1R6F / 3R4F
Standard reference cigarettes widely used in tobacco research.

Addiction
Where a product is enjoyed regularly with known harm and where it can be difficult to quit use e.g. alcohol or cigarette smoking.

Aerosol
A suspension of small liquid or solid particles in a gas (air). For example, vape products produce an aerosol from e-liquid. In non-scientific vaping communication materials, we sometimes refer to aerosol as ‘vapour’ to mitigate consumer confusion.

AMES validated assay
An in-vitro experiment which can be used to assess the mutagenicity (see Mutagenic) of a substance in bacteria.

Atomiser
An assembly of coil and wicking material to which power is supplied, and which heats an e‐liquid to form an aerosol.

Biomarker of effect
Effect refers to the body’s reaction to a stimulus or substance. A biomarker of effect is used in the assessment of health risk. A biomarker of effect demonstrates the effect of a chemical on a physiological process and is an indicator of a possible health problems.

Biomarkers of exposure
Measurable constituents resulting from exposure to a substance, e.g. cigarette smoke. This may be the substance itself, or via measuring metabolites in the urine, blood or saliva. e.g. nicotine’s metabolite is cotinine.

Cambridge filter pad
Commercially available glass fibre filter pads which collect the samples of smoke constituents in smoking machines used in tobacco research.

Carbon monoxide (CO)
A colourless and odourless constituent of cigarette smoke, formed during incomplete combustion of organic substances. CO is a HPHC.

CEN (European Committee for Standardisation)
An association that brings together the National Standardisation Bodies of 34 European countries. CEN provides a platform for the development of European Standards and other technical documents in relation to various kinds of products, materials, services and processes.

Cigarette machine yield
The amount of smoke collected by a smoking machine from a cigarette under a specified smoking regime.

Closed system
Vape devices which use a cartridge and battery element. The main difference between open and closed systems is that, in the latter, the cartridge cannot be refilled by the user. This effectively ensures closed devices are controlled systems which users are unable to alter or adulterate.

Combustibles
The collective term used to refer to a range of combustible tobacco products. In addition to cigarettes, also includes products like cigars or pipe tobacco.

Compensation
The change in consumers’ smoking behaviour that may occur in response to using a different product. i.e. taking longer, deeper breaths.

COPD (Chronic Obstructive Pulmonary Disease)
An umbrella term covering several lung conditions, including emphysema and chronic bronchitis. Characterised by increased breathlessness.

CORESTA
Or ‘Centre de Coopération pour les Recherches Scientifiques Relatives au Tabac’ (Cooperation Centre for Scientific Research Relative to Tobacco). CORESTA is an association whose purpose is to promote international cooperation and best practice in scientific research relative to tobacco and vape products.

CORESTA Recommended Methods (CRMs)
Standardised analytical methods as developed by the CORESTA organisation.

Cotinine
A metabolite of nicotine, sometimes used as a biomarker of exposure for products containing nicotine.

Cytoxic/Cytotoxicity
The ability of a substance to cause cell death or halt cell replication and growth. This suggests it’s toxic.

Dependence
Where a product (e.g. coffee) is enjoyed regularly with minimal prospect of harm but can be difficult to reduce usage or quit entirely.

Dose
The amount of a substance received by a biological system (e.g. the body) during exposure.

Dose response
The associated biological response related to the dose of a substance over time. Typically, the larger the dose, the greater the effect.

DPM (Dry particulate matter)
Particulate matter is sum of all solid and liquid particles suspended in air. Total particulate matter is produced after the deduction of water content. For cigarettes, this is expressed as milligrams per cigarette.

E-cigarette
A term used by some public health bodies to refer to e-vapour products. However, we prefer to use the terms ’vape’ and ‘vaping’.

E-liquid
The liquid used by vape products to generate aerosols for inhalation. May contain nicotine, carriers such as propylene glycol or glycerol, and/or additives (e.g. flavours).

Emissions
The smoke or aerosol produced when a cigarette or NGP is used. Emissions may refer to the total aerosol, or individual components within it.

ENDs and ENNDs
Electronic Nicotine Delivery Systems and Electronic Non-Nicotine Delivery Systems are terms used to refer to vape products by some public health bodies, including the WHO.

Epidemiology
Epidemiology is the study of how often diseases occur in different groups of people and why. For example, epidemiologists have identified cigarette smoking as associated with lung cancer.

