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Glossary over Nanotechnologies


To take up and hold (a gas, liquid, or dissolved substance) in a thin layer of molecules on the surface of a solid substance. (Source: US EPA Acid Rain Glossary  )



An aerosol is a collection of microscopic particles, solid or liquid, suspended in a gas.

In the context of air pollution, an aerosol refers to fine particulate matter, that is larger than a molecule, but small enough to remain suspended in the atmosphere for at least several hours.

The term aerosol is also commonly used for a pressurized container (aerosol can) which is designed to release a fine spray of a material such as paint. It has also come to be associated, erroneously, with the gas (propellant) used to expel materials from an aerosol can. (Source: GreenFacts )



Refers to surrounding environmental conditions such as temperature or noise.

In the case of air, ambient air often refers to outdoor air as opposed to indoor air. (Source: GreenFacts)


The mass of air surrounding the Earth.

The atmosphere consists of nitrogen (78%), oxygen (21%), and traces of other gases such as argon, helium, carbon dioxide, and ozone.

The atmosphere plays an important role in the protection of life on Earth; it absorbs ultraviolet solar radiation and reduces temperature extremes between day and night. (Source: GreenFacts)



The smallest particle of an element that still conserves the chemical properties of that element. Atoms are composed of electrons, protons, and neutrons. (Source: GreenFacts)


Bioaccumulation is used to describe the increase in concentration of a substance in an organism over time.

Bioaccumulative substances tend to be fat soluble and not to be broken down by the organism. (Source: GreenFacts )



A biochip refers to a collection of miniaturized test sites, or microarrays, arranged on a solid substrate that permits many tests to be performed at the same time in order to achieve higher throughput and speed.

Like a computer chip that can perform millions of mathematical operations in one second, a biochip can perform thousands of biological reactions, such as decoding genes, in a few seconds.

Biochips helped to dramatically accelerate the identification of the estimated 80,000 genes in human DNA.

In addition to genetic applications, biochips are being used in toxicological, protein, and biochemical research. (Source: Digital Bio Technology Biochips on the rise  )


A biomolecule is a chemical compound found in living organisms. These include chemicals that are composed of mainly carbon, hydrogen, oxygen, nitrogen, sulfur and phosphorus.

Biomolecules are the building blocks of life and perform important functions in living organisms. (Source: Biomolecule  )


Blood-brain barrier

A protective barrier between brain blood vessels and brain tissues that allows blood to flow freely to the brain but prevents most substances in the bloodstream from reaching the brain cells.

It protects the brain from the effect of many harmful substances but makes it difficult to deliver drugs to the brain. (Source: GreenFacts)

Bottom-up vs Top-down (in the context of nanoparticle formation)

There are two approaches for the manufacturing of nanomaterials:

  • The “top-down” approach, which involves the breaking down of large pieces of material to generate the required nanostructures from them.
  • The “bottom-up” approach, which implies assembling single atoms and molecules into larger nanostructures.

Any one of a group of diseases that occur when cells in the body become abnormal and have the potential to spread and establish growth in nearby tissues and other parts of the body (malignancy). (Source: GreenFacts )


Catalytic converter

Emissions control device, incorporated into an automobile’s exhaust system, that reduce the levels of hydrocarbons (HC), carbon monoxide (CO), and - in more recent designs - nitrogen oxides (NOx) emitted to the air by gasoline-powered vehicle engines.



The basic subunit of any living organism; the simplest unit that can exist as an independent living system. There are many different types of cells in complex organisms such as humans, each with specific characteristics. (Source: GreenFacts)


Cell membrane

The cell membrane is a fine structure that envelops a cell, separating the content of the cell from its surroundings.

It regulates the substances that can enter and leave the cell.

The membrane consists of a double layer of lipids in which proteins are embedded. (Source: GreenFacts)


An electric charge (q or Q) is the quantity of unbalanced electricity in an object (either positive or negative). It is interpreted as an excess or deficiency of electrons. Matter that possesses a charge is influenced by and produces electromagnetic fields.

Electrons, by convention have an elementary charge of -1. Ions are either positively or negatively charged. The unit of measurement of the charge of an object is the coulomb, which represents 6.24 x 1018 elementary charges. (Source: GreenFacts)


Occurring over a long period of time, either continuously or intermittently; used to describe ongoing exposures and effects that develop only after a long exposure. (Source: US EPA Thesaurus  )

Circulatory system

The system that contains the heart and the blood vessels and moves blood throughout the body. This system helps tissues get enough oxygen and nutrients, and it helps them get rid of waste products. The lymph system, which connects with the blood system, is often considered part of the circulatory system. (Source: NCI Dictionary of cancer terms  )



A material made up of two or more elements combined in a fixed ratio. (Source: CoRIS glossary  )



DNA constitutes the molecules inside cells that carry genetic information and pass it from one generation to the next. (Source: NCI dictionary  )



The amount of a substance to which a person is exposed over some time period. Dose is a measurement of exposure. Dose is often expressed as milligram (amount) per kilogram (a measure of body weight) per day (a measure of time) when people eat or drink contaminated water, food, or soil. In general, the greater the dose, the greater the likelihood of an effect. An "exposure dose" is how much of a substance is encountered in the environment. An "absorbed dose" is the amount of a substance that actually got into the body through the eyes, skin, stomach, intestines, or lungs. (Source: ATSDR Glossary of Terms  )

Electron microscopy

The technique used to produce an enlarged image of a tiny object that utilizes an electron microscope, an instrument that uses a beam of electrons focused by an electron lens.

