Lexikon

a virus for which the natural host is a bacterial cell.

pharmacokinetics or toxicokinetics is "defined as the study of the rates of absorption, distribution, metabolism, and excretion of toxic substances or substances under toxicological study" (OECD). Pharmacokinetics/toxicokinetics testing involves describing "the bioavailability of a substance and its kinetic and metabolic fate within the body". Pharmacokinetics is also the term used to describe the assessment of absorption, distribution and metabolism in the context of drug preclinical testing.

Metabolism has been "defined as all aspects of the fate of a substance in an organism ..." by OECD; however, metabolism generally refers to the biotransformation of a substance (via an enzymatic or nonenzymatic process) within the body to other molecular species (usually called the metabolites). For ingested substances, metabolism primarily takes place in the liver, although many organs and tissues have metabolic capability. Two types of enzymes are involved in metabolism: phase 1 (cytochrome P450 enzyme family) and phase 2 enzymes.

An understanding of the metabolism of a substance in the body is critical to understanding its toxicity. For example, biotransformation sometimes results in a molecular species being generated that is more toxic than the original substance. The lack of metabolism of a substance can result in its bioaccumulation in the body. Understanding a substance's metabolism can also facilitate identification of possible target organs and the route of clearance.

Pharmacokinetic/toxicokinetic data may be used to:

1. assist in the interpretation of other toxicological data,
2. select doses for other toxicological studies, and/or
3. extrapolate data from animals to the human (OECD).

Source: http://alttox.org/ttrc/toxicity-tests/pharmacokinetics-metabolism/

pharmacology is the closest related branch of applied science to human toxicology, which is the study of drug action. The methodology is very similar to human toxicity assessment, the difference is, that drugs are applied for their beneficial effects on human or other organisms, and the main effect has a special target (e.g. to kill pathogens or harmful cells, etc.). More specifically, pharmacology is the study of the interactions that occur between a living organism and the chemicals substance, the drug, that affect biochemical function. If the substances have medicinal properties, they are considered pharmaceuticals and the assessment is pharmacological assessment. If the drug is a toxicant, toxicology is dealing with its effects. As all drugs, even if they have a dose range, which leads to medicinal application, they are toxicants, it also underlines that the methodologies are very closely related, mainly the aim differentiates pharmacology from toxicology.

policyclic aromatic hydrocarbon, CAS No. 85-01-8

phenols, sometimes called phenolics, are a class of chemical compounds consisting of an -OH group attached to anaromatic benzene ring. The simplest of the class is phenol (C₆H₅OH).

phenols have unique properties and are not classified as alcohols (since the hydroxyl group is not bonded to a saturated carbon atom). They have relatively high acidity.
Some phenols are germicidal and are used in formulating disinfectants. Others possess endocrine disrupting activity.
Some others are biological active molecules with positive health effects, such as flavonoids and tannins, capsaicine or salicilic acid.

the physical characteristics of an organism or the presence of a disease that may or may not be genetic.

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phthalates, or phthalate esters, are esters of phthalic acid and are mainly used as plasticizers (substances added to plastics to increase their flexibility, transparency, durability, and longevity). They are used primarily to soften polyvinyl chloride. Phthalates are being phased out of many products in the United States, Canada, and European Union over health concerns.

DEHP has been the main “general purpose” phthalate used over the last 50 years. It has had applications in a wide range of soft-PVC and non-PVC polymer materials, these being further processed in the production of a range of indoor and outdoor products, both for industrial/professional and consumer uses. In addition to polymer applications DEHP has also been used in adhesives, sealants (which are often applied to windows and doors for improved insulation), rubber, lacquers, paints and printing
inks. Therefore, DEHP can be found in building and construction materials (e.g. in flooring, roofing, industrial doors, wires, cables, hoses and profiles), in coated fabrics (such as artificial leather for bags and automotive applications, book covers and bindings, maps and folders), in medical devices (e.g. blood bags, dialysis equipment) as well as in a multitude of other products such as traffic cones, buoys, curtains for lorries and train compartments, tarpaulins, signs, flexible containers, disposable gloves or dipped tool handles, sports mats, swimming pool covers, shower curtains, napkins, stationery films, water beds, furniture, luggage or shoe soles. It has also been reported to be used in primary packaging of medicinal products and active pharmaceutical substances (EU, 2008; ECHA, 2009; www.dehp-facts.com).

