Lexikon

aquatic toxicology is based on the response of aquatic ecosystem, both marine and freshwater. Aquatic ecosystem may investigate the whole ecosyste, the diversity of species in a certain ecosystem and compares it to the healthy state of the same ecosystem. According to an other concept toxicology applies toxicity tests on some selected memberes of the aquatic ecosystem and from these results extrapolates on the total ecosystem. The burden of failures is very high in both cases.

the simplest part of mathematics. Arithmetic means addition, subtraction, multiplication, and division (called operations). They are the foundation for all higher mathematics.

elemental arsenic occurs in two solid modifications: yellow, and grey or metallic, with specific gravities of 1.97, and 5.73, respectively. The element is a steel grey, very brittle, crystalline, semimetallic metalloid solid. It tarnishes in air, and when heated rapidly oxidises to arsenous oxide which has a garlic odour.

Arsenic does not often form in its elemental state and is far more common in sulfides and sulfosalts such as arsenopyrite, orpiment, realgar, lollingite and tennantite. Due to the abundance of these arsenic bearing ores and the rarity of native arsenic, it is not an important ore of itself. Native arsenic is found in silver ore veins and is processed along with the silver ore and is therefore is a minor source of arsenic.

Native arsenic is usually found to have a trigonal symmetry but a very rare orthorhombic arsenic is known from Saxony, Germany and is named arsenolamprite. The two minerals are called polymorphs many shapes because they have the same chemistry, As, but different structures.

Arsenic toxicity occurs when a person is exposed to arsenic. Arsenic is a naturally occurring element in the earth crust.

There are two primary forms of arsenic:

• Inorganic arsenic—arsenic combined with oxygen, chlorine, or sulfur; found in the environment
• Organic arsenic—arsenic combined with carbon and hydrogen; found in animals and plants.

Inorganic arsenic is usually more harmful than organic arsenic.

Arsenic occurs naturally in soil and minerals, and may enter the air, water, and soil.

In Hungary there are areas where background concentration of Arsenic is rather high 10 mg/kg in soil and 10 μg/lit in water and as consequence poses risk on human health.

Arsenic toxicity may occur when a person is exposed to toxic amounts of arsenic due to

• Breathing air containing arsenic
• Eating food contaminated with arsenic
• Drinking water contaminated with arsenic
• Living in areas with high natural levels of arsenic
• Working in a job that involves arsenic

a body of surface water created by human activity.

American Standard Code for Information Interchange

ATC code is the Anatomical Therapeutic Chemical Classification System, a system of alphanumeric codes developed by the WHO for the classification of drugs and other medical products.

the REACH Regulation sets up a system under which the use of substances with properties of very high concern and their placing on the market can be made subject to an authorisation requirement. Such substances are included in Annex XIV of the Regulation, and may not be placed on the market or used without an authorisation.This authorisation requirement ensures that risks from the use of such substances are either adequately controlled or outweighed by socio-economic benefits. An analysis of alternative substances or technologies will be a fundamental component of the authorisation process. Source: REACH Glossary

an average or expected concentration of a substance l in a specific environment, or typical concentrations of substances that occur naturally in an environment.

an average or expected imission in the environment of an air polluting source.

bacteria usually control gene expression by regulating the level of mRNA transcription. In bacteria, genes with related function are generally located adjacent to each other and they are regulated co-ordinately . Coordinate regulation of clustered genes is accomplished by regulating the production of a polycistronic mRNA (a large mRNA containing the information for several genes). Thus, bacteria are able to "sense" their environment and express the appropriate set of genes needed for that environment by regulating transcription of those genes.

Bactericides are substances that kill bacteria. Bactericides are either disinfectants, antiseptics or antibiotics. Bactericides are widely used in human and animal therapy, in agriculture plant pesticides and in different industries for killing harmful bacteria.

bacterostatic agent or shotly bacteriostat is a biological or chemical agent that stops bacteria from reproducing, while not necessarily harming them otherwise.

Depending on their application, bacteriostatic antibiotics, disinfectants, antiseptics and preservatives can be distinguished. Upon removal of the bacteriostat, the bacteria usually start to grow again. This is in contrast to bactericides, which kill bacteria.

adopted in 1989 and entered into force on 5 May 1992. The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal aims to minimise the generation of hazardous wastes and control their movement.

Best Available Techniques Not Entailing Excessive Cost.

BEVs store electricity in batteries and draw power from the batteries to run an electric motor that drives the vehicle. So long as the ultimat electricity source is clean, the BEV system can reduce emissions significantly compared with an internal combustion engine vehicle (ICEV) run on a liquid fuel. Indeed, BEVs using WWS power would be completely zero-emission vehicles. Moreover, BEVs get about 5 times more work (in miles of travel) per unit of input energy than do ICEVs (mi/kWh-outlet versus mi/kWh-gasoline). BEVs have existed for decades in small levels of production, and today most major automobile companies are developing BEVs. The latest generation of vehicles uses lithium-ion batteries, which do not use the toxic chemicals associated with lead-acid or the nickel-cadmium batteries (1).

Vehicles using both electric motors and internal combustion engines are examples of hybrid electric vehicles, and are not considered pure (or all) EVs because they operate in a charge-sustaining mode.

• Regular hybrid electric vehicles cannot be externally charged.
• Hybrid vehicles with batteries that can be charged externally to displace some or all of their internal combustion engine power and gasoline fuel are called plug-in hybrid electric vehicles (PHEV), and are BEVs during their charge-depleting mode.

