Lexikon

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.

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 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

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

see Earth crust

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.

http://ec.europa.eu/taxation_customs/common/glossary/
customs/index_en.htm#C

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

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.

Chemical Name: 2-cyano-N-[(ethylamino)carbonyl]-2-(methoxyimino) acetamide
Common Name: Cymoxanil
Trade Name: Curzate 60 DF
Chemical Abstracts Service (CAS) Number: 57966-95-7
Pesticide Type: Fungicide

Cymoxanil is applied as a seed treatment to cut potato seed pieces or as a foliar application to the plants to control late blight (Phytophthora infestans). The end-use product, Curate 60 DF is formulated as a 60% dry flowable formulation. Curate 60 DF is to be used only in combination (tank mixed) with other protectant fungicides such as mancozeb, chlorothalonil, triphenyltin hydroxide, or metiram. As a seed treatment, the product is applied by dipping the 2 seed pieces in a concentrated slurry or by mist seed treating equipment.

Acute Toxicity: The acute toxicity data show that this chemical is not acutely toxic by the oral, inhalation, and dermal routes of exposure.
Subchronic Toxicity: In a subchronic oral study in mice, the NOEL was 8.25 mg/kg/day for males and 11.3 mg/kg/day for females. In a subchronic oral toxicity in dogs, a NOEL was not established and the LOEL was 3 mg/kg/day. In a subchronic oral toxicity/neurotoxicity study in rats, the NOEL was 47.6 mg/kg/day in males and 59.9 mg/kg/day for females. In a 28 day dermal toxicity study, the NOEL was 1000 mg/kg/day (highest dose tested).
Chronic Toxicity: In a combined chronic/carcinogenicity study, the NOEL was 4.08 mg/kg/day for males and 5.36 mg/kg/day of females. In a chronic toxicity study in dogs, the NOEL was 5.7 mg/kg/day for males and 3.1 mg/kg/day for females.
Carcinogenicity: Cymoxanil showed no evidence of carcinogenic potential and was classified as a “Not Likely” carcinogen.
Developmental Toxicity: In a prenatal developmental toxicity study in rats, the maternal and developmental NOEL was 10 mg/kg/day. In a prenatal developmental toxicity study in rabbits, the maternal and developmental NOEL was 16 mg/kg/day. In another prenatal developmental toxicity study in rabbits, the maternal and developmental NOEL was 4 mg/kg/day.
Reproductive Toxicity: In a two-generation reproduction study in rats, the parental systemic NOEL was 100 ppm (6.5 mg/kg/day for males and 7.9 mg/kg/day for females) and the offspring NOEL was 100 ppm.
Neurotoxicity: In the neurotoxicity portion of the subchronic/neurotoxicity study in rats, the NOEL for neurotoxicity was 224 mg/kg/day for males and 333 mg/kg/day for females. In the combined chronic toxicity/carcinogenicity study in rats, sciatic nerve axon/myelin degeneration was reported in females at dose levels of 30.3 and 90.1 mg/kg/day and hyperactivity and aggressiveness were reported in males at 30.3 and 90.1 mg/kg/day. In the carcinogenicity study in mice, absolute brain weight was decreased in both sexes at 216/298 mg/kg/day and 446/582 mg/kg/day for males/females. No evidence of developmental anomalies of the fetal nervous system were observed in the prenatal developmental toxicity studies in either rats, or rabbits, at maternally toxic oral doses up to 25 and 32 mg/kg/day. In addition, there was no evidence of behavioral or neurological effects on the offspring in the two-generation reproduction study in rats.
Mutagenicity: Gene mutation assays in bacterial and mammalian cells, a mouse micronucleus assay and an in vivo/in vitro unscheduled DNA synthesis (UDS) assay in rats were negative. An in vitro unscheduled DNA synthesis assay-primary rat hepatocytes and a chromosome aberrations in human lymphocytes assay were positive. However, the negative results from the mouse bone marrow micronucleus assay support the lack of carcinogenic effect in the rat and mouse longterm feeding study.