In October 2008, the low phthalates DEHP, DBP and BBP were included in the REACH “Candidate List” and in April 2009 ECHA proposed them for inclusion in the REACH Authorisation List (Annex XIV). The inclusion in the Authorisation List was confirmed officially in February 2011, with a phase-out date of February 2015 for these low phthalates unless they Authorised through submission of a dossier by manufacturers or users. Another low phthalate, DIBP, was proposed by Germany in September 2009 and was included on the REACH “Candidate List” in January 2010. As expected, these low phthalates were included on the list due to their EU hazardous classification. The full list of substances is available here.

In the case of low phthalates DEHP, DBP and BBP, they will have to undergo Authorisation. The main DEHP producer has already declared that they intend to seek Authorisation to ensure the continued availability of DEHP in the future.

The inclusion of DEHP, DBP, BBP and DIBP on the “candidate list” means that any EU manufacturer or importer of an article containing more than 0.1% weight by weight (w/w) of these phthalates must notify ECHA as of June 2011, unless the articles manufacturer or importer can clearly demonstate that their use has already been registered. In addition the article manufacturer or importer must now provide information to the recipient of that article. As a minimum, recipients – meaning anyone in the supply chain from distributors and retailers to professional end-users - need to be told that the article contains one or more of the substances. Further down the supply chain, retailers also have an obligation to provide the same information to consumers, but only if a consumer requests it. A retailer has 45 days to provide the information.

Six phtalates (DEHP, BBP, DINP, DIDP and DNOP) are under consideration to be restricted in Europe (under REACH) on the initiative of Denmark, who prepared a restriction dossier for phtalates and submitted it to ECHa (European Chemicals Agency).

Denmark submitted a dossier in May 2011, which proposes the restriction of bis(2-ethylhexyl) phthalate (DEHP), benzyl butyl phthalate (BBP), dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP) in articles that are for indoor use, or in articles that come into contact with skin or mucous membranes, on the grounds that they are classified as category 1B reprotoxins under the CLP Regulation (CW 21 May 2011(http://chemicalwatch.com/7262/danes-cite-combined-exposure-in-reach-phthalates-proposals).

High phthalates are not classified as PBT or vPvB substances. They do not fulfill the criteria to be considered Substances of Very High Concern (SVHC) and therefore are not included on the EU REACH Candidate List nor do they need Authorisation to be placed on the EU market.

Sources:

http://www.plasticisers.org/regulation/reach

http://reseau-environnement-sante.fr/wp-content/uploads/2011/06/Veille_phtalates_au_26-06-11.pdf

http://en.wikipedia.org/wiki/Phthalate

physical weathering is caused by the effects of changing temperature on rocks, causing the rock to break apart. The process is sometimes assisted by water.

There are two main types of physical weathering:

• Freeze-thaw occurs when water continually seeps into cracks, freezes and expands, eventually breaking the rock apart.
• Exfoliation occurs when minerals in the rocks are continuously heated and cooled in hot climates.
• On the effect of cristal-formation of salts or oxide formation of iron or other metals. Increased volume of these chemical componunds break the rock.
• Plnat root growth is able to break the rock too.

Physical weathering happens especially in places places where there is little soil and few plants grow, such as in mountain regions and hot deserts. Either through repeated melting and freezing of water (mountains and tundra) or through expansion and contraction of the surface layer of rocks that are baked by the sun (hot deserts).

hysico-chemical testing methods for chemical substances: COUNCIL REGULATION (EC) No 440/2008 of 30 May 2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).

(1) Pursuant to Regulation (EC) No 1907/2006, test methods are to be adopted at Community level for the purposes of tests on substances where such tests are required to generate information on intrinsic properties of substances.

