Glossary

All A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Term Definition
Absorption

Latin absorptio - engulf. I means to incorporate something into something.

Acute

Denotes a sudden, rapid, short-term effect (e.g. a fast occurring toxic effect).

ADI

Short for Acceptable daily intake, is a measure of the amount of a specific substance (originally applied for a food additive, later also for a residue of a veterinary drug or pesticide) in food or drinking water that can be ingested (orally) on a daily basis over a lifetime without an appreciable health risk.

Aerosols

General term for mixtures of gases (e.g. air) that contain suspended solid or liquid particles (so-called particulate matter), which are approximately 1 nm to 10 μm in diameter. Sea salt aerosols, for example, are formed as sea water droplets that are dispersed into the atmosphere by wind evaporate to leave sea salt particles.

AFM

Short for atomic force microscopy. The AFM tip scans the sample line for line. Due to repulsion between needle and sample, a movement of the tip is detected. A three dimensional image can be simulated.

Agglomerates

Accumulations of weakly bound particles or aggregates or of compounds of these, whose resulting surfaces are similar to the sum of surfaces of the individual components. Agglomerates are held together by weak forces, for example Van der Waals forces or simple physical hooks. Agglomerates are referred to as secondary particles, while the unbound particles are known as primary particles.
See also ISO/TS 27687:2008 (E), International Organization for Standardization.

Aggregates

Solidly bound or molten particles, whose resulting surface may be much smaller than the sum of the calculated surfaces of the individual components. Aggregates are held together by strong forces such as covalent bonds or forces caused by sintering or complex physical hooking. Aggregates, just as agglomerates, are referred to as secondary particles.
See also ISO/TS 27687:2008 (E), International Organization for Standardization.

Alveoli

From Latin alveolus, "little cavity". Thin-walled, tiny air sacs, located at the ends of the smallest airways in the lungs (the bronchioles) where the exchange of oxygen and carbon dioxide takes place.

Antigene

Describes a foreign substance that when introduced into the body stimulates the production of an antibody. Many bacteria contain antigens. Toxins, viruses, blood cells or cells from foreign transplants can act as antigens as well.

Antioxidant

Any substance that prevents or reduces free-oxygen-radicals, which attack other molecules and modify their chemical structure. Antioxidants are commonly used as preservatives in food or cosmetics. Well-known antioxidants include vitamins A, C, and E.

Apoptosis

Physiological or programmed cell death. In apoptosis only individual cells are affected generally and these react to internal signals (e.g. adjacent cells) or external stress situations. At the beginning of this process the cell nucleus, cytoplasm and mitochondria are shrinking; the cell membrane remains undamaged, so that no inflammatory reaction occurs. The biochemical indicator of apoptosis is the fragmentation of DNA. Along with proliferation the apoptosis is the common instrument to stabilise the cell count.

Aspiration

From lat. aspirare - to breath. Describes in animal experiments the administration of (particle) suspensions in the nasopharynx with a hollow needle. The liquid droplet is injected with some pressure, so that the suspension can pass into the lung. This procedure is related to the instillation.

BET

Description of a method (Brunauer-Emmett-Teller) for the analysis technique of sizing surfaces by means of gas adsorption.

Bioaccumulation

Greek for bios - life and Latin for accumulare - pile up, accumulate; is the accumulation of a substance in an organism by absorption from the surrounding medium (e.g. water in fish) and through food.

Bioavailability

Refers to the rate and extent to which a substance is absorbed unchanged from the environment or the gastrointestinal tract into the body. The amount taken up does not necessarily correspond to the amount present in food or in the environment of a living organism.