various external parts of the human body (epidermis, hair system, nails, lips and external genital organs) or with the teeth and the mucous membranes of the oral cavity with a view exclusively or mainly to cleaning them, perfuming them, changing their appearance and/or correcting body odors and/or protecting them or keeping them in good condition. The products to be considered as cosmetic products within the meaning of this definition are listed in Annex I of the Directive. Other Annexes enlist coloring agents, preservatives and UV -filters, which can be applied. Cosmetic products containing chemical substances hazardous for health should be excluded from marketing. The lists of these substances are also given in different Annexes of the Directive.

Source: Council Directive of 27 July 1976 on the approximation of the laws of the Member States relating to cosmetic products (76/768/EEC): http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CONSLEG:1976L0768:20080424:en:PDF

Cosmetics Directive 76/768/EEC

the European Directive defines cosmetics as follows: a “cosmetic product” shall mean any substance or preparation intended to be placed in contact with the various external parts of the human body (epidermis, hair system, nails, lips and
external genital organs) or with the teeth and the mucous membranes of the oral cavity with a view exclusively or mainly to cleaning them, perfuming them, changing their appearance and/or correcting body odours and/or protecting them or keeping them in good condition.
The products to be considered as cosmetic products within the meaning of this definition are listed in Annex I of the Directive. Other Annexes enlist colouring agents, preservatives and UV -filters, ehich can be applied.
Cosmetic products containing chemical substances hazardous for health should be excluded from marketing. The list of these substances are also given in different Annexes of the Directive.

Source: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CONSLEG:1976L0768:20080424:en:PDF

cosolvent
cost-benefit assessment
cost-efficiency assessment of environmenatl remediation
coulometry
determines the amount of analyte by measuring the amount of charge (current and time) required to complete reaction. It is named after C. A. Coulomb (1736-1806) French physicist who described the force between electric charges. The unity of charge is 1 coulomb, the amount of electric charge transported in 1 second by a steady state current of 1 ampere. There are two basic categories of coulometric techniques. Potentiostatic coulometry involves holding the electric potential constant during the reaction. The other, called coulometric titration or amperostatic coulometry, keeps the current (measured in amperes) constant. The methods are suitable for trace analysis. The most well known application is Karl Fischer titration for determination of water content and adsorbable organic halide content (AOX, EOX, POX). In these methods iodine and Ag+, respectively generated electrolytically are used for the titration.
Cr Chromium
cracker, IT
cracker, IT2
critical parameters of wastes, HU legislative term
critical review in LCA
crust
Crustacea
CSTEE

Comité Scientifique de Toxicologie, Ecotoxicologie et l'Environnement /European Scientific Committee on toxicity, ecotoxicity and Environment (http://ec.europa.eu/health/ph_risk/committees/sct/sct_en.htm)

One of the scientific committees of the European Union, dealing with scientific and technical questions relating to examination of the toxicity and ecotoxicity of chemical, biochemical and biological compounds whose use may have harmful consequences for human health and the environment.

cut-off rule, LCA
cyanobacteria
cyanocobalamin

cyanocobalamin is an especially common vitamer of the vitamin B12 family. It is chemically air-stable, easy to crystallize and therefore to purify after it is produced by bacterial fermentation. A form of B12 called hydroxocobalamin is produced by bacteria, and then changed to cyanocobalamin in the process of being purified in activated charcoal columns after being separated from the bacterial cultures. Cyanide is naturally present in activated charcoal, and hydroxocobalamin, which has great affinity for cyanide, picks it up and is changed to cyanocobalamin. Thus, the cyanocobalamin form of B12 is the most widespread in the food industry.

This fact has caused some people (usually from reading labels on packages and vitamin supplements, in which vitamin B12 is almost always listed last, since ingredients by law are listed in order of weight percentage), to infer that the correct chemical name of vitamin B12 actually is cyanocobalamin. In fact, vitamin B12 is the name for a whole class of chemicals with B12 activity, and cyanocobalamin is only one of these. Cyanocobalamin usually does not even occur in nature, and is not one of the forms of the vitamin which is directly used in the human body (or that of any other animal). However, animals and humans can convert cyanocobalamin to active (cofactor) forms of the vitamin, such as methylcobalamin. This process happens by equilibration, as cyanocobalamin slowly loses its cyanide in surroundings that contain no cyanide.

Cyanocobalamin is usually prescribed for the following reasons: after surgical removal of part, or all of the stomach or intestine to ensure there are adequate levels of vitamin B12 in the bloodstream; to treat pernicious anemia; vitamin B12 deficiency due to low intake from food; thyrotoxicosis, hemorrhage, malignancy, liver or kidney disease. Cyanocobamide is also used to perform the Schilling test to check a person's ability to absorb vitamin B12.

 

Sourece: Wikipedia

cycloalkane
a class of alkanes, saturated hydrocarbons that are in the form of a ring. For example, cyclohexane consists of a ring of 6 carbon atoms coupled by single bonds (C6H12).
cyclodextrin

cyclodextrins are cyclic oligosacharides produced from starch. The most well known representatives are built up from 6, 7, or 8 glucopyranose units called alpha-, beta- and gamma-cyclodextrins. The hydroxyl groups located at the rim of the ring ensure good water solubility. The inner side of these ring-shaped molecules is rather hydrophobic resulting in inclusion complex forming ability: guest molecules of poor solubilitycan enter the cavity of the host cyclodextrins. The solubility of the poorly soluble guest molecules is usually improved by complex formation. This solubilizing effect can be observed especially for the cyclodextrin derivatives of high solubility, like hydroxypropyl cyclodextrin (HPBCD) and random methylated cyclodextrin (RAMEB). Both are produced on ton scale. Pharmaceutical excipients and food additives. They are non-toxic. The alpha- and gamma-cyclodextrins can be consumed without any restrictions, the acceptable daily intake (ADI) for beta-cyclodextrin is 0.5 mg/kg, that is a person of 50 kg can consume 25 mg a day. The environmental application of cyclodextrins is based on their complex forming ability towards most of the organic contaminants. For example, the contaminants having low solubility, high Kow and high sorption to the soil (that is low bioavailability) will show improved availability on the effect of cyclodextrin complexation. The efficiency of the remediation technologies especially that of the bioremediation technologies can be enhanced by cyclodextrins as additives. cyclodextrins, as environmentally friendly materials can substitute the harmful tensides.

Cyclodextrin Technology
abbreviated as CDT, a bioremediation technology utilizing cyclodextrin (more exactly random methylated beta-cyclodextrin) for improving the bioavailablitity of the organic contaminants e.g. hydrocarbons, PAHs, chlorinated aliphatic hydrocarbons, polychlorinated biphenyls (PCBs) in the soil. The time saving by the cyclodextrin-intensified bioremediation may compensate for the higher price of the technology. Further details can be found in MOKKA database (sheets No. 51 and 175). Further literature: Gruiz, K.; Fenyvesi, E.; Kriston, E.; Molnar, M.; Horvath, B. (1996) J. Inclusion Phenom. Mol. Recognit. Chem. 25(1-3), 233-236, Leitgib, L.; Gruiz, K.; Fenyvesi, E.; Balogh, G.; Muranyi, A. (2008) Science of the Total Environment, 392(1), 12-21