(2) Council Directive 67/548/EEC of 27 June 1967 on the approximation of the laws, regulations and administrative provisions relating to the classification, packaging and labelling of dangerous substances laid down, in Annex V, methods for the determination of the physico-chemical properties, toxicity and ecotoxicity of substances and preparations. Annex V to Directive 67/548/EEC has been deleted by Directive 2006/121/EC of the European Parliament and of the Council with effect from 1 June 2008.

(3) The test methods contained in Annex V to Directive 67/ 548/EEC should be incorporated into this Regulation.

(4) This Regulation does not exclude the use of other test methods, provided that their use is in accordance with Article 13(3) of Regulation 1907/2006.

(5) The principles of replacement, reduction and refinement of the use of animals in procedures should be fully taken into account in the design of the test methods, in particular when appropriate validated methods become available to replace, reduce or refine animal testing.

(6) The provisions of this Regulation are in accordance with the opinion of the Committee established under Article 133 of Regulation (EC) No 1907/2006

Article 1: The test methods to be applied for the purposes of Regulation 1907/2006/EC are set out in the Annex to this Regulation.

Article 2: The Commission shall review, where appropriate, the test methods contained in this Regulation with a view to replacing, reducing or refining testing on vertebrate animals.

Article 3: All references to Annex V to Directive 67/548/EEC shall be construed as references to this Regulation.

Article 4: This Regulation shall enter into force on the day following its publication in the Official Journal of the European Union.

It shall apply from 1 June 2008.

LIST OF METHODS FOR THE DETERMINATION OF PHYSICO-CHEMICAL PROPERTIES OF CHEMICAL SUBSTANCES

A.1. Melting/freezing temperature
A.2. Boiling temperature
A.3. Relative density
A.4. Vapour pressure
A.5. Surface tension
A.6. Water solubility
A.8. Partition coefficient
A.9. Flash-point
A.10. Flammability (solids)
A.11. Flammability (gases)
A.12. Flammability (contact with water)
A.13. Pyrophoric properties of solids and liquids
A.14. Explosive properties
A.15. Auto-ignition temperature (liquids and gases)
A.16. Relative self-ignition temperature for solids
A.17. Oxidising properties (solids)
A.18. Number – average molecular weight and molecular weight distribution of Polymers
A.19. Low molecular weight content of polymers
A.20. Solution/extraction behaviour of polymers in water
A.21. Oxidising properties (liquids)

phytotechnology is broadly defined as the use of vegetation to address contaminants in soil, sediment, surface water, and groundwater. Cleanup objectives for phytotechnologies can be contaminant removal and destruction, control and containment, or both. Phytoremediation (i.e., contaminant removal and destruction) is a phytotechnology subset (ITRC 2009).

While phytotechnologies generally are applied in situ, ex situ applications (e.g., hydroponics systems) are possible. Typical organic contaminants, such as petroleum hydrocarbons, gas condensates, crude oil, chlorinated compounds, pesticides, and explosive compounds, can be addressed using plant-based methods. Phytotechnologies also can be applied to typical inorganic contaminants, such as heavy metals, metalloids, radioactive materials, and salts (ITRC 2009).

Six major plant mechanisms enable phytotechnologies to remove, destroy, transfer, stabilize, or contain contaminants:

1.Phytoextraction

Phytoextraction involves contaminant uptake by plant roots, with subsequent accumulation in plant tissue. Plants that accumulate contaminants may require periodic harvesting and proper disposal to avoid recontaminating the soil when the plants die or drop their leaves. Phytoextraction typically is used to address inorganic contaminants, such as metals, metalloids, and radionuclides. Organic contaminants are more likely to be transformed rather than accumulated within the plant tissue. Successful field applications of phytoextraction to take up metals have been limited; however, promising research is underway for using phytoextraction on mercury and persistent organic pollutants (USEPA 2006).