Reference Dose: The Reference Dose (RfD) for cymoxanil is 0.013 mg/kg/day. This value is based on the NOEL of 4.08 mg/kg/day from a chronic feeding study in rats. The Uncertainty Factor of 300 was used to account for interspecies extrapolation, intraspecies variation and the enhanced sensitivity of infants and children.

Classified based on the Globally Harmonised System (GHS):

• Acute Tox 4, H302
• Skin Sens 1A, H317
• STOT RE Cat 2, H373
• Repr. Cat 2, H361d
• Aquatic Acute 1, H400, M=1
• Aquatic Chronic 2, H411

Source: http://www.epa.gov/opprd001/factsheets/cymoxanil.pdf

it is a risk based target concentration for contaminated sites and contaminates soils. The Hungarian low requires the calculation of this target concentration in the remedial plan. The D-value is land-use specific.

see 1999/45/EC directive on classification, packaging, labelling of dangerous preparations
2001/59/EC directive on classification, packaging and labelling
67/548/EEC directive on classification, packaging and labelling

The Dangerous Substances Directive (as amended) is one of the main European Union laws concerning chemical safety. It was made under Article 100 (Art. 94 in a consolidated version ) of the Treaty of Rome. By agreement it is also applicable in the EEA, and compliance with the Directive will ensure compliance with the relevant Swiss laws.

The Directive applies to pure chemicals and to mixtures of chemicals (preparations) that are placed on the market in the European Union, therefore it does not apply directly to substances created purely for research purposes. Additional rules concerning preparations are contained in the Dangerous Preparations Directive (1999/45/EC) , these are very similar to the rules contained in the Dangerous Substances Directive 67/548/EEC.

Art. 2 of the Directive lists the classes of substances or preparations that are considered to be dangerous. Some, but not all, of these classes are associated with a chemical hazard symbols and/or a code.

• Explosives (E)
• Oxidizers agents (O)
• Flammable flammable substances or preparations, classified as extremely flammable (F+), highly flammable (F)
• Toxic substances or preparations, classified as very toxic (T+) or toxic (T)
• Harmful substances or preparations (Xn)
• Corrosive substances or preparations (C)
• Irritants (Xi)
• Sensitizers
• Carcinogens (Carc.), classified into three categories
• Mutagenic (Mut.), classified into three categories
• Substances or preparations that are reprotoxic (toxic for reproduction) (Repr.), classified into three categories
• Substances or preparations that are dangerous for the environment (N)

Substances or preparations falling into one or more of these classes are listed in Annex I of the Directive, which is regularly updated. A public database of substances listed in Annex I of the Directive is maintained by the Institute for Health and Consumer Protection.

The Directive does not apply to the following groups of substances and preparations (Art. 1):

• Medicines
• Cosmetics, which are covered by the Cosmetics Directive
• Waste
• Foodstuffs for humans or animals
• Pesticides
• Radioactive materials

The Directive does not apply to the transport of dangerous substances or preparations.

The danger symbols are defined in Annex II of the directive. A consolidated list with translations into other EU languages can be found in Directive 2001/59/EC.

The standard phrases are defined in Annexes III and IV of the Directive. Annex III defines phrases relating to the Nature of special risks attributed to dangerous substances and preparations, often referred to as R-phrases (R-phrases). Annex IV defines phrases relating to Safety advice concerning dangerous substances and preparations, often referred to as S-phrases (S-phrases).

The appropriate standard phrases must appear on the packaging and label of the product and on its MSDS. Annex I specifies the standard phrases to be used for substances that are listed there: these are obligatory.

The lists of standard phrases were last updated in 2001, and Directive 2001/59/EC provides a consolidated list in all EU languages.

