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classification and labelling of chemicals: short explanation

The CLP Regulation (Classification, Labelling and Packaging) ensures that the hazards presented by chemicals are clearly communicated to workers and consumers in the European Union through classification and labelling of chemicals.

Before placing chemicals on the market, the industry must establish the potential risks to human health and the environment of such substances and mixtures, classifying them in line with the identified hazards. The hazardous chemicals also have to be labelled according to a standardised system so that workers and consumers know about their effects before they handle them.

As a result of this process, the hazards of chemicals are communicated through standard statements and pictograms on labels and safety data sheets. For example, when a supplier identifies a substance as "acute toxicity category 1 (oral)", the labelling will include the hazard statement "fatal if swallowed", the word "Danger" and a pictogram with a skull and crossbones.

The CLP Regulation entered into force in January 2009, and the method of classifying and labelling chemicals it introduced is based on the United Nations' Globally Harmonised System (GHS).

The Regulation replaces over time two previous pieces of legislation, the Dangerous Substances Directive and the Dangerous Preparations Directive. There is a transition period until 2015.


Source: http://echa.europa.eu/web/guest/regulations/clp/understanding-clp

classification in LCA
classification of soil remediation technologies
classification, packaging, labelling, 1999/45/EC

1999/45/EC directive on classification, packaging, labellingis the Directive of the European Parliament and of the Council of 31 May 1999, concerning the approximation of the laws, regulations and administrative provisions of the Member States relating to the classification, packaging and labelling of dangerous preparations.

classisfication of chemical substances

classification is the process in which a given substance or preparation is assigned one of the 15 categories of danger depending on their intrinsic properties in accordance with the criteria for specified in directive 67/548/EEC. If the substance is not found to be dangerous, according to the said criteria, then it is not classified. Under GHS the substance or preparation will be assigned to hazard classes.

See also labelling of chemical substances and GHS.

(Source: REACH)


clay is a naturally occurring material composed primarily of fine-grained minerals, which show plasticity through a variable range of water content, and which can be hardened when dried and/or fired. Clay deposits are mostly composed of clay minerals phyllosilicate minerals, minerals which impart plasticity and harden when fired and/or dried, and variable amounts of water trapped in the mineral structure by polar attraction.

Clay minerals are typically formed over long periods of time by the gradual chemical weathering of silicate rocks.

Clays are distinguished from other fine-grained soils by their grain-size. The grain size of clay-minerals are close to the colloidal size-range. Geologists and soil scientists usually consider 2 µm and under, sedimentologists often use 4-5 μm and under, and colloid chemists use 1 μm border line. Geotechnical engineers measure the plasticity properties of the soil to indentify clay-content and its geotechnical consequences Atterberg limits. See also soil texture.

clay minerals

clay minerals are hydrous aluminium phyllosilicates, sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths and other cations. Clay minerals are common weathering products including weathering of feldspar and low temperature hydrothermal alteration products. Clay minerals are very common in fine grained sedimentary rocks such as shale, mudstone and siltstone and in fine grained metamorphic slate and phyllite.

Clays are ultra fine grained normally considered to be less than 2 micrometres in size on standard particle size classifications and so require special analytical techniques. Standards include x-ray diffraction, electron diffraction methods, various spectroscopic methods such as Mossbauer spectroscopy, infrared spectroscopy, and EDS or energy dispersive spectroscopy. These methods should always augment standard polarized light microscopy, a technique which is sometimes overlooked but often where fundamental occurrences or petrologic relationships are established.

Clays are fundamentally built of tetrahedral sheets and octahedral sheets. A 1:1 clay would consist of one tetrahedral sheet and one octahedral sheet, and examples would be kaolinite and serpentine. A 2:1 clay consists of an octahedral sheet sandwiched between two tetrahedral sheets, and examples are illite, smectite, attapulgite, and chlorite although chlorite has an external octahedral sheet often referred to as "brucite".