ETS
Environmental tobacco smoke, or ETS, is the aged and diluted combination of the smoke that rises from the lit end of a cigarette and the smoke exhaled by the smoker.

Electronic Vapour Product (EVP)
A battery powered device which heats an e-liquid to produce and aerosol or vapour. Also known as a vape.

Flavourings
Ingredients commonly used in food may be used in very small amounts to give each product a distinctive flavour characteristic or aroma.

Food and Drug Administration (FDA)
US government body responsible for ensuring the safety, effectiveness, and quality of products – including granting regulatory approval before sale. Within the FDA, the Center for Tobacco Products (CTP) is responsible for regulating the manufacturing, marketing, and distribution of tobacco and tobacco-related products. (See PMTA for the regulatory approval pathway).

Framework Convention on Tobacco Control (FCTC)
An international framework under the World Health Organisation that proposes measures for the control and regulation of tobacco products.

Gene
A specific sequence of DNA that often code for functional molecules called proteins (e.g. an enzyme).

Gene Expression
The process whereby a gene is de-coded by activating then translating it into a functional molecule, or protein. In simple terms, a gene is like the recipe and protein is like the cake instructed by the recipe.

Genome
An organism’s set of genetic instructions. Each genome contains all the information needed to build, grow and develop that organism.

Genotoxic/Genotoxicity
The ability of a substance to cause damage to DNA resulting in mutations and which may lead to cancer. Toxic to the genome. Genotoxicity is different to mutagenicity; all mutagens are genotoxic, but not all genotoxic agents are mutagenic.

Harmful or Potentially Harmful Constituents (HPHCs)
A list published by the FDA of harmful and potential harmful constituents (see HPHCs) found in tobacco smoke.

Habit
Where a product (e.g. chocolate) is enjoyed regularly with minimal prospect of harm.

Heated Tobacco Product (HTP)/Heat-not-burn
Devices that use a heating element to generate an aerosol from tobacco without burning it.

Humectants
Ingredients added to regulate the moisture content of our tobacco and tobacco-free products. 

In-vitro
Studies on cells or biological molecules outside of their normal biological context. i.e. in the laboratory.

In-vivo
Biological studies conducted in a living organisms. i.e. humans, animals and plants.

ISO
Or International Organisation for Standardisation . The world’s largest non-governmental system for voluntary industrial and technical collaboration at the international level, coordinating the exchange of information around international and national standards.

ISO Smoking Regime
An internationally validated machine-based method for generating cigarette smoke under controlled conditions (e.g. defined airflow, ambient temperature and humidity). ISO puffing conditions are a 35cm³ puff volume, a 2 second puff duration and a puff frequency of once per minute – with smoking continuing to a fixed length from the tipping paper or filter.

ISO 17025
ISO/IEC 17025:2005 is a standard which specifies the general requirements for the competence to carry out tests and/or calibrations, including sampling. It covers testing and calibration performed using standard methods, non-standard methods, and laboratory-developed methods. Laboratory customers, regulatory authorities and accreditation bodies may also use it in confirming or recognising the competence of laboratories.

IVM Validated Assay
In-vitro micronucleus (IVM) test is used to toxicologically screen for potentially genotoxic (see Genotoxic) compounds.

Mainstream Smoke
Smoke which is inhaled from a cigarette during smoking. Doesn’t include sidestream smoke.

Metabolite
A biological breakdown product of a substance. e.g. nicotine is broken down into cotinine, so cotinine is a metabolite of nicotine.

Method Validation
The gold standard of analytical practice. Method validation is the approach used to confirm that analytical procedures employed for specific tests are robust, repeatable and reproducible.

Mutagen/Mutagenic
A mutagen refers to a physical biological or chemical agent that causes an increase in DNA changes (mutations) above a normal level. Mutagens may harm cells and may cause certain diseases such as cancer. Examples include X-rays and UV light.

NFDPM (Nicotine-Free Dry Particulate Matter)
Dry particulate matter after deduction of its nicotine content. For cigarettes, it’s expressed as milligrams per cigarette.

NGP (Next Generation Product)
A portfolio of products which decouple nicotine from tobacco combustion and offer adult smokers potentially reduced harm alternatives to smoking cigarettes. 

Nicotine
A naturally occurring chemical found in the tobacco plant and other members of the nightshade family, including potatoes, tomatoes and aubergines.