All-electric and plug-in hybrids are off-vehicle charge capable. (“OVCC” or pluginable), which means their batteries can be charged from an off-vehicle electric energy source that cannot be connected or coupled to the vehicle while the vehicle is being driven (2)

Sources:

(1) Mark Z. Jacobson and Mark A. Delucchi: Evaluating the Feasibility of a Large-Scale Wind, Water, and Sun Energy Infrastructure

(2) http://en.wikipedia.org/wiki/Battery_electric_vehicle

the BMD concept involves fitting a mathematical model to dose-response data. The BMD is defined as the dose causing a predetermined change in response.

Source: REACH

the BMD concept involves fitting a mathematical model to dose-response data. The BMD is defined as the dose causing a predetermined change in response.
The BMD10 Benchmark-dose associated with a 10% response (for tumours upon lifetime exposure after correction for spontaneous incidence, for other effects in a specified study.
The BMDL10 is the lower 95% confidence interval of a Benchmark-dose representing a 10% response (e.g., tumour response upon lifetime exposure), i.e. the lower 95% confidence interval of a BMD10. (Source: REACH Glossary)

community of sediment dwelling organisms, named also benthos.

the Best Practicable Environmental Option BPEO Twelfth Report, FEB 1988, Cm 310, is a set of procedures adopted by Great Britain with the goal of managing waste and other environmental concerns. According to the Royal Commission on Environmental Pollution, BPEO "emphasises the protection and conservation of the environment across land, air and water. The BPEO procedure establishes for a given set of objectives, the option that provides the most benefits or the least damage to the environment, as a whole, at acceptable cost, in the long term as well as in the short term."
Source: Wikipedia, http://en.wikipedia.org/wiki/Best_practicable_environmental_option

a microbial, plant or animal species whose presence, abundance, and health reveal the general condition of its habitat. The specific chemical, biochemical or genetical characteristic or molecule of these species can also function and bio-indicator. These bio-indicators can be used as measured endpoints in ecological surveys or ecotoxicological test methods.

Bioaccumulative and very bioaccumulative substances are those, which are able to concentrate in the body of living organisms of microbial cells, plants or animals, including man. Bioconcentration is measured related to the environment and is quantitatively characterized by the BCF = bioconcentration factos, which is the ratio of two concentrations, the concentration in the organism or organ and the concentration in the environmental compartment.

BCF Plant = Cplant/ Csoil, or BCF Fish is Cfish/Cwater. Bioaccumulation of certain substances, e.g. hydrofobic organic substances in liver of adipose tissue or inorganic substances such as toxic metals Pb, Cd, or mercury in plant shoot and leaves leads to the toxication of the food-chain and biomagnification along the food-chain.

According to REACH regulation a substance fulfils the bioaccumulative criterion when:
– the bioconcentration factor (BCF) is higher than 2 000.
The assessment of bioaccumulation - according to REACH methodology - shall be based on measured data on bioconcentration in aquatic species. Data from freshwater as well as marine water species can be used. This kind of aquatic bioconcentration of the substances serves as basis to declare a substance PBT (Bioaccumulative, Persistent and Toxic), which is a priority risk category of REACH.

Directive 98/8/EC of the European Parliament and of the Council on the placing on the market of biocidal products was adopted in 1998. According to the Directive, Member States had to transpose the rules before 14 May 2000 into national law.

The Commission adopted the original proposal for the Directive in 1993. Directive 91/414/EEC on plant protection products, adopted in 1991, served as a model for the new Directive.

The Biocidal Product Directive aims to harmonise the European market for biocidal products and their active substances. At the same time it aims to provide a high level of protection for humans, animals and the environment.

biocides are defined in Article 2 (1) of the Biocidal Products Directive (98/8/EC) as:
"Active substances and preparations containing one or more active substances, put up in the form in which they are supplied to the user, intended to destroy, deter, render harmless, prevent the action of, or otherwise exert a controlling effect on any harmful organism by chemical or biological means."
Note, however, that many substances or preparations which meet this definition are excluded from the Biocidal Products Directive on the basis of being covered by other legislation such as the Plant Protection Products Directive (91/414/EEC) and many other Directives relating to veterinary medicines, proprietary medicinal products etc. Therefore, for a complete definition of a biocidal products you should consult the Biocidal Products Directive and its associated guidance.
In general terms, the scope of the Biocidal Products Directive is very wide, covering 23 different product types. This includes disinfectants for home and industrial use, preservatives for manufactured and natural products, non-agricultural pesticides for use against insects, rodents and other vertebrates and specialised products such as embalming/taxidermist fluids and antifouling products. A full list of product types is in Annex V of the BPD.
Under Article 15 (2) of the REACH Regulation, active substances which are regulated as biocides are regarded as being already registered under REACH.
Directive 98/8/EC, Articles 1 and 2.; REACH Article 15 (2).

a bioconcentration+Factor" target="_blank">bioconcentration Factor L/kg can either be expressed as the ratio of the concentration of a substance in an organism to the concentration in water once a steady state has been achieved static BCF, or, on a non-equillibrium basis, as the quotient of the uptake and depuration rate constants dynamic BCF. Static and dynamic BCFs can be equally used for regulatory purposes. The parameter gives an indication of the accumulation potential of a substance. Source: REACH Glossary