General Directorate of Environmental Management Chemicals Management Department
General Directorate of Environmental Management Chemicals Management Department
POPs Dictionary





Conference of Parties of the Stockholm Convention


European Commission


European Union


Global Environment Facility


North Atlantic Treaty Organization


Non Governmental Organization


National Implementation Plan


Organization for Economic Co-operation and Development


Operational program


POPs elimination network


Persistent Organic Pollutants


Project Steering Committee


Pollutants Release and Transfer Register


Research Centre for Toxic Compounds in the Environment, Masaryk University, Brno, Czech Republic


Strategic Approach for International Chemicals Management


Stockholm Convention on POPs


United Nations


United Nations Development Programme


United Nations Environment Programme


United Nations Industrial Development Organization


United Nations Institute for Training and Research


World Health Organisation

An object which during production is given a special shape, surface or design, which determines its function to a greater degree than does its chemical composition. Examples of articles are a car, battery, computer, telephone, printer, clothes, and refrigerator. Articles can contain liquids (e.g. car: brake fluid) and gases (e.g. refrigerator: compressed cooling gas).

Chemical good/good

A substance or a mixture/preparation or an article.

Chemical identity

A name that will uniquely identify a chemical. This can be a name that is in accordance with the nomenclature systems of the International Union of Pure and Applied Chemistry (IUPAC) or the Chemical Abstracts Service (CAS), or a technical name.

Chemical product/product[1]

A chemical substance and/or mixture/preparation of chemical substances with certain percentages or percentage ranges of the chemical substances.

Chemical substance/chemical/substance

Chemical elements and their compounds in the natural state or obtained by any production process, including any additive necessary to preserve the stability of the product and any impurities deriving from the process used, but excluding any solvent which may be separated without affecting the stability of the substance or changing its composition.

Commercial OctaBDE or c-OctaBDE

Mixtures of polybrominated diphenyl ether congeners in which the main components are hexabromodiphenyl ether, heptabromodiphenyl ether, octabromodiphenyl ether, and nonabromodiphenyl ether.

Commercial PentaBDE or c-PentaBDE

Mixtures of polybrominated diphenyl ether congeners in which the main components are tetrabromodiphenyl ether, pentabromodiphenyl ether, and hexabromodiphenyl ether.

Common name

A name that is given to a chemical to be able to communicate more easily, especially with the public, than through the often complicated systematic chemical name.


Depending on the number and position of the chlorine atoms in the biphenyl molecule, 209 isomers and homologue chlorine biphenyls are theoretically possible. A single compound from this group is called PCB congener.


Disposal means any operation specified in Annex IV to the Basel Convention[2].

Generic name

A name that is not specific for a chemical substance, but describes a class of chemicals. A generic name is used by industry, for example, to protect confidential business information when the identity of the chemical should not be revealed through the chemical identity.



Listed polybrominated diphenyl ethers (PBDEs) or POP-PBDEs

Polybrominated diphenyl ethers listed as POPs in Annex A of the Stockholm Convention –tetrabromodiphenyl ether and pentabromodiphenyl ether – and – hexabromodiphenyl ether and heptabromodiphenyl ether.

A mixture or a solution composed of two or more substances in which they do not react.


Polychlorinated biphenyls


Polychlorinated dibenzo-p-dioxins or shortly dioxins


Polychlorinated dibenzofurans


Any substance or mixture of substances intended for preventing, destroying, or controlling any pest. Pests include vectors of human or animal disease, unwanted species of plants or animals causing harm during or otherwise interfering with the production, processing, storage, transport, or marketing of food, agricultural commodities, wood and wood products, or animal feedstuffs. A pesticide is also any substance administered to animals for the control of insects, arachnids, or other pests in or on their bodies or substances intended for use as a plant growth regulator, defoliant, desiccant, or agent for thinning fruit or preventing the premature fall of fruit. The term can also be used for substances applied to crops either before or after harvest to protect the commodity from deterioration during storage and transport

PFOS related chemicals

Chemicals that contain the structural element PFOS in their molecular structure as they are and were produced with perfluorooctane sulfonic acid (PFOS), its salts or perfluorooctane sulfonyl fluoride (PFOSF) as an intermediate or starting material.