Pesticides classified as persistent organic pollutants resist biodegradation and can remain in the environment for decades. Scientists have identified plants that are capable of extracting chemicals, such as chlordane and 2,2-bis(p-chlorophenyl)1,1-dichloroethene (p,p'-DDE), and storing them in their roots, leaves, and fruits (USEPA 2006).

Plants used in phytoextraction (e.g., Indian mustard, Alpine pennycress, sunflowers, ferns, grasses) typically are effective only in the top one foot of soil because of their shallow root systems and generally slow growth. Researchers are working on genetic modifications that increase the survivability of plants that hyperaccumulate toxic contaminants (USEPA 2006).

2. Phytodegradation

Like phytoextraction, phytodegradation involves the uptake of contaminants; however, metabolic processes within the plant subsequently break down the contaminants. Phytodegradation also encompasses the breakdown of contaminants in the soil through the effects of enzymes and other compounds produced by plant tissues other than the roots (USEPA 2006).

Phytodegradation is applicable to organic contaminants. Their uptake is affected by their hydrophobicity, solubility, and polarity; moderately hydrophobic and polar compounds are more likely to be taken up after sorbing to plant roots. Chlorinated solvents, herbicides, insecticides, pentachlorophenol (PCP), polychlorinated biphenyls (PCBs), and munitions constituents have phytodegradation potential (USEPA 2006).

3. Phytovolatilization

Phytovolatilization is the uptake of a contaminant into a plant and its subsequent transpiration to the atmosphere, or the transformation or phytodegradation of the contaminant with subsequent transpiration of the transformation or degradation products to the atmosphere. Phytovolatilization generally is applied to groundwater but also can be applied to soluble soil contaminants (USEPA 2006).

Transformation or degradation of the contaminant within the plant can create a less toxic product that is transpired; however, degradation of some contaminants, like trichloroethene (TCE), may produce even more toxic products (e.g., vinyl chloride). Once in the atmosphere, these products may be degraded more effectively by sunlight (photodegradation) than they would be by the plant (phytodegradation), but the potential advantages and disadvantages of phytovolatilization must be assessed on a site-specific basis (USEPA 2006).

Phytovolatilization has been applied to both organic and inorganic (e.g., selenium, mercury, arsenic) contaminants, but it must be reiterated that simply volatilizing a contaminant may not be an acceptable alternative (USEPA 2006).

4.Rhizodegradation

The rhizosphere is the zone of soil influenced by plant roots. Essentially, rhizodegradation is "plant-assisted bioremediation" in that the root zone enhances microbial activity, thus increasing the breakdown of organic contaminants (such as petroleum hydrocarbons, PAHs, pesticides, BTEX, chlorinated solvents, PCP, PCBs, and surfactants) in the soil. The rhizosphere extends only about 1 mm from each root. The presence of plant roots moderates soil moisture and increases soil aeration, making conditions more favorable to bioremediation. The production of root exudates, such as sugars, amino acids, and other compounds, stimulates the population growth and activity of native microbes. Root exudates also may serve as food for the microbes, which can result in cometabolism of contaminants as degradation of exudates occurs. Because the microbes consume nutrients, the plants in a rhizodegradation plot often require additional fertilization (USEPA 2006).

Rhizodegradation actually breaks down contaminants; thus, plant harvesting and disposal is not necessary. In some instances, complete mineralization of the contaminant can occur. The success of this technique is site-specific, however, and laboratory microcosms may not reflect the microbial conditions encountered in the field. Petroleum hydrocarbons have been degraded successfully in the rhizosphere, but degradation of aged hydrocarbons has been shown to be more problematic (USEPA 2006).

5.Phytosequestration

Phytosequestration, also referred to as phytostabilization, is a mechanism that immobilizes contaminants, mainly metals, within the root zone, limiting their migration. Immobilization of contaminants can result from adsorption of metals to plant roots, formation of metal complexes, precipitation of metal ions (e.g., due to a change in pH), or a change to a less toxic redox state. Phytosequestration can occur when plants alter the chemical and microbial makeup of the soil (e.g., through the production of exudates or carbon dioxide), which impacts the fate and transport of the soil metals. (USEPA 2006) Although transport proteins within the plant facilitate the transfer of contaminants between cells, plant cells contain a compartment called the vacuole that acts, in part, as a storage and waste receptacle for the plant. The vacuoles of root cells can sequester contaminants, preventing further translocation to the xylem (ITRC 2009).

