Lexikon

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acute lymphoblastic leukemia (ALL)

a rapidly progressing cancer in which a large number of abnormal white blood cells - called lymphoblasts - are present in the blood and in the bone marrow. Also called acute lymphocytic leukemia (ALL). It is frequent in childhood. Main causes mey be mutaganic agents or chemical substances.

aliphatic hydrocarbons
hydrocarbons in which the carbon-hydrogen groupings are arranged in open chains (that might include branches). The term includes paraffins and olefins and provides a distinction from aromatics and naphthenes, which have at least some of their carbon atoms arranged in closed chains or rings. The paraffins, called also alkanes are saturated hydrocarbons, in their molecules the carbon atoms are bound by single bonds, e.g. hexadecane (C16H34). The olefins are unsaturated hydrocarbons, in their molecules there are carbon atoms, which are bound by double bond, e.g. hexadecene (C16H34) contains one double bond, butadiene (C4H4) contains two double bonds.
aliphyatic compound

aliphatic compounds are acyclic or cyclic, non-aromatic carbon compounds.

In aliphatic compounds, carbon atoms can be joined together in straight chains, branched chains, or non-aromatic rings (in which case they are called alicyclic). Aliphatic compounds can be saturated, joined by single bonds (alkanes), or unsaturated, with double bonds (alkenes) or triple bonds (alkynes). Besides hydrogen, other elements can be bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine.

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

alpha-ketoglutaric acid

alpha-ketoglutaric acid bounds ammonia (in the form of α-ketoglutarate) produced by de-amination of glutamate. It plays important role in the Krebs-cycle, in the synthesis of amino-acid glutamine, in the ammonia-cycle. It is co-substrate for some oxigenase enzymes.

It is used as dietary supplement, mainly for body builders.

aluminium phosphide

aluminium phosphide is an inorganic compound used as a wide band gap semiconductor and a fumigant. This colourless solid is generally sold as a grey-green-yellow powder due to the presence of impurities arising from hydrolysis and oxidation. It has a strong, garlic like smell.

EC Number: 244-088-0; CAS number: 20859-73-8

It is not a highly flammable solid, but in contact with water it evolves highly flammable gases in dangerous quantities. The gas ignites spontaneously. Phosphine (PH3) is produced when hydrolysing.

Aluminium phosphid is used as a rodenticide, insecticide, and fumigant for stored cereal grains. It is used to kill small verminous mammals such as moles, and rodents. The tablets or pellets typically also contain other chemicals that evolve ammonia which helps to reduce the potential for spontaneous ignition or explosion of the phosphine gas.

As a rodenticide, aluminium phosphide pellets are provided as a mixture with food for consumption by the rodents. The acid in the digestive system of the rodent reacts with the phosphide to generate the toxic phosphine gas. Other pesticides similar to aluminium phosphide are zinc phosphide and calcium phosphide.

Aluminiumphosphid a semiconductor material is usually alloyed with other binary materials for applications in devices such as light-emitting diodes, such as aluminium gallium indium phosphide.

It is classified under REACH and CLP as following:

Hazard classes, Hazard categories

  • Water-reactivity 1
  • Acute Toxicity 2
  • Acute Toicity 3
  • Aquatic Acute 1

Hazard statements

  • H260 In contact with water releases flammable gases which may ignite spontaneously
  • H300 Fatal if swallowed
  • H311 Toxic in contact with skin
  • H400 Very toxic to aquatic life

Sources:

http://echa.europa.eu/doc/consultations/cl/CLH_AXVREP_DE_Aluminium+phosphide.pdf

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

asphaltene
constituents of petroleum products with a high molecular mass (3 000-10 000) not dissolving in pentene, but dissolving in carbon disulfide. Chemically they are PAHs linked by aliphatic chains or rings and functional groups.
atmosphere

atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night. Dry air contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1%.

The atmosphere has a mass of about 5 × 1018 kg, three quarters of which is within about 11 km (6.8 mi; 36,000 ft) of the surface. The atmosphere becomes thinner and thinner with increasing altitude, with no definite boundary between the atmosphere and outer space. An altitude of 120 km (75 mi) is where atmospheric effects become noticeable during atmospheric reentry of spacecraft. The Kármán line, at 100 km (62 mi), also is often regarded as the boundary between atmosphere and outer space.