Clay minerals include the following groups:

  • Kaolin group which includes the minerals kaolinite, dickite, halloysite and nacrite. Some sources include the serpentine group due to structural similarities Bailey 1980.
    • Smectite group which includes dioctahedral smectites such as montmorillonite and nontronite and trioctahedral smectites for example saponite.
    • Illite group which includes the clay-micas. Illite is the only common mineral.
    • Chlorite group includes a wide variety of similar minerals with considerable chemical variation.
    • Other 2:1 clay types exist such as sepiolite or attapulgite, clays with long water channels internal to their structure.

    Mixed layer clay variations exist for most of the above groups. Clay minerals in soil have an important role in bonding both nutrients and pollutants.

    Sorce: Wikipedia, http://en.wikipedia.org/wiki/Clay_minerals

    clean matrix spike

    clean matrix spike is a sample with no detectable analyte concentration to which an analyte spike has been added.

    climate change

    the term "climate change" is used to imply a significant change from one climatic condition to another. Sometimes, climate change is used synonymously with the term global warming; scientists however tend to use the term in the wider sense to also include natural changes in climate.

    clinical toxicology

    clinical toxicology is concerned with diseases and illnesses associated with short term or long term exposure to toxic chemicals. Forensic toxicology is based on the cause and effect relationships between exposure to a drug or chemical substance and the toxic or lethal effects that result in.


    cloning is a in vitro DNA technology to produce multiple, exact copies of a single gene or other segment of DNA, even a whole genom to obtain enough material for further study or application.

    The resulting cloned (copied) collections of DNA molecules are called clone libraries.

    A second type of cloning exploits the natural process of cell division to make many copies of an entire cell, containing a gene or another segment of DNA or the whole genom.

    The genetic makeup of these cloned cells, called a cell line, is identical to the original cell.

    A third type of cloning produces complete, genetically identical organisms, microorganisms, plants or animals such as the famous Scottish sheep, Dolly.

    close space, noise
    closed airspace

    Clostridium is a genus of Gram-positive bacteria, belonging to the Firmicutes. They are obligate anaerobes capable of producing endospores. Individual cells are rod-shaped.

    There are four main species responsible for disease in humans:

    C. botulinum, an organism producing a toxin in food/wound that causes botulism. Honey sometimes contains spores of Clostridium botulinum, which may cause infant botulism in humans one year old and younger. The bacteria produce botulinum toxin, which eventually paralyzes the infant's breathing muscles. Adults and older children can eat honey safely, because the clostridia do not compete well with the other rapidly growing bacteria present in the gastrointestinal tract.

    C. difficile, can overgrow other bacteria in the gut during antibiotic therapy and cause pseudomembranous colitis.

    C. perfringens, formerly called C. welchii, causes a wide range of symptoms, from food poisoning to gas gangrene. Also responsible for enterotoxemia (also known as "overeating disease" or "pulpy kidney disease") in sheep and goats. C. perfringens also takes the place of yeast in the making of salt rising bread.

    C. tetani, the causative organism of tetanus.

    C. sordellii has been linked to the deaths of more than a dozen women after childbirth.

    Clostridium is sometimes found in raw swiftlet birds' nests, a Chinese delicacy. Nests are washed in a sulfite solution to kill the bacteria before being imported to the U.S.

    Neurotoxin production is the unifying feature of the species C. botulinum.

    As therapy, passive immunisation with human anti-tetanospasmin immunoglobulin or tetanus immunoglobulin is crucial. If specific anti-tetanospasmin immunoglobulin is not available, then normal human immunoglobulin may be given instead. All tetanus victims should be vaccinated against the disease or offered a booster shot.

    Many clostridium stains are utilised by industry and commerce.

    C. thermocellum can utilize lignocellulosic waste and generate ethanol, thus making it a possible candidate for use in ethanol production. It also has no oxygen requirement and is thermophilic, reducing cooling cost.

    C. acetobutylicum, also known as the Weizmann organism, was first used by Chaim Weizmann to produce acetone and biobutanol from starch in 1916 for the production of gunpowder and TNT.