Because contaminants are retained in the soil, phytosequestration does not require plant harvesting and disposal; however, evaluation of the system is necessary to verify that translocation of contaminants into the plant tissue is not occurring. Due to the continuing presence of contaminants in the root zone, plant health must be monitored and maintained to ensure system integrity and prevent future release of contaminants. Phytosequestration also can be used to prevent migration of soil contaminants with wind and water erosion, soil dispersion, and leaching (USEPA 2006).

6. Phytohydraulics

Phytohydraulics is the ability of vegetation to evapotranspire sources of surface water and groundwater. Water interception capacity by the aboveground canopy and subsequent evapotranspiration through the root system can limit vertical migration of water from the surface downward. The horizontal migration of groundwater can be controlled or contained using deep-rooted species, such as prairie plants and trees, to intercept, take up, and transpire the water. Trees classified as phreatophytes are deep-rooted, high-transpiring, water-loving organisms that send their roots into regions of high moisture and can survive in conditions of temporary saturation. Typical phreatophytes include species such as cottonwoods, poplars, and willows (ITRC 2009).

Source: USEPA. 2006. In Situ Treatment Technologies for Contaminated Soil: Engineering Forum Issue Paper. EPA 542-F-06-013.

ITRC (Interstate Technology & Regulatory Council). 2009. Phytotechnology

Technical and Regulatory Guidance and Decision Trees, Revised. Phyto-3

PIC = Prior Informed Consent
The Rotterdam Convention on Prior Informed Consent (PIC) is a global treaty that came into force in February 2004, with the intention to protect developing countries from the import of dangerous chemicals. The PIC Convention is implemented in the EU by means of regulation concerning the export and import of dangerous chemicals. Under the proposed recast of this PIC Regulation, the companies will continue to notify to their national authorities their intention to export banned or severely restricted chemicals. ECHA will take over the task to communicate with the destination country and to keep a register of the notifications.

Source: News from ECHA, No 5, Oct 2011, http://echa.europa.eu/doc/press/newsletter/echa_newsletter_2011_5.pdf

Plant breeding is the science and practice of changing the genetics of plants for the benefit of mankind. Plant breeding can be accomplished through many different techniques ranging from simply selecting plants with desirable characteristics for propagation, through induced mutagenesis and following selection to more complex molecular techniques.

For several thousand years, farmers have been altering the genetic makeup of the crops they grow. Human selection for features such as faster growth, larger seeds or sweeter fruits has dramatically changed domesticated plant species compared to their wild relatives. Remarkably, many of our modern crops were developed by people who lacked an understanding of the scientific basis of plant breeding.

Despite the poor understanding of the process, plant breeding was a popular activity. Gregor Mendel himself, the father of genetics, was a plant breeder, as were some of the leading botanists of his time. Mendel's 1865 paper explaining how dominant and recessive alleles could produce the traits we see and could be passed to offspring was the first major insight into the science behind the art. The paper was largely ignored until 1900, when three scientists working on breeding problems rediscovered it and publicized Mendel's findings.

Major advances in plant breeding followed the revelation of Mendel's discovery. Breeders brought their new understanding of genetics to the traditional techniques of self-pollinating and cross-pollinating plants.

modern landfills are designed to protect both public health and the environment by providing physical containment of trash, isolation from air and water, and control of landfill gas, leachate, odors, disease vectors, and other nuisances. Modern landfill technology provides hydrologic isolation with various systems of liners and surface capping using compacted clay, plastic membranes, or both; as well as an overlay of about 18 inches of earthen material and at least six inches of soil to support native plant growth and control erosion. Final cover systems are also expected to meet aesthetic and other post-closure site end use criteria for waste management sites. These systems are intended to achieve their functional requirements for time periods of many decades to hundreds of years.