A reserve of a chemical as a substance and/or preparation, and/or of articles containing the chemical accumulated within a country that are still allowed to be used under the Convention. If stockpiles are no longer to be used according to any specific exemption specified in Annex A or acceptable purpose specified in Annex B and if they are not allowed to be exported according to paragraph 2 of Article 3 they shall be deemed to be waste.

Trade name

A name that is given to a chemical, a mixture or an article by the company that markets/ supplies it. The trade name normally specifically identifies the chemical, mixture, or article and sometimes gives information on the company.

Unintentional trace contaminant

A chemical substance, mixture, or article that contains unintentionally a POP listed in Annex A or B in a concentration higher than a trace contaminant is regulated as POPs


Substances or objects which are disposed of or are intended to be disposed of or are required to be disposed of by the provisions of national law.


European agreement on the international road transport for hazardous goods


Best Available Technologies


Best Environmental Practices


Equipment or unit to supply lagging kilovars for power factor correction of an electric system; some capacitors were manufactured with PCB as cooling fluid

Capacitor Bank (General)

Practically there are three different ways of power factor (PF) correction: Capacitors for "individual" PF-correction; the capacitor is directly connected to the terminals of an equipment (motors, welding machine etc.) producing the "lagging kilovars"

Capacitor Bank (LV)

Capacitors for "group" PF- correction; the capacitor(s) is (are) connected to the LV-busbar of a transformer station, which feeds a number of consumers with individual motors, welding machines etc

Capacitor Bank (MV)

Capacitors for "central" PF-correction; Large capacitor installation connected to the Middle- or High Voltage busbars of a substation where many individual electrical appliances (motors etc.) of various size operate at different times and periods.

Closed systems

Capacitors and transformers, where the PCB itself is in completely closed containers; PCBs rarely emit from closed systems (in good condition)

Cooling fluid

Dielectric fluid


Environmentally Sound Management


Gas chromatography/mass spectrometry


High voltage


Low voltage (230/400 V)


Medium voltage (Normally in the range between 11 and 66kV)

Open systems

Applications where PCB is consumed during its use or not disposed of properly after its use or after the use of the products that contain PCB; open systems emit PCB directly in the environment (e.g. softeners in PVC, neoprene and other rubbers containing chloride).

Primary sources

A product to which PCB was added voluntarily to influence the product’s characteristics (e.g. cooling fluids for transformers like Sovol, Sovtol, Askarel, Pyralene, Clophen, etc.); Such products emit PCB continuously.

Secondary sources

A product that originally was free of PCB, but later contaminated by PCB emitting from primary sources (e.g. by emission from primary sources or use of contaminated pumps, hoses, etc.). Such products also emit PCB.


Equipment used to increase or reduce voltage; PCB containing transformers are usually installed in sites or buildings where electricity is distributed


Ultra violet


Acceptable Daily Intake. The daily intake of a chemical which, over a lifetime, appears to be without appreciable risk, on the basis of all the facts known at the time. It is expressed in milligrams per kilogram of body weight per day (mg kg-1 bw day-1).

Adverse Effect

A change in morphology, physiology, growth,  development or life span of an organism which results in an impairment of its functional capacity or impairment of its capacity to compensate for additional stress, or an increase in its susceptibility to the harmful effects of other environmental influences.


Any chemical, physical, biological or social substance or factor being assessed, unless otherwise noted.

Applied Dose

Amount of an agent presented to an absorption barrier and available for absorption.


Benchmark Dose. The dose associated with a given incidence (e.g., 1%, 5% or 10% incidence) of effect, the Benchmark Risk, based on the best-fitting dose-response curve.


The ratio of the systemic dose to the applied dose.


Chemical, biological or physical cancer-causing agent.


The origin, causation and development of tumours. The term applies to all forms of tumours (e.g., benign and malignant).