    The anaerobic bacterium C. ljungdahlii, recently discovered in commercial chicken wastes, can produce ethanol from single-carbon sources including synthesis gas, a mixture of carbon monoxide and hydrogen that can be generated from the partial combustion of either fossil fuels or biomass. Use of these bacteria to produce ethanol from synthesis gas has progressed to the pilot plant stage at the BRI Energy facility in Fayetteville, Arkansas.

    Fatty acids are converted by yeasts to long-chain dicarboxylic acids and then to 1,3-propanediol using Clostridium diolis.

    Genes from C. thermocellum have been inserted into transgenic mice to allow the production of endoglucanase. The experiment was intended to learn more about how the digestive capacity of monogastric animals could be improved. Hall et al. published their findings in 1993.

    Non-pathogenic strains of clostridia may help in the treatment of diseases such as cancer. Research shows that clostridia can selectively target cancer cells. Some strains can enter and replicate within solid tumours. Clostridia could, therefore, be used to deliver therapeutic proteins to tumours. This use of Clostridia has been demonstrated in a variety of preclinical models.

    Source: Wikipedia

    CLP Regulation

    the CLP Regulation (for "Classification, Labelling and Packaging") is a European Union regulation which aligns the European Union system of classification, labelling and packaging chemical substances and mixtures to the Globally Harmonised System (GHS). It is expected to facilitate global trade and the harmonised communication of hazard information of chemicals and to promote regulatory efficiency. It complements the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) Regulation (EC No 1907/2006) and replaces the current system contained in the Dangerous Substances Directive (67/548/EEC)and the Dangerous Preparations Directive (1999/45/EC).

    1272/2008 regulation of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of substances and mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006.This Regulation says, that is should ensure a high level of protection of human health and the environment as well as the free movement of chemical substances, mixtures and certain specific articles, while enhancing competitiveness and innovation.

    The regulation incorporates the classification criteria and labelling rules agreed at UN level, the so called Globally Harmonised System of Classification and Labelling of Chemicals (GHS). It introduces new classification criteria, hazard symbols (pictograms) and labelling phrases, while taking account of elements which are part of the current EU legislation.

    The regulation requires companies to appropriately classify, label and package their substances and mixtures before placing them on the market. It aims to protect workers, consumers and the environment by means of labelling which reflects possible hazardous effects of a particular chemical. It also takes over provisions of the REACH Regulation regarding the notification of classifications, the establishment of a list of harmonised classifications and the creation of a classification and labelling inventory.

    Harmonised classification (legal classification) results from the inclusion into the list of substances in Annex VI of the CLP Regulation (formerly Annex I Directive 67/548/EEC).

    Full text of the regulation: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2008:353:0001:1355:EN:PDF

    Club of Rome

    it was founded in April 1968 and raised considerable public attention in 1972 with its report The Limits to Growth. The club states that its mission is "to act as a global catalyst for change through the identification and analysis of the crucial problems facing humanity and the communication of such problems to the most important public and private decision makers as well as to the general public." Since 1 July 2008, the organization has its headquarters in Winterthur, Switzerland.

    See also: http://en.wikipedia.org/wiki/Club_of_Rome


    chemical substances with carcinogenic, mutagenic or toxic effect to reproduction. The abbreviation of CMR is used for the characterisation of chemical substances with these properties. Consequences and obligations of being CMR are given by REACH.