Labelling: (Arts. 23-25). In general, the label on the packaging of a dangerous substance or preparation must clearly indicate the following items: the name of the substance; (for substances listed in Annex I, the name indicated must be one of those listed in the Annex (many substances appear in the Annex under different synonyms): otherwise, the name should be "internationally recognized")

Art. 27 of the Directive imposes an obligation on suppliers to provide an MSDS, on paper or electronically, at or before the first delivery of a dangerous substance or preparation. The supplier is also obliged to inform users of any relevant new information which becomes known. Directive 2001/58/EC provides detailed guidance for the preparation of material safety data sheets.

• the name, full address and telephone number of the person or company which has placed the substance on the market (manufacturer, importer or distributor);
• the danger symbols, if any;
• the standard phrases, if any; (certain exemptions are permitted)
• the EINECS number or equivalent;
• for substances listed in Annex I, the words EEC label.

http://en.wikipedia.org/wiki/Dangerous_Substances_Directive_%2867/548/EEC%29

Data Quality Objectives (DQO) are qualitative and quantitative statements derived from the DQO process describing the decision rules and the uncertainties of the decision(s) within the context of the problem(s).

DQO process is a quality management tool that enables planners to focus their planning efforts by specifying the use of the data (the decision), the decision criteria (action level) and the decision maker’s acceptable decision error rates. The products of the DQO process are the DQOs.

German Society for Chemical Engineering and Biotechnology is a non-profit scientific and technical society based in Frankfurt am Main, Germany. It has more than 5,500 private and institutional members, among them scientists, engineers, companies, organisations and institutes.

One aim of DECHEMA is to promote and support research and technological progress in Chemical Technology and Biotechnology DECHEMA regards itself as interface between science, economy, state and public.

a unit used to express relative difference on power, usually between acoustic or electric signals, equal to ten times the common logarithm of the ratio of the two level.

Read more:

http://www.animations.physics.unsw.edu.au/jw/dB.htm

a disease or an injury that happens as a result of exposures that might have occurred in the past.

for non-threshold effects, the underlying assumption is that a no-effect-level cannot be established and a DMEL therefore expresses an exposure level corresponding to a low, possibly theoretical, risk, which should be seen as a tolerable risk. (Source: REACH Glossary)

is the production of irreversible damage of the skin; namely, visible necrosis through the epidermis and into the dermis, following the application of a test substance for up to four hours. Corrosive reactions are typified by ulcers, bleeding, bloody scabs, and, by the end of observation at 14 days, by discoloration due to blanching of the skin, complete areas of alopecia, and scars. Histopathology should be considered to evaluate questionable lesions.

desertification means land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors, including climatic variations and human activities;

Combating desertification includes activities which are part of the integrated development of land in arid, semi-arid and dry sub-humid areas for sustainable development which are aimed at:

• prevention and/or reduction of land degradation;
• rehabilitation of partly degraded land;
• reclamation of desertified land.

UNCCD, the United Nations Convention to Combat Desertification in Countries Experiencing Serious Drought and/or Desertification, Particularly in Africa joins forces and actions all over the world.

See also: http://www.unccd.int/convention/text/convention.php

the lowest concentration of a chemical that can reliably be distinguished from a zero concentration.

in analytical chemistry, the detection limit is the lower limit of detection, or LOD (limit of detection), is the lowest quantity of a substance that can be distinguished from the absence of that substance (a blank value) within a stated confidence limit (generally 1%). The detection limit is estimated from the mean of the blank, the standard deviation of the blank and some confidence factor. Another consideration that affects the detection limit is the accuracy of the model used to predict concentration from the raw analytical signal.

There are a number of different "detection limits" that are commonly used. These include the instrument detection limit (IDL), the method detection limit (MDL), the practical quantification limit (PQL), and the limit of quantification (LOQ). Even when the same terminology is used, there can be differences in the LOD according to nuances of what definition is used and what type of noise contributes to the measurement and calibration.

Source: http://en.wikipedia.org/wiki/Detection_limit