Safety Glossary
Plain-English definitions for health and safety terms you'll encounter across ProductSafer. Understanding these concepts helps you make more informed decisions about the products you use.
A
ADI (Acceptable Daily Intake)
The ADI is an estimate of the amount of a substance — typically a food additive or pesticide residue — that a person can consume every day over a lifetime without appreciable health risk. It is set by regulatory bodies such as EFSA and expressed in milligrams per kilogram of body weight per day. Exceeding the ADI on an occasional basis is unlikely to cause harm, but chronic over-exposure is a concern regulators take seriously.
B
Bioaccumulation
Bioaccumulation is the gradual build-up of a chemical inside a living organism at a rate faster than it can be broken down or excreted. Persistent substances such as PFAS, heavy metals, and certain pesticides accumulate in fatty tissues over time. Animals higher up the food chain tend to carry greater concentrations — a process called biomagnification — meaning predators (including humans) can be exposed to much higher levels than the original environmental concentration would suggest.
BPA (Bisphenol A)
BPA is an industrial chemical used since the 1960s to harden polycarbonate plastics and make epoxy resins that line food and drink cans. It can leach into food and beverages, especially when containers are heated. BPA is a well-documented endocrine disruptor and has been linked to hormonal disruption, reproductive issues, and developmental problems in children. It has been banned or restricted in food-contact materials in many countries, though replacement chemicals are under scrutiny.
BPS (Bisphenol S)
BPS is a chemical increasingly used as a substitute for BPA in products marketed as "BPA-free." It has a very similar molecular structure to BPA and emerging research suggests it may carry comparable endocrine-disrupting properties. Thermal paper receipts are a common source of BPS exposure. Regulatory review of BPS is ongoing, and some scientists caution that swapping one bisphenol for another may not represent a genuine safety improvement.
C
Carcinogen
A carcinogen is any substance, organism, or agent capable of causing cancer by damaging DNA or disrupting normal cellular processes. Carcinogens are classified by organisations such as IARC into groups reflecting the strength of evidence linking them to cancer in humans or animals. Common examples include tobacco smoke, asbestos, certain pesticides, and some processed meat products. Exposure does not guarantee that cancer will develop — risk depends on the dose, duration of exposure, and individual susceptibility.
E
EDC (Endocrine-Disrupting Chemical)
An EDC is a chemical — natural or synthetic — that interferes with the body's hormonal (endocrine) system. EDCs can mimic, block, or alter the production and activity of hormones such as oestrogen, testosterone, and thyroid hormones. Even tiny doses can have measurable biological effects, particularly during critical windows of development such as pregnancy and early childhood. Common EDCs include BPA, phthalates, certain pesticides, and PFAS.
EFSA
The European Food Safety Authority is the EU agency responsible for providing independent scientific advice on risks associated with the food chain. EFSA evaluates food additives, contaminants, pesticide residues, and novel foods, and sets safety thresholds such as Acceptable Daily Intakes and Tolerable Daily Intakes. Its opinions inform EU regulations but it does not have the power to ban substances directly — that authority rests with the European Commission and member states.
Endocrine Disruptor
An endocrine disruptor is any chemical that interferes with the body's hormone-signalling system, potentially causing adverse health effects in humans or wildlife. Unlike most toxins, endocrine disruptors often do not follow a straightforward dose-response relationship — very low doses can sometimes produce significant effects, particularly during sensitive developmental periods. Health outcomes linked to endocrine disruption include reproductive disorders, thyroid dysfunction, developmental delays, and increased cancer risk.
EWG
The Environmental Working Group is a US-based non-profit environmental health research organisation. EWG publishes consumer-facing databases — including the Skin Deep cosmetics database and the Dirty Dozen pesticide list — that rate products and ingredients based on available safety data. Its ratings are widely cited in health journalism, though some scientists note that EWG applies a precautionary approach that may rate risks more severely than official regulatory assessments.
G
GRAS (Generally Recognized As Safe)
GRAS is a US FDA designation that allows food ingredients to be added to products without pre-market approval if they are widely recognised by qualified experts as safe under the conditions of intended use. The GRAS pathway has attracted criticism because manufacturers can self-certify ingredients without formal FDA review, a process sometimes called "GRAS notification" rather than full approval. Thousands of ingredients currently in the food supply have been granted GRAS status through this voluntary route.