    CMS, IT

    Content Management System

    co-metabolism based bioremediation
    co-metabolism, co-oxidation

    a black or brownish black solid, combustible carbon-rich substance formed by the partial decomposition of vegetable matter without access to air. Coal is one of the most important of the primary fossil fuels. It constitutes humankind’s main source of energy.

    coal tar

    coal tar and coal tar oil are principal liquid products resulting from the carbonisation of coal, what means the heating of coal in the absence of air at temperatures ranging from about 900º to 1,200ºC (1,650º to 2,200ºF). Many commercially important compounds are derived from coal tar, such as dyestuffs and pigments.

    coast protection
    coast protective waterwork
    coastal water

    urface water on the landward side of a line, every point of which is at a distance of one nautical mile on the seaward side from the nearest point of the baseline from which the breadth of territorial waters is measured, extending where appropriate up to the outer limit of transitional waters.

    coli bacterium
    colorimetric methods
    traditional methods for analysis of elements or compounds using specific reactions which give colored products. For instance, the Fe(II) ions give a pink colored complex with o-phenanthroline. The color intensity is proportional to the concentration of the element, compound to be measured. The colorimetric methods are very often used even nowadays although they lack the low detection limit characteristic of modern instrumental methods such as atomic absorption spectroscopy (AAS) and inductive coupled plasma mass spectrometry (ICP-MS)
    combined sewer system
    common flood-control works
    common technical specification

    common technical specification is a technical specification drawn up in accordance with a procedure recognized by the Member States with a view to uniform application in all Member States and published in the Official Journal of the European Communities.

    Source: Council Directive 93/38/EEC of 14 June 1993 coordinating the procurement procedures of entities operating in the water, energy, transport and telecommunications sectors.

    common wastewater treatment plant
    common water conveyance
    Competent Authority (CA)
    Mcompetent authority means the authority or authorities or bodies established by the Member States to carry out the obligations arising from REACH Regulation. (Source: REACH Glossary)
    Competent Authority (CA), REACH
    complex substances

    substance intentionally added to form a preparation (Source: REACH)

    component of chemicals

    under REACH "component" is an individual chemical substance in a mixture of chemicals or in a product.

    Source: REACH

    component, REACH

    substance intentionally added to form a preparation.

    (Source: REACH)

    composite sample

    composite sample is a combination of multiple individual samples taken at pre-selected times to represent the integrated composition of the wastewater being sampled. Usually all samples added to the composites are equal in size, but flow-proportional composite samples collect amounts proportional to flow.


    Composting as a recognized practice dates to at least the early Roman era since Pliny the Elder (AD 23-79) who refers to compost in his writings. Traditionally, composting was to pile organic materials until the next planting season, at which time the materials would be ready for soil application. The main advantage of this method is that little working time or effort is required from the composter and it fits in naturally with agricultural practices in temperate climates. Disadvantages (from the modern perspective) are that space is used for a whole year, some nutrients might be leached due to exposure to rainfall, and disease producing organisms, some weed, weed seeds and insects may not be adequately controlled.

    Composting was somewhat modernized beginning in the 1920s in Europe as a tool for organic farming.The first industrial station for the transformation of urban organic materials into compost was set up in Wels/Austria in the year 1921 The early personages most cited for propounding composting within farming are for the German-speaking world Rudolf Steiner, founder of a farming method called biodynamics, and Annie Francé-Harrar, who was appointed on behalf of the government in Mexico and supported the country 1950–1958 to set up a large humus organization in the fight against erosion and soil degradation. In the English-speaking world it was Sir Albert Howard who worked extensively in India on sustainable practices and Lady Eve Balfour who was a huge proponent of composting.

    There are many modern proponents of rapid composting which attempt to correct some of the perceived problems associated with traditional, slow composting. Many advocate that compost can be made in 2 to 3 weeks.Many such short processes involve a few changes to traditional methods, including smaller, more homogenized pieces in the compost, controlling carbon to nitrogen (CN) ratio at 30 to 1 or less, and monitoring the moisture level more carefully. However, none of these parameters differ significantly from early writings of Howard and Balfour, suggesting that in fact modern composting has not made significant advances over the traditional methods which take a few months to work. For this reason and others, many modern scientists who deal with carbon transformations are sceptical that there is a "super-charged" way to get nature to make compost rapidly. They also point to the fact that it is the structure of the natural molecules - such as carbohydrates, proteins, and cellulose - that really dictate the rate at which microbial-mediated transformations are possible.

    Sources: http://en.wikipedia.org/wiki/Compost

    computer virus