Questions about the long-term performance of the low-permeable layers in conventional cover designs have prompted significant interest and research into alternative designs. Alternative landfill cover systems emerged in the late 1990s as a possible cost-effective option to conventional covers and have been applied at some landfills and other types of waste management units (e.g., waste piles and surface impoundments). The implementation of an alternative cover system is dependent on specific site characteristics. The site characteristics that have a dominant influence on the choice of an appropriate final cover include climate, soils, landfill waste characteristics, hydrogeology, gas production, seismic environment, and reuse of landfill areas.

There are various alternatives to conventional covers. This site focuses on covers that utilize natural processes to manage water precipitating on waste containment sites, commonly known as evapotranspiration (ET) covers. These covers have proven an effective means of containing waste at municipal landfills, hazardous, and industrial waste landfills. There are other types of alternatives to conventional cover systems, such as asphalt barriers. However, these are not addressed on this site because they are not evapotranspiration covers.

ET covers are also known as store and release covers, vegetative covers, sponge and pump covers, alternative final covers (AFC), alternative final earthen covers (AFEC), and other names. They include various combinations of earthen materials and plants, and generally can be categorized into the following cover types:

Monolithic: Any precipitation water is stored in a layer of soil and later removed through evapotranspiration.

Capillary break: This cover uses a two layer system to increase the water storage capacity of the cover. A capillary break is formed by two layers – a layer of fine soil over a layer of coarser material (e.g. sand or gravel). Capillary force causes the layer of fine soil overlying the coarser material to hold more water than if there were no change in particle size between the layers.

Dry barrier: The dry barrier cover uses wind-driven airflow through the layer of coarse material to remove water from a storage layer.

Source: US-EPA, Clu-In: http://www.clu-in.org/products/evap/

there are 16 elements that are essential nutrients for plant growth. Plants can only take those nutrients from soils if they are easily available or in specific chemical forms. Chemical, physical and biological processes contribute to the availability of these nutrients in soils. In this context, processes carried out by soil biota are important for the maintenance of crop production and good crop yields. They also contribute to plant nutrition in areas where chemical fertilizers cannot be applied. Below are some examples of how the soil biota can contribute to the formation of nutrient pools and the availability of nutrients.

Source: EUROPEAN ATLAS OF SOIL BIODIVERSITY, JRC, European Comission, 2010

EU legislation regulates the marketing and use of plant protection products and their residues in food.

Council Directive 91/414/EEC concerning the placing of plant protection products on the market lays down rules and procedures for approval of the active substances at EU-level and for the authorisation at Member State level of plant protection products (PPPs) containing these substances. This Directive states that substances cannot be used in plant protection products unless they are included in a positive EU list. Once a substance is included in the positive list Member States may authorise the use of products containing them.

Pesticides residues in food are regulated by Regulation (EC) No 396/2005 . The legislation covers the setting, monitoring and control of pesticides residues in products of plant and animal origin that may arise from their use in plant protection. The maximum levels set are those consistent with good agricultural practice in Member States and third countries. The levels are set after an evaluation of any risks to consumers of different age groups and they are only set if they are considered safe. Nonetheless, MRLs (Minimal Risk Level) exceedences are closely monitored, evaluated and communicated to the authorities in the Member States through the Rapid Alert System for Food and Feed whenever there is a potential risk to consumers.

Both Directive 91/414 on the placing on the market of plant protection products and Regulation 396/2005 on pesticide residues in food and feed aim at a high level of protection of human health and the environment.

The European Parliament approved new EU pesticides legislation in January 2009, which will increase the number of pesticides available in Member States, while in due course banning the use of certain dangerous chemicals in these products. Measures to ensure the safer use of pesticides in daily life will also be introduced.

The key points of the new regulation, which deals with the production and licensing of pesticides, are as follows:

• A positive list of approved "active substances" (the chemical ingredients of pesticides) is to be drawn up at EU level. Pesticides will then be licensed at national level on the basis of this list.