The ability to produce tumours, which may be benign or malignant)

Chronic toxicity

The ability to produce an adverse effect which persists over a long period of time, whether or not it occurs immediately upon exposure to a contaminant or is delayed, or an effect which is only induced by prolonged exposure to a contaminant.


Weight assigned by the evaluator to the quality of the information available (high, medium or low confidence) to indicate that a contaminant possesses certain toxicological properties.

Confidence Limits

A range of values determined by the degree of presumed random variability in a set of data, within which the value of a parameter, e.g., the mean, lies, with a specified level of confidence or probability (e.g. 95%). The confidence limit refers to the upper or lower value of the range.

Critical Effect(s)

The adverse effect judged to be the most important for setting an acceptable human intake or exposure. It is usually the most sensitive adverse effect, i.e., that with the lowest effect level, or sometimes a more severe effect, not necessarily having the lowest effect level.


Of the skin, through or by the skin.


A stated quantity or concentration of a contaminant to which an organism is exposed over a continuous or intermittent duration of exposure. It is most commonly expressed as the amount of test contaminant per unit weight of test animal (e.g., mg kg-1 bw).

Dose-response assessment

Determination of the relationship between the magnitude of the dose or level of exposure to a contaminant and the incidence or severity of the associated adverse effect.

Dose-response relationship

The correlative association existing between the dose administered and the response (effect) or spectrum of responses that is obtained. The concept expressed by this term is indispensable to the identification, evaluation, and interpretation of most pharmacological and toxicological responses to contaminants.


An observable or measurable biological event used as an indicator of the effect of a contaminant on a biological system (cell, organism, organ etc.).

Environmental health

Those aspects of human health determined by physical, chemical, biological and social factors in the environment. Environmental health practice covers the assessment, correction, control and prevention of environmental factors that can adversely affect health, as well as the enhancement of those aspects of the environment that can improve human health.

Environmental monitoring

The monitoring of the concentration of contaminants in the physical environment of air, water, soil and food.


The study of the distribution and determinants of health-related states or events in specified populations, and the application of that study in the control of health problems


Contact of a contaminant, physical or biological agent with the outer boundary of an organism, e.g., Inhalation, ingestion or dermal contact.

Exposure assessment

The estimation (qualitative or quantitative) of the magnitude, frequency, duration, route and extent (for example, number of organisms) of exposure to one or more contaminated media for the general population, for different subgroups of the population, or for individuals.

Exposure route

The way a contaminant enters an organism after contact e.g., by ingestion, inhalation, or dermal absorption.


For dose-response curves, an estimate of the response at a point outside the range of the experimental data. Also refers to the estimation of a response in different species or by different routes than that used in the experimental study of interest.


Agents whose direct activity is the alteration of the information encoded in genetic material.

Genotoxic carcinogen

A contaminant which induces tumours via a mechanism involving direct damage to DNA.


A broad term describing the ability to produce damage to the genetic material (DNA) of cells or organisms.

Guidance values

Values such as concentrations in air or water, which are derived after the appropriate allocation of Tolerable Intake (TI) to the various possible media of exposure.


The capacity of a contaminant to produce a particular type of adverse health or environmental effect,

Hazard identification

The identification, from animal and human studies, in vitro studies and structure-activity relationships, of adverse health effects associated with exposure to a contaminant.


Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.

Health risk assessment

The process of estimating the potential impact of a chemical, biological, physical or social agent on a specified human population system under a specific set of conditions and for a certain timeframe.

Health risk management

The process of evaluating alternative actions, selecting options and implementing them in response to Human Health Risk Assessment. The decision-making will incorporate scientific, technological, social, economic and political information. The process requires value judgements, e.g., on the tolerability and reasonableness of costs.


The ability to produce an adverse effect on the functioning of organs and cells involved in immune competence.


The quantity of a contaminant that, when applied directly to test organisms, via inhalation, oral or dermal exposure is estimated to be fatal to 50% of those organisms under the stated conditions of the test. The number of microorganisms of a particular species that are fatal in 50% of the host organisms.