Source: Wikipedia

atmosphere of the Earth

atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night. Dry air contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1%.

The atmosphere has a mass of about 5 × 1018 kg, three quarters of which is within about 11 km (6.8 mi; 36,000 ft) of the surface. The atmosphere becomes thinner and thinner with increasing altitude, with no definite boundary between the atmosphere and outer space. An altitude of 120 km (75 mi) is where atmospheric effects become noticeable during atmospheric reentry of spacecraft. The Kármán line, at 100 km (62 mi), also is often regarded as the boundary between atmosphere and outer space.

Source: Wikipedia

biological soil tretament in slurry phase reactor
biphenyl

biphenyl is an aromatic hydrocarbon with a molecular formula (C6H5)2.

CAS number 92-52-4

PubChem 7095

ChemSpider 6828 Yes

Molecular formula: C12H10

Molar mass: 154.21 g mol−1

Appearance: colorless crystals

Density: 1.04 g/cm3[1]

Melting point: 69.2 °C, 342 K, 157 °F

Boiling point: 255 °C, 528 K, 491 °F

Solubility in water: 4.45 mg/L

Flash point: 113 °C (235 °F)

Autoignition

temperature: 540 °C (1,004 °F)[

Hazards

EU Index 601-042-00-8

EU classification: Irritant (Xi), Dangerous for the environment (N)

R-phrases R36/37/38 R50/53

S-phrases (S2) S23 S60 S61

It is notable as a starting material for the production of polychlorinated biphenyls (PCBs), which were once widely used as dielectric fluids and heat transfer agents. Biphenyl is also an intermediate for the production of a host of other organic compounds such as emulsifiers, optical brighteners, crop protection products, and plastics.

chemical soil treatment in slurry phase reactor
chlorinated aliphatics
chlorophenols

chlorophenols are derivatives of phenols that contain one or morecovalenly bonded chlorine atoms. Most chlorophenols have a number of different isomer. Monochlorophenols have three isomers because there is only chlorine atom which can occupy one of three ring positions on the phenol molecule; dichlorophenols have 4, trichlorophenols: 6, tetrachlorophenols: 3, and pentachlorophenols only one.
In the past, it has been used as a herbicide, insecticide, fungicide, algaecide, disinfectant and as an ingredient in antifouling paint. Some applications were in agricultural seeds (for nonfood uses), leather, masonry, wood preservation, cooling tower water, rope and paper mill system.
Since the early 1980s, the purchase and use of PCP in the U.S has not been available to the general public. Nowadays most of the PCP is restricted to the treatment of utility poles and railroad ties.

chromatographic fingerprint

representation of the composition of a substance from the characteristic distribution of constituents in an analytical chromatogram.

chromatography

chromatography is a separation method based on the difference in interactions between the components of the sample dissolved in a fluid phase (gas or liquid) and the stationary phase. The driving force of the transport between the phases is the difference in chemical potential. The retention in the stationary phase (partition) depends on the interactions of the molecules, ions, atoms of the sample. As a consequence, their average velocity will be different, and they leave the stationary phase separated. The separated components are detected based on their physical or chemical properties. The stationary phase can be solid or liquid. The mobil phase can be gas, supercritical fluid or liquid. Depending on the mobil phase the chromatographic techniques are classified as gas chromatography, supercritical fluid chromatography and liquid chromatography. (Source: Balla J.: Analytical applications of gas chromatography. Budapest, 1987) All of these chromatographic techniques are widely used for characterization of various mixtures, e.g. environmental samples in site assessment, technology monitoring, etc.