NRC (National Research Council)
An American non-profit, non-governmental organisation who produce technical reports that aim to shape policies, inform public opinion, and advance the pursuit of science, engineering, and medicine in the USA. (See TT21C.)

Nicotine Replacement Therapies (NRTs)
A range of products, usually licensed medicines. They deliver a low dose of nicotine to users in the form of chewing gums, skin patches, inhalers, tablets or oral sprays with the intention of helping smokers quit.

Neutral Red Validated Assay (NRU)
An in-vitro assay commonly used to assess cell viability (cell death) in response to exposure to a substance.

Oral Nicotine Delivery (OND)
A range of oral products. Includes traditional Swedish-style snus which is tobacco-based, as well as Next Generation tobacco-free products, including zoneX.

Open system 
Vaping devices which use manually refillable e-liquid tanks instead of closed pods or cartridges. Open systems can be refilled by users and potentially adulterated.

Particulate Phase
The fine, solid particles in an aerosol. Often collected on a Cambridge Filter Pad during smoke analysis.

PMTA (Pre-Market Tobacco Application)
Marketing order that must be approved by the FDA before any new tobacco product is launched on the US market. This regulation has now expanded to cover vape products.

Public Health England (PHE)
An executive agency of the UK Government’s Department of Health and Social Care. PHE’s aim is to protect and improve the nation’s health and wellbeing and reduce health inequalities.

Royal College of Physicians (RCP)
A leading British professional body for both UK and international physicians, dedicated to improving patient care and reducing illness.

Reconstituted Tobacco
Also known as ‘Recon’. Created from processed cut or ground tobacco.

Retention
The action of the body holding on to something for example the amount of aerosol or specific constituents. e.g. nicotine retained in the body after smoking/vaping.

Sidestream Smoke
Smoke emitted from a burning cigarette. This does not include mainstream smoke, or smoke exhaled by the user.

Smokeless Tobacco Products
Non-combustible tobacco products, for example ONDs like snus and HTPs.

Smoke Constituent
An individual chemical present in cigarette smoke.

Smoking/ Vaping Regime
Internationally validated parameters under which a product is used (e.g. puff volume, puff duration and puff frequency).

Snus/Swedish snus
Snus is a moist oral tobacco product which is placed behind the lip either loose or in portioned sachets which resemble miniature tea bags. Air-cured tobacco is ground, mixed with water and salt, and then produced using a unique technique called heat-sweating, closely related to pasteurisation.

Tar
A mixture of many different constituents, more correctly known as NFDPM (Nicotine-Free, Dry Particulate Matter). Tar is the TPM (total particulate matter) after deduction of its nicotine and water content, expressed as milligrams per cigarette.

Tobacco Harm Reduction (THR)
A public health strategy aiming to reduce the damage to the health of adult smokers who are uninteresting or unwilling to stop consuming nicotine through traditional methods (primarily cigarette smoking) by encouraging their substitution with other nicotine containing products that potentially pose fewer health risks.

Tobacco control strategies
A comprehensive body of public policy intended endorsed and advocated by various public health bodies to reduce tobacco use.

Total Particular Matter (TPM)
See Tar.

Toxicant
A toxic (poisonous/harmful) substance introduced into an environment (e.g. human body).

Tobacco Specific Nitrosamines (TSNAs)
Tobacco Specific Nitrosamines are chemical compounds found in tobacco and tobacco smoke. The IARC (International Agency for Research on Cancer) has identified 8 tobacco-specific nitrosamines in tobacco and tobacco smoke. Two of them have been classified as Group 1 carcinogens, which means they cause cancer in people.

TT21C
A modern method of in-vitro testing established by the National Academy of Sciences, Engineering and Medicine and the US Research Council. TT21C champions the utilisation of human cell lines in in-vitro research over traditional in-vivo toxicological testing using living animals. Since human cells are prioritised in TT21C, no animal testing is conducted in the research process.

Vape/Vapes
Common term used to refer to e-vapour, EVP or ENDs products.

Vaping/Vaper
Common terms for users/the act of using a vape product.

Vapour phase
The portion of smoke or aerosol which passes through a Cambridge Filter Pad when a product is tested on a smoking machine. E.g. carbon monoxide.

WHO (World Health Organisation)
A specialised agency within the United Nations, focused on the promotion and protection of global public health.