Lowest Observed Effect Level. The lowest concentration or amount of a contaminant, found by experiment or observation, that causes alterations in the morphology, functional capacity, growth, development or life span of target organisms.


Lowest Observed Adverse Effect Level. The lowest concentration or amount of a contaminant, found by experiment or observation, that causes adverse alterations in the morphology, functional capacity, growth, development or life span of target organisms.


Covering the average life span of an organism (e.g., 70 years for humans).


A contaminant that is the product of the biochemical alteration of the parent contaminant in an organism.


The No-Observed-Adverse-Effect Level is the highest dose of a contaminant at which no toxic (i.e., adverse) effects are observed.


The “No-Observed-Effect Level” or “No-Observable-Effect Level” (NOEL) is the highest dose of a contaminant administered to a group of experimental animals at which there is an absence of observable effects on their morphology, functional capacity, growth, development or life span, which are observed or measured at higher dose levels used in the study. The NOEL is expressed in milligrams of contaminant per kilogram of body weight per day (mg kg-1 bw day-1) or, in a feeding study, in ppm in food (converted to mg/kg bw of contaminant intake by measured or estimated food intake over the period of the study).

Reproductive toxicity

The ability to produce an adverse effect on any aspect of reproductive capacity, function or outcome. It includes effects on the embryo, fetus, neonate and prepubertal organism and on adult reproductive and neuroendocrine systems.


Reference Dose (RfD). An estimate (with uncertainty factors spanning perhaps an order of magnitude) of the daily exposure (mg kg-1 bw day-1) to the general human population (including sensitive sub-groups) that is likely to be without an appreciable risk of deleterious effects during a life time of exposure. It is derived from the NOAEL or the by applying uncertainty factors that reflect various types of data used to estimate RfD and an additional modifying factor, which is based on professional judgement of the entire data base of the contaminant.


The probability that, in a certain timeframe, an adverse outcome will occur in a person, group of people, plants, animals and/or the ecology of a specified area that is exposed to a particular dose or concentration of a contaminant, i.e., it depends on both the level of toxicity of the contaminant and the level of exposure.

Risk assessment

The process of estimating the potential impact of a chemical, physical, microbiological or psychosocial hazard on a specified human population or ecological system under a specific set of conditions and for a certain timeframe

Risk management

The process of evaluating alternative actions, selecting options and implementing them in response to Risk Assessments. The decision-making will incorporate scientific, technological, social, economic and political information. The process requires value judgements, e.g. on the tolerability and reasonableness of costs.


The ability to produce a structural malformation or defect in an embryo or fetus.


The lowest dose or exposure level which will produce a toxic effect and below which no toxicity is observed.

Threshold dose

The lowest dose which produces an effect and below which no biological effect occurs.


Tolerable Daily Intake. An estimate of the intake of a contaminant which can occur over a lifetime without appreciable health risk. The term “tolerable” daily intake is used when the contaminant is a potential food or environmental contaminant. Whilst exposure should not occur, a TDI is an established health limit below which lifetime exposure should not have any adverse health effects.“Acceptable Daily Intake” and “Reference Dose”.


Tolerable Weekly Intake. The TI expressed as a weekly amount


The quality or degree of being poisonous or harmful to plant, animal or human life.


The lack of knowledge about the correct value, e.g. a specific exposure measure or estimate

Uncertainty factor

A numerical factor applied to the no-effect level to derive an exposure level considered to be without appreciable risk to health (the NEL is divided by the uncertainty factor). The magnitude of the uncertainty factor depends on the nature of the toxicity observed, the quality of the toxicological data available, and whether the effects were observed in humans or animals.


Measurable factors that differ e.g. height is variable across populations. The major types of variability are temporal, spatial and inter-individual. They may be discrete (e.g. albinism) or continuous (e.g., body weight). It may be readily identifiable (e.g., presence of albinism) or difficult to identify (e.g., ability to detoxify a particular contaminant metabolite).



[1]The term product is sometimes used to refer to chemicals, mixtures and articles


[2] Basel Convention on the control of transboundary movements of hazardous wastes and their disposal is an international treaty adopted on 22 March 1989,