• Certain highly toxic chemicals will be banned unless exposure to them would in practice be negligible, namely those which are carcinogenic, mutagenic or toxic to reproduction, those which are endocrine-disrupting, and those which are persistent, bioaccumulative and toxic (PBT) or very persistent and very bioaccumulative (vPvB).

• For developmental neurotoxic and immunotoxic substances, higher safety standards may be imposed.

• If a substance is needed to combat a serious danger to plant health, it may be approved for up to five years even if it does not meet the above safety criteria.

• Products containing certain hazardous substances are to be replaced if safer alternatives are shown to exist. MEPs successfully demanded a shorter deadline for their replacement, of three years rather than five.

• Substances likely to be harmful to honeybees will be outlawed.

see plant protection products directive, 91/414/EEC

plutonic rocks (also called intrusive igneous rocks) resulted from magmas solidified below ground. When magmas crystallize deep underground they look different from volcanic rocks because they cool more slowly and, therefore, have larger crystals. Igneous rocks cooled beneath the Earth's surface are called intrusive rocks. The intrusive equivalents of basalt, andesite, and rhyolite are gabbro, diorite, and granite, respectively. In Hungary the Velencei mountain is composed of intrusive igneous rocks such as, granodiorite and diorite and the granite block in Mórágy was formed in similar conditions.

The underground crystallization stages of the magma are the following:
A. Preliminary crystallization stage (approx. 1100–1000 °C)
During the preliminary crsystallization stage ultrabasic and basic rocks are formed. The temperature decrease results separation of the silicate and sulphide melts. The preliminary crystallization gives economically important ore deposits: chromite, magnetite, ilmenite, platina, diamond and apatite.
B. Main crystallization stage (approx. 1000–700 °C)
In the main crystallization stage the magma solidification occurs. The olivine, pyroxene, amphiboles and the feldspars crystallize in parallel and finally the quartz.
C. Post magmatic stage (from approx. 700 °C)
The volatile containing residual magma is crystallised in this phase. The post magmatic stage includes three phases:

Pegmatite phase (approx. 700–550 °C): The mineral composition of the pegmatites crystallized in this phase is identical with that of the main crystallization phase however the pegmatites contain much larger crystals. The pegmatites in general occur in veins and are rich in rare elements such as stanium, uranium, thorium, boron, lithium, berillium, zirconium, titanium, tanthal.

Pneumatolitic phases (approx. 550–375 °C): The halogene rich solutions are chemically very active and thus are able to considerably modify the solidified rocks. This phase results various minerals such as quartz, fluorite, wolframite, turmaline.

Hydrothermal phase (from approx. 375 °C): The water diluted, solutions of the residual magma penetrated the cracks, voids of the rocks forming hydrothermal veins. During the hydrothermal phase mainly the following metals are concentrated: gold, silver, copper, lead, zinc, mercury and the iron, cobalt and nickel remained still in the residual solution.

the illegal killing of animals or fish, a great concern with respect to endangered or threatened species.

point and non-point sources of water pollution means the sources of pollutants and nutrients the input of which to waters is caused either by locally determined discharges (point source) or by diffuse effects being widespread over the catchment areas (non-point or diffuse sources).

polychlorinated dibenzofurans (PCDFs) are a group of halogenated organic componunds with a furane skeleton and chlor substituents different in numer. PCDFs occur as by-products in the manufacture of chlorinated organic substances, in the incineration of chlorine-containing substances such as PVC, in the bleaching of paper, and also from natural sources such as volcanoes and forest fires. Somilar to polychlorinated dibenzodioxins (PCDDs), they have been shown to bioaccumulate in humans and and animals, are known toxic, mutagenic, carcinogenic and reprotoxic.

the place where a hazardous substance comes from, such as a landfill, waste pond, incinerator, storage tank, or drum. A source of contamination is the first part of an exposure pathway. The source may ba a point or a diffuse source.