contaminant-phase

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

Daphnia
Daphnia acute toxicity test
Daphnia chronic toxicity test
elimination of sulphur dioxide
environmetal phases
EPH
extractable (Total) petroleum hydrocarbon , that is the DRO range (Diesel Range Organics, which consists of hydrocarbons containing between 10 and 30 carbon atoms and includes a mixture of alkanes, cycloalkanes, branched alkanes, alkenes and heterocyclic compounds. The Extended DRO range includes compounds with up to 40 carbon atoms and includes compounds found in lubricating oils. DRO is distinguished from GRO (Gasoline Range Organics) that is from VPH, VTPH containing the volatile extractable petroleum hydrocarbons having less than 12 carbon atoms in their molecules.
epinephrine
ETPH
extractable Total petroleum hydrocarbons, in other name extractable petroleum hydrocarbons (EPH) or diesel oil Range Organics (DRO). The contaminated soil is extracted by organic solvent usually e.g. by hexane and after purification the extract is measured by gas chromatography.
flame atom emission photometry
gas chromatography

gas chromatography is an analytical technique employing a gaseous mobile phase that separates mixtures into their individual components. The stationary phase can be solid or immobilized liquid. The separation is based on dynamic sorption-desorption processes. Compounds volatilized without decomposition can be separated. The technique is not suitable for the separation of ionic compounds and of large molecules like proteins, peptides, polysacharides, etc. (Source: Balla J.: Analytical applications of gas chromatography. Budapest, 1987)

In environmental analysis gas chromatography is applied for the measurement of volatile and semivolatile organic compounds (VOC and SVOC, resp.) in air, in surface and subsurface water, as well as in potable water, in soil, of residual content of a chemical in food, in animal and plant samples. It is applied for identification of the source of the contamination, the transport of contaminants, bioaccumulation, assessment of contaminated sites, technology monitoring, etc.

Geographical Information Systems (GIS)
a computer system to assemble, store, manipulate, and display geographically-referenced information, i.e. data identified according to their locations. Geographic information systems (GIS) technology can be used for scientific investigations, resource management and development planning. (Source: EUGRIS)
GIS, Geographical Information System

a geographic information system (GIS), captures, stores, analyzes, manages, and presents data that refers to or is linked to location. An information system that integrates, stores, edits, analyzes, shares, and displays geographic information. In a more generic sense, GIS applications are tools that allow users to create interactive queries (user created searches), analyze spatial information, edit data, maps, and present the results of all these operations.

graphite furnace atomic absorption spectroscopy
a technique for elementary analysis using electrothermal atomization, abbreviated as GAAS. Samples in solution or in solid form are deposited on the surface of a graphite tube, which is then heated to high temperature to vaporize and thermally dissociate the sample. Graphite can be heated reproducibly; it will be sublimated at 3700 oC. The experimental error in measurement of solid samples can be decreased by measuring suspensions. The method is used for environmental samples (soil, ground water), solid and liquid wastes.
High Density Nonaqueous Phase Liquid HDNAPL
High Density Nonaqueous Phase Liquid. See as DNAPL.
hypophysis

the pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and weighing 0.5 g. It is considered a master gland. The pituitary gland secretes hormones regulating homeostasis, including tropic hormones that stimulate other endocrine glands. It is functionally connected to the hypothalamus by the median eminence.

ion cromatography
lipophyllic
liquid chromatography
a chromatographic technique which employs a liquid mobile phase. The separation is based on the partition of components between the mobile and the stationary phase. The High Performance liquid chromatography (HPLC) is widely used in the environmental analysis.
lithosphere

in the Earth, the lithosphere includes the crust and the uppermost mantle, which constitute the hard and rigid outer layer of the Earth. The lithosphere is underlain by the asthenosphere, the weaker, hotter, and deeper part of the upper mantle. The boundary between the lithosphere and the underlying asthenosphere is defined by a difference in response to stress: the lithosphere remains rigid for very long periods of geologic time in which it deforms elastically and through brittle failure, while the asthenosphere deforms viscously and accommodates strain through plastic deformation. There are two types of lithosphere: 1) oceanic lithosphere, which is associated with oceanic crust and exists in the ocean basins, 2) continental lithosphere, which is associated with continental crust. The composition of the two types of crust differs markedly, with basaltic rocks ("mafic") dominating oceanic crust, while continental crust consists principally of lower density granitic rocks ("felsic"). The lithosphere is broken into tectonic plates. The following tectonic plates currently exist on the earth's surface with roughly definable boundaries. There are seven primary plates (African Plate, Antarctic Plate, Eurasian Plate, Indo-Australian Plate, North American Plate, Pacific Plate, South American Plate) and some secondary smaller plates (Arabian-, Caribbean-, Cocos-, Scotia-, Adria-, Aegean-, Arab-, Iranian-, Nazca-, Philippine Sea -plates).These plates are rigid segments that move in relation to one another at one of three types of plate boundaries: 1) convergent boundaries, at which two plates come together, (an example of such a boundary is the San Andreas fault in California) 2) divergent boundaries, at which two plates are pulled apart (the Atlantic Ocean was created by this process, the mid-Atlantic Ridge is an area where new sea floor is being created), and 3) transform boundaries, in which two plates slide past one another laterally. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation can occur along these plate boundaries. The tectonic plates ride on top of the asthenosphere, the solid but less-viscous part of the upper mantle that can flow and move along with the plates, and their motion is strongly coupled with patterns convection inside the Earth's mantle. An example of this is the Nazca plate being subducted under the South American plate to form the Andes Mountain Chain.

