Lexikon
an antibiotic (from the Ancient Greek: anti = "against", and bios = "life") is a substance or compound that kills or inhibits the growth of bacteria or other microorganisms. It is based on a natural phenomenon, antibiosis, which means antagonistic association between an organism and the metabolic substances produced by another. Formerly only the microbes-made substances were called "antibiotics", but today all man-made, synthetic or semisynthetic compounds are called "antibiotic", which are prodused and used for the inhibition or killing microbes. We distinguish between antibacterial, antifungal, antiprozoal etc. Antibiotics, depending on the target of the antibiotic agent. Antibiotics belong to the broader group of antimicrobial compounds, used to treat infections in humans and animals caused by microorganisms, to treat food or fodder to prevent fauling and infections through nutrition, etc.
microorganisms easily get resistant to antibiotics, due to a special mechanism, where the gene responsible for the antibiotic resistence moves from one organism to the other in form of mobile genetic elements, causing rapid transformation of a sensitive bacterial populations (e.g. in human body) into a resistent one.
See also antibiotic resistance
a bit is a specific amount of information found in computers. It is abreviation of Binary Unit.
Bytes, kilobytes, megabytes and gigabytes are all increasing levels of bits. A bit is the smallest piece of computer memory. It is either 1 or 0, meaning on or off. It is exactly one-eighth.
a collective term for chlorinated derivatives of benzene, toluene, phenol, naphthalene and bi-phenyl and other compounds containing at least one benzene ring. Chlorinated aromatics are widely used as intermediates in the manufacture of medicines, agricultural chemicals and paints.
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
the aim of dietetics is topromote good health through proper eating. The dietitian supervise the preparation and service of food, develop modified diets, participate in research, and educate individuals and groups on good nutritional habits. In a medical setting, a dietitian may provide specific artificial nutritional needs to patients unable to consume food normally.
epigenetics refers to mechanisms that persistently alter gene expression without actual changes to the gene/DNA sequence. DNA methylation is an example of an epigenetic mechanism. Scientists have shown that DNA methylation is an important component in a variety of chemical-induced toxicities, including carcinogenicity, and is a mechanism that should be assessed in the overall hazard assessment
Source: Watson, R.E. & Goodman, J.I. (2002). Epigenetics and DNA methylation come of age in toxicology. Toxicol. Sci. 67, 11−16.
ergonomics is the science of designing the job, equipment, and workplace to fit the worker. Proper ergonomic design is necessary to prevent repetitive strain injuries, which can develop over time and can lead to long-term disability.
The International ergonomics Association defines ergonomics as follows: "ergonomics (or human factors) is the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance."
ergonomics is employed to fulfill the two goals of health and productivity. It is relevant in the design of such things as safe furniture and easy-to-use interfaces to machines.
the first of the -omics technologies to be developed, genomics has resulted in massive amounts of DNA sequence data requiring great amounts of computer capacity. Genomics has progressed beyond sequencing of organisms (structural genomics) to identifying the function of the encoded genes (functional genomics).
International Classification for Standards (ICS) is an international classification system for technical standards. It is designed to cover every economic sector and virtually every activity of the humankind where technical standards may be used.
Developed and maintained by the International Organization for Standardization, the ICS is intended to be a continuous work in progress and is updated when necessary. The latest edition of the ICS can be downloaded free of charge from the ISO web site.
Anyone may submit a proposal for modifications or additions to the ICS.
(Source: Wikipedia)
nitroaromatics are carcinogenic and mutagenic aromatic substances, that are typical contaminants of contaminated military sites, e.g. 2,4,6-Trinitrotoluene (TNT), 2,4-Dinitrotoluene (DNT), 1,3,5-trinitro-1,3,5-triazine (also known as RDX), cyclotetramethylene tetranitramine (also known as HMX), some pesticides (atrazine), and a number of anilines. (Source: EUGRIS)
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:
- assist in the interpretation of other toxicological data,
- select doses for other toxicological studies, and/or
- extrapolate data from animals to the human (OECD).
Source: http://alttox.org/ttrc/toxicity-tests/pharmacokinetics-metabolism/
proteomics is the study of protein molecules in the cell to find association with the composition and cellular response to toxic chemical substances. It is an innovative tool in pharmacology, toxicology and environmental toxicology.
Proteins are the primary structural and functional molecules in the cell, and are made up of a linear arrangement of amino acids. The linear polypeptide chains are folded into secondary and tertiary structures to form the functional protein. Unlike the static nature of the cell's genes, proteins are constantly changing to meet the needs of the cell.
Characterizing the identity, function, regulation, and interaction of all of the cellular proteins of an organism, the proteome, will be a major achievement. Studies of changes in the proteome of cells and tissues exposed to toxic materials, compared to normal cells, is being used to develop an understanding of the mechanisms of toxicity. As proteomics tools become more powerful and widely used, protein and proteome changes in response to exposures to toxic substances (fingerprints or response profiles) will be developed into databases that can be used to classify exposure responses at various levels of organization of the organism, thus providing a predictive in silico toxicology tool.
solar photovoltaics (PVs) are arrays of cells containing a material, such as silicon, that converts solar radiation into electricity. Today solar PVs are used in a wide range of applications, from residential rooftop power generation to medium-scale utility-level power generation.
The Concentrated Solar Power (CSP) systems use mirrors or reflective lenses to focus sunlight on a fluid to heat it to a high temperature. The heated fluid flows from the collector to a heat engine where a portion of the heat is converted to electricity. Some types of CSP allow the heat to be stored for many hours so that electricity can be produced at night.
a branch of mathematics that deals with collecting, reviewing, summarizing, and interpreting data or information. Statistics are used to determine whether differences between study groups are meaningful.
the expression of toxicity arising from exposure to a substance is a consequence of a chain of events that results in the affected tissues of an organism receiving the ultimate toxicant in amounts that cause an adverse effect. The concentration of the ultimate toxicant at the biological target site depends on the absorption, distribution, metabolism and excretion. According to REACH annexe VIII, the assessment of these processes, i.e. the toxicokinetics behaviour is required from the relevant available information. There is no obligation to generate new data.
Source: REACH