This type of microscopy is necessary when items or features are too small to be imaged by light. In this case, the image is created by the bending/reflection of an electron beam rather than a light beam. (Source: New York Sea Grant Brown Tide Research Initiative Terms  )


Any stable mixture of two liquids that naturally do not mix together or dissolve in each other (such as oil and water), where one liquid (in the form of fine droplets or globules) is dispersed in the other. (Source: GreenFacts)

Epidemiological studies

Studies on human populations, which attempt to link human health effects (e.g. cancer) to a cause (e.g. exposure to a specific chemical). (Source: GreenFacts)



Contact of the cells of an organism with a substance, micro-organism or radiation. In the case of humans, this may involve contact with a substance or agent by swallowing, breathing, or through the skin or eyes. Exposure may be short-term [acute exposure], of intermediate duration, or long-term [chronic exposure].

Exposure can be divided into external and internal.

External exposure refers to the whole dose to which an organism is exposed.

Internal exposure refers only to that fraction of the initial chemical dose that is absorbed and distributed throughout the body via systemic circulation. (Source: GreenFacts)



The embryo is referred to as a foetus after it has reached a certain stage of organ development (in humans this is eight weeks after conception). (Source: CSIRO Glossary of terms  )

Fossil fuel(s)

A general term for buried combustible geologic deposits of organic materials, formed from decayed plants and animals that have been converted to crude oil, coal, natural gas, or heavy oils by exposure to heat and pressure in the Earth's crust over hundreds of millions of years. (Source: US EPA Glossary of Climate Change terms  )

Gene Therapy

Treatment of a disease by replacing, manipulating, or supplementing defective genes with healthy ones. (Source: GreenFacts)


The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein. (Source: NHGRI Talking Glossary of Genetic Terms  )

Immune system

The immune system is a network of cells, tissues, and organs that work together to defend the body against attacks by “foreign” invaders. (Source: NIAID Immune System   )



Inflammation is the reaction of living tissues to infection, irritation or other injury. (Source: GreenFacts)



The act of swallowing something through eating, drinking, or mouthing objects. A hazardous substance can enter the body this way. (Source: ATSDR Glossary of Terms  )


The act of breathing.

A hazardous substance can enter the body by inhaling an airborne substance or contaminant in the form of gas, fumes mists, vapors, dusts, or aerosols. Once inhaled, contaminants can be deposited in the lungs and/or transported into the blood. (Source: GreenFacts)


The larynx (voice box) is the upper end of the trachea (windpipe) that contains the vocal cords. It is the organ of voice production.

The larynx is the cornerstone of the aerodigestive system. It is related to three functions:

  • deglutition
  • respiration
  • phonation
(Source: GreenFacts)

Mass Spectrometer

The mass spectrometer is an instrument which can measure the masses and relative concentrations of atoms and molecules. It makes use of the basic magnetic force on a moving charged particle. (Source: HyperPhysics Mass Spectrometer  )


The conversion or breakdown of a substance from one form to another by an enzyme. (Source: GreenFacts, based on ATSDR Glossary of Terms )



Any living organism that is too small to be seen by the naked eye such as bacteria, viruses, protozoa, single-celled algae, and many types of fungi. (Source: GreenFacts)


Unit of length equal to one millionth of a metre. (Source: GreenFacts)


A molecule is the smallest part of any chemical compound composed of two or more atoms and which has the qualities of that substance and can exist alone in a free state. As an example, a molecule of water (H2O) consists of two atoms of hydrogen and one of oxygen. (Source: GreenFacts, based on Helios Glossary   )

Mucous membrane

The moist layer of tissue lining the digestive, respiratory, urinary and reproductive tracts - all the body cavities with openings to the outside world except the ears. (Source: Medical dictionary   )


Material with one or more external dimensions, or an internal structure, at nanoscale and which could exhibit novel characteristics compared to the same material at a larger scale. (Source: based on SCENIHR's opinion on the  appropriateness of existing methodologies to assess the potential risks associated with engineered and adventitious products of nanotechnologies )



Unit of length equal to one millionth of a millimetre (10-9 m). (Source: GreenFacts)


Particle with one or more dimensions of the order of about 100 millionth of a millimetre (100 nm) or less.