Low Density NonAqueous Phase Liquid LDANPL
Low Density, Non Aquaeous Phase Liquid LDNAPL or NAPL
metamorphic rocks

The metamorphic rock is the result of the transformation of an existing rock type in a process called metamorphism, which means "change in form". The metamorphic rock is any rock derived from pre-existing rocks by mineralogical, chemical, and/or structural changes, essentially in the solid state, in response to marked changes in temperature, pressure, shearing stress, and chemical environment .The metamorphic rocks can be derived from sedimentary, igneous or another older metamorphic rock after having been subjected to heat and pressure (temperatures greater than 150 to 200 °C and pressures of 1500 bars) causing profound physical and/or chemical change. Metamorphic rocks make up a large part of the Earth's crust and are classified and named by texture, by chemical and mineral assemblage and by the characteristics of the preexisting rock. The mineral compositition of the metamorphic rocks depends on the composition of the preexisting rock, according to which the metamorphic rocks are grouped as: ultramafic, mafic, pellitic (clayee), carbonate bearing, quartz and quartz-feldspar containing rocks. Most metamorphic rocks are named based on their texture and structural features, and their mineralogy. The first step in naming a metamorphic rock is to always identify whether the rock is foliated or non-foliated. Among the foliated textures, metamorphic rocks are further classified based on how the minerals within the parent rock are affected by the changes in temperature and pressure. In general terms, increases in temperature and pressure result in different, more complex textures, and different foliated metamorphic rocks: foliated (slate, phyllite, schist, gneiss) and non-foliated. Non-foliated metamorphic rocks are usually named exclusively on the basis of mineral composition (hornfels, amphibolite, quartite). A close examination of the non-foliated rock will reveal the dominant one or two minerals within the rock. In some cases one may choose some prefix-type modifiers to attach to names to stress some important or unusual textural or mineralogical aspects. For example an “ortho”- prefix indicates an igneous parent, and a “para”- prefix indicates a sedimentary parent (orthogneiss, paragneiss). Metamorphic rocks are characterised by typical mineral assemblages according to the preexisting rock and the intensity of metamorphism. The intensity of metamorphism and the relevant metamorphic rocks are shown below:

  • Very low intensity metamorphism (shale, metabasalt). Typical minerals: clay minerals, laumontite (zeolit), prehnite (zeolit).
  • Low intensity metamorphism (serpentinite, chlorite shale, sericite shale). Typical minerals: sericit, pyrophyllite, chlorite.
  • Medium intensity metamorphism (mica schist, marble). Typical minerals: mica, quartz, plagioclase, garnite, andalusite.
  • High intensity metamorphism (eclogite, gneiss). Typical minerals: quartz, muscovite, biotite, plagioclase, kaliumfeldspar, sillimanite, staurolite.
metamorphism

in the geological terminology metamorphism means solid state changes in sedimentary, igneous and even metamorphic rocks. It takes place within the crust and in response to the agents of metamorphism: heat, pressure, chemically active fluids. The types of metamorphism are: 1. dynamic metamorphism that occurs along faults zones in response to pressure; 2. contact metamorphism resulting alteration of rocks at or near the contact of a cooling pluton; regional metamorphism occuring over a very large area in response to increased temperature and pressure.

mobile phase
in chromatography, the phase (gaseous or liquid) responsible for moving an introduced sample through a porous medium (stationary phase) to separate components of interest.
multi-phase extraction of contaminated soil

multi-phase extraction uses a vacuum system to remove various combinations of contaminated groundwater, separate-phase petroleum product, and vapors from the subsurface. The system lowers the water table around the well, exposing more of the formation. Contaminants in the newly exposed vadose zone are then accessible to vapor extraction. Once above ground, the extracted vapors or liquid-phase organics and ground water are separated and treated.