I
IARC Classification (Group 1, 2A, 2B, 3)
The International Agency for Research on Cancer classifies substances according to the strength of evidence that they cause cancer in humans. Group 1 ("carcinogenic to humans") includes proven carcinogens such as tobacco and asbestos. Group 2A ("probably carcinogenic") means evidence is strong but not conclusive — examples include red meat and glyphosate. Group 2B ("possibly carcinogenic") covers agents where evidence is limited, such as aloe vera extract and talc. Group 3 means the evidence is inadequate to classify the substance one way or another. IARC classifications reflect hazard, not the level of risk from typical exposure.
M
Microplastics
Microplastics are tiny plastic particles less than 5 millimetres in size, produced either by the breakdown of larger plastic items or manufactured at small sizes for use in products like cosmetics. They are now found virtually everywhere — in oceans, drinking water, air, and even human blood and tissue. Research into their long-term health effects is ongoing, with concerns focused on the plastics themselves and the chemical additives they carry, including plasticisers and flame retardants.
N
Neurotoxin
A neurotoxin is a substance that is poisonous or destructive to nerve tissue. Neurotoxins can disrupt the development and function of the brain and nervous system, with children and developing foetuses being especially vulnerable. Common environmental neurotoxins include lead, mercury, and certain pesticides such as organophosphates. Effects can range from subtle changes in cognition and behaviour to severe neurological damage, depending on the level and timing of exposure.
Nitrosamines
Nitrosamines are a family of chemical compounds that can form when nitrites (used as preservatives in cured and processed meats) react with amino acids under high heat or in the acidic environment of the stomach. Many nitrosamines are potent carcinogens, particularly for colorectal, stomach, and oesophageal cancers. They can also form in some medications and personal care products. Regulatory agencies set strict limits on nitrosamine levels and manufacturers are increasingly required to test for them.
NOVA Group (1, 2, 3, 4)
NOVA is a food classification system developed by researchers at the University of São Paulo that groups foods by the extent and purpose of their industrial processing. Group 1 covers unprocessed or minimally processed foods (fresh fruit, vegetables, meat, eggs). Group 2 includes culinary ingredients (oils, flour, sugar, salt). Group 3 covers processed foods made from Group 1 and 2 combinations (canned vegetables, cured meats, cheese). Group 4 — ultra-processed foods (UPF) — contains industrial formulations with five or more ingredients, often including additives like emulsifiers, colourings, and artificial flavours; this group is most associated with adverse health outcomes in epidemiological research.
Nutri-Score (A–E)
Nutri-Score is a five-colour front-of-pack nutrition label developed in France and adopted by several European countries. It assigns a letter and colour from A (dark green, healthiest) to E (red, least healthy) based on a scoring algorithm that weighs nutrients to limit — such as saturated fat, sugar, and salt — against beneficial nutrients and food components like fibre, protein, fruit, and vegetable content. It is intended to help consumers make quick comparisons between similar products, though critics note it does not account for processing level or portion size.
O
Obesogen
Obesogens are chemicals that can disrupt the body's metabolism and fat-storage systems in ways that promote weight gain, independent of diet and exercise. They may act by interfering with hormone signalling, altering the number or size of fat cells, changing appetite regulation, or disrupting energy balance. Examples under research include tributyltin (found in some antifouling paints), certain phthalates, and BPA. The field is emerging and not all mechanisms are fully understood, but the concept suggests that chemical exposure may be a factor in the global obesity trend.
P
Parabens
Parabens are a group of synthetic preservatives widely used in cosmetics, pharmaceuticals, and some food products to prevent the growth of bacteria and mould. Common types include methylparaben, ethylparaben, propylparaben, and butylparaben. They have weak oestrogenic activity — meaning they can mimic oestrogen in the body — which has raised concerns about their potential role as endocrine disruptors. While regulatory bodies generally consider approved concentrations safe, some health-conscious consumers and brands choose paraben-free alternatives.
PFAS (Per- and polyfluoroalkyl substances)
PFAS are a large family of thousands of man-made chemicals that have been used since the 1940s in products ranging from non-stick cookware and food packaging to waterproof clothing and firefighting foam. The strong carbon-fluorine bond that makes them so durable also means they do not break down in the environment or the human body — earning them the nickname "forever chemicals." Exposure has been linked to thyroid disruption, immune system suppression, certain cancers, and developmental issues in children.
Phthalates
Phthalates are a group of chemical plasticisers added to PVC plastic to make it flexible and durable. They are also found in fragrances, personal care products, food packaging, and medical devices. Phthalates are endocrine disruptors that can interfere with testosterone and other hormones, and are associated with reproductive abnormalities, developmental problems in children, and metabolic disorders. Several phthalates have been restricted or banned in toys and childcare articles in the EU and US, though many remain in widespread use.
This glossary is for informational purposes only and does not constitute medical advice.