(Note: In the SCENIHR  opinion on the appropriateness of existing methodologies to assess the potential risks associated with engineered and adventitious products of nanotechnologies, nanoparticles are considered to have two or more dimensions at the nanoscale) (Source: GreenFacts )


Having one or more dimensions of the order of 100 nm or less. (Source: GreenFacts)


The study of phenomena and manipulation of materials at nanoscale, where properties differ significantly from those at a larger scale. (Source: based on SCENIHR’s opinion on the  appropriateness of existing methodologies to assess the potential risks associated with engineered and adventitious products of nanotechnologies )


Structure with one or more dimensions at the nanoscale. (Source: GreenFacts)


Nanotechnology is the science of designing, producing, and using structures and devices having one or more dimensions of about 100 millionth of a millimetre (100 nanometres) or less. (Source: GreenFacts)


Olfactory nerve

The olfactory nerve is the part of the nervous system transmitting the sense of smell from the nose to the brain. It courses along the base of the frontal lobes of the brain and perforates through the base of the skull and rests inside the roof of the nose. (Source: GreenFacts, based on Congress of Neurological Surgeons Crranial Nerves   )

Oxidative stress

The term “oxidative stress” refers to the presence of excessive levels of highly reactive molecules called free radicals in the cell or a lack of molecules called antioxidants that can eliminate those free radicals. (Source: Charles S. Lieber  Alcohol and Hepatitis C )


Particulate matter

Sum of all microscopic solid and liquid particles, of human and natural origin, that remain suspended in a medium such as air for some time. These particles vary greatly in size, composition, and origin, and may be harmful.

Particulate matter may be in the form of fly ash, soot, dust, fog, fumes etc. (Source: GreenFacts)



A polymer is a high-molecular-weight organic compound, natural or man-made, consisting of many repeating simpler chemical units or molecules called monomers.

Examples of natural polymers are proteins (polymer of amino acids) and cellulose (polymer of sugar molecules).

An example of synthetic polymer is PVC (a polymer of vinyl chloride). (Source: GreenFacts)



A large molecule composed of one or more chains of amino acids in a specific order, formed according to genetic information.



Relating to, or associated with the lungs. (Source: GreenFacts)

Respiratory tract

The organs that are involved in breathing.

These include the nose, throat, larynx, trachea, bronchi, and lungs. Also known as the respiratory system. (Source: St. Jude Children's Research Hospital Glossary   )


Scientific Committee on Emerging and Newly Identified Health Risks

The Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) was set up in 2004 by the European Commission to provide the Commission with unambiguous scientific advice on the safety of a series of issues requiring a comprehensive assessment of the risks, such as new technologies, medical devices, etc.

The SCENIHR advice is intended to enable risk managers to take the adequate and required actions in order to guarantee consumer safety or public health.

The SCENIHR addresses questions concerning emerging or newly-identified risks and on broad, complex or multi-disciplinary issues requiring a comprehensive assessment of risks to consumer safety or public health and related issues not covered by other Community risk- assessment bodies.

The Scientific Committee on Emerging and Newly Identified Health Risks is composed of a maximum of 13 members, but for any specific question may enlist the support of up to six associated members selected on the basis of their expertise. There is also a reserve list made up of candidates found suitable for a position in a Scientific Committee but not appointed. The members of the SCENIHR are appointed on the basis of their skills and experience in the fields in question, and consistent with this a geographical distribution that reflects the diversity of scientific problems and approaches in the European Union (EU). The experts' term of office is three years and is renewable for a maximum of three consecutive times. In agreement with the Commission, the Scientific Committees may turn to specialised external experts.

The SCENIHR complies with the principles of independence, transparency and confidentiality. The members therefore make a declaration of commitment to act in the public interest and a declaration of interests; requests for opinions, agendas, minutes and opinions are published; work and publications are done with regard to the need for commercial confidentiality. (Source: SCENIHR pages  )


A substance is soluble if it dissolves in certain fluids. The fluid [gas or liquid] (present in excess) is called the solvent and the substance dissolved in it is called the solute which together form a solution. The process of dissolving is called solvation. A solution that can not hold any more solute is said to be saturated. (Source: GreenFacts )


An organ that is part of the immune system. The spleen is a storage site for lymphocytes (white blood cells important in immunity and defense against infection), it filters the blood, stores blood cells, and destroys old blood cells.

It is located on the left side of the abdomen near the stomach.

Immune reactions can occur in the spleen. (Source: GreenFacts, based on St. Jude Children’s Research Hospital Medical terminology & drug database  )



A group of cells joined to perform a set of functions. (Source: GreenFacts)


Able to poison or harm an organism. Toxic substances can cause adverse health effects. (Source: GreenFacts)


The capacity or property of a substance to cause adverse effects. (Source: GreenFacts)



An abnormal mass of tissue resulting from uncontrolled and excessive cell division.

Tumours can be either benign (localised, without the invasion of other tissues) or malignant (showing progressive invasion of other tissues). (Source: GreenFacts)

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