Source: US-EPA, Clu-In:http://www.clu-in.org/techfocus/default.focus/sec/Multi-Phase_Extraction/cat/Overview/

naphtalene
naphthenes
petroleum industry term for a cycloparaffin (cycloalkane).
p-tert-butylphenol

p-tert-butylphenol is used as an intermediate for phenol resins and polycarbonate resins. It is also used as a raw material for construction elements and floors in buildings.

CAS NO: 98-54-4

Melting Point: 99.3 °C
Boiling Point: 237 °C (at 1,013 hPa)
Density: 0.92 g/m3 at 110 °C
Vapour Pressure: 1.3 x 102 Pa at 60 °C
Partition Coefficient (Log Pow): 3.29 at 25 °C
Water Solubility: 610 mg/l at 25 °C
pKa: 10.16 at 25 °Chttp://enfo.hu/mokka/secure/.tmp/glossary/glossary_edit.php

It is not photodegradable, not ready to hydrolyse, readily biodegradable, bioaccumulated by aquatic ecosystem: 34–120.

The production volume of p-t-butylphenol in Japan is 5,000 tonnes/year in 1993. According to ECDIN database, the production volume of USA is 11,000 tonnes/year in 1993. According to IUCLID database, maximum production volume is 10,000 tonnes/year. Less than 5000 tonnes/year are produced in France. Less than 1000 tonnes/year are sold to be used either as a chemical intermediate for the production of vulcanization agents or as for the production of phenolic resins.

The potential environmental distribution of p-t-butylphenol obtained from a generic fugacity model (Mackey level III) shows that it will be mainly distributed to water. The main route of human exposure is inhalation with a limited numbers of workers potentially exposed during sampling and bag or tank filling operations.

No concentration was measured and no presence of the substance was detected in the environment. Release into environment may happen only from production or transport, because the substance is not used out of the production site. Distribution in the environment when released into air, water and soil can be calculated by transport modelling:
released into air: air: 39.7%; water: 23.3%; soil: 35.9%; sediment: 1.1%;
released into water: air: 0.2%; water: 95.3%; soil: 0.2%; sediment: 4.4%;
release into soil: air: 0.0%; 99.6 %; soi: 0.4%; sediment: 0.0%.

Acute toxicity of p-t-butylphenol is low via any administration routes. This chemical is considered as an irritant to the skin, eyes and respiratory tract. The possibility of skin sensitization in humans still remains because of some positive results in human patch tests, despite negative results in animal experiments (OECD TG 406). The depigmentation was observed on the skin of various animals and humans exposed to this chemical. This change was likely induced by exposure to this chemical not only via direct contact but also via inhalation or ingestion route. In the OECD combined repeat dose and reproductive/developmental screening toxicity test (OECD TG 422) of rats by gavage at doses of 20, 60 and 200 mg/kg/day for 46 days, this chemical showed neither systemic toxicity nor reproductive toxicity even at the highest dose of 200 mg/kg/day. Although a noisy respiratory sound was induced in a few females at 200 mg/kg/day, it was considered due to irritation of the respiratory tract caused by this chemical. In a dose-finding study (14 days), this changed to respiratory difficulty, especially at 1,000 mg/kg/day. In other studies by the longer and higher exposure in diet (approx. 1 g/kg b.w./day, for 20 or 51 weeks), forestomach hyperplasia was induced. This chemical showed clear negative results in gene mutation tests. However, one
chromosomal aberration study indicated structural chromosome aberration and polyploidy with metabolic activation in CHL/IU cells (OECD TG 473) although other studies in rat lymphocytes (OECD TG 473) and in rat liver epithelial-type cells resulted in negative. Therefore, the possibility of in vivo genotoxicity still remains. There was no sufficient carcinogenicity study and no evidence of carcinogenesis in manufacturing workers, however, a two-stage carcinogenicity study indicated this chemical has promoting activity of forestomach carcinogenesis (papilloma and squamous carcinoma) in rats treated with N-methyl-N’-nitro-N-nitrosoguanidine (MNNG). Furthermore, since the structural related chemical, BHA, (2(3)-tert-butyl-methoxylphenol) is a clear carcinogen, a carcinogenic potential of this chemical could not be ruled out. It is a reprotoxic substance.

p-t-Butylphenol is a stable solid and is classified as a readily biodegradable chemical (OECD TG 301). Bioaccumulation factors range from 34-120. The lowest acute and chronic toxicity data were 48h EC50 (3.4 mg/l) of Daphnia magna and 21d NOEC (0.73 mg/l) of Daphnia magna, respectively. An assessment factor of 100 was chosen and applied to the chronic toxicity data (NOEC), because only two NOEC values (algae and Daphnia). PNEC of p-t-butylphenol is 7.3 x 10-3 mg/l (OECD classification categories for substances hazardous to the aquatic environment; Class: Acute II), p-tbutylphenol may have potential chronic toxicity to aquatic organisms, because NOEC of Daphnia is relatively low and the chemical has moderately bioaccumulative potential.

Personal protection: safety glasses, good ventilation.

Source: http://www.inchem.org/documents/sids/sids/98544.pdf

periphyton

periphyton is a complex mixture of algae, cyanobacteria, heterotrophic microbes, and detritus that is attached to submerged surfaces in most aquatic ecosystems. It serves as an important food source for invertebrates, tadpoles, and some fish. It can also absorb contaminants; removing them from the watercolumn and limiting their movement through the environment. The periphyton is also an important indicator of water quality; responses of this community to pollutants can be measured at a variety of scales representing physiological to community-level changes.

PET and phtalates

PET, the material of plastic bottles, is chemically polyethylene terephthalate, it contains no phthalates. Phthalates (i.e., phthalate ester plasticizers) are not used in PET, and PET is not a phthalate. Plasticizer phthalates are sometimes used to soften other types of plastic, but they are not used in PET. Some consumers may have incorrectly assumed that PET is a phthalate because PET's chemical name is polyethylene terephthalate. Despite the suffix, PET is not a phthalate. Phthalates are low molecular weight monoesters made from ortho-phthalic acid. By comparison, PET is a high molecular weight polyester made from tere-phthalic acid. Chemically they are very different.

Scientific studies documenting the widespread occurrence of low levels of endocrine disrupting compounds (‘EDC’s) in the environment and the food supply have triggered public concern and media attention. Among those are substances of natural origin or of industrial source which are known to be able to bind to estrogen receptors and thus may –theoretically – act in an organism in the same or a similar way as estrogens do. The scientific discussion about it is already going on for years. Up to now there is no clear evidence as to actual influence on humans.

Water samples from PET-bottles tested in an in vitro test system (YES assay) showed the presence of substances with a hormonal effect which were not identified more specifically. The scientists state that the effect was in particular detected in samples packaged in bottles made of the plastic PET. This has raised questions from the public about the possible effects on health of drinking mineral water from PET bottles.

The study from Goethe University Frankfurt highlights migration from packaging (namely PET) as a significant contributor to the measured estrogenic activity of the tested natural mineral waters. However the results presented are not sufficient to demonstrate such a contribution from the packaging since no compounds were identified, nor measured in the samples, and in addition, similar estrogenic activities were sometimes observed in the same water bottled in either glass or PET packaging. In the absence of detection and quantification of EDC’s or estrogenic substances, the observed estrogenic activity cannot simply be attributed to PET packaging.

The level of estrogenic activity detected in the study, if confirmed, would be in the range of nanograms (billionth of a gram per litre). Such activity resulting from the consumption of the tested waters would represent less than a thousandth of the total estrogens produced endogenously in the body and about one millionth of the allowed EU limit of 60 mg for total migration from packaging.

Sources:

http://www.petcore.org/content/does-pet-contain-phthalates

http://www.napcor.com/pdf/BfR_Assessment.pdf

http://www.napcor.com/pdf/EFBWstatement.pdf

pH
phage

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

pharmacokinetics

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/