What is in cigarette smoke

Cigarette smoke contains more than 7,000 chemical compounds; at least 69 of them are classified as carcinogenic. The list below is not all of them — it is the ones whose names bring a place to mind.

• AcetoneThe main ingredient in nail polish remover.
• AmmoniaThe sharp-smelling stuff in glass cleaner.
• ArsenicOnce the classic ingredient in rat poison.
• CadmiumThe metal inside nickel-cadmium batteries.
• Polonium-210A radioactive element. Yes, it's in the smoke.
• FormaldehydeThe preserving fluid in anatomy labs.
• Carbon monoxideThe colourless, odourless gas from exhaust pipes.
• Hydrogen cyanideA gas once used as a pesticide.
• BenzeneThat smell at the petrol station.
• ButaneThe gas inside your lighter.
• TolueneThe solvent in paint thinner and some glues.
• LeadThe heavy metal banned from old paint.
• NaphthaleneThe smell of mothballs in the wardrobe.
• Benzo[a]pyreneThe compound in smoke from charred meat.
• NicotineIt was once sold as an agricultural pesticide.
• TarNot one substance — the total of everything in the smoke.
• AcetaldehydeThe compound behind the hangover headache.
• AcroleinThe choking smoke when oil burns in the pan.
• MethanolThe alcohol used as racing fuel.
• Tobacco-specific nitrosaminesA family of compounds found only in tobacco.
• Chromium (VI)The plating compound from metal workshops.
• NickelThe metal that gives cheap jewellery its allergy.
• 1,3-ButadieneThe raw material of synthetic rubber.
• Vinyl chlorideThe gas that PVC pipes are made from.
• StyreneThe raw material of styrofoam.
• PhenolThe ancestor of hospital disinfectants.
• HydroquinoneThe lightening agent in skin-spot creams.
• PyridineMuch of what you call 'the smell of smoke'.
• Ethylene oxideThe gas that sterilises surgical instruments.
• 4-AminobiphenylOne of the first substances banned from dye works.
• CobaltThe metal in your phone battery.
• CrotonaldehydeThe compound that slows your immune cells.
• CatecholThe darkening agent in hair dye.
• FuranA compound food agencies watch for in canned goods.
• QuinolineA compound extracted from coal tar.
• MercuryThe silver liquid in old thermometers.
• IsopreneThe building block of natural rubber.
• BerylliumThe specialty metal of aerospace and nuclear work.
• Nitric oxideThe gas that relaxes vessels, then wears them out.
• Urethane (ethyl carbamate)A compound monitored in fermented drinks.
• AcrylamideWhat forms in the browned part of a chip.
• AcrylonitrileThe raw material of acrylic sweaters.
• AcetamideUsed industrially to soften plastic.
• Aflatoxin B1The toxin in mouldy nuts.
• 2-NaphthylamineRemoved from industry because of bladder cancer.
• 1-NaphthylamineIts twin was banned; this one stayed.
• AnabasineNicotine's lesser-known sibling.
• NornicotineThe intermediate nicotine turns into.
• Today's chemicalo-AnisidineAn intermediate in fabric dyes.
• CoumarinThe hay-and-vanilla note in tonka bean — banned as a food additive.
• Caffeic acidIt's in coffee too — but dose is the issue.
• CresolsThat sharp smell of coal-tar soap.
• Chlorinated dioxins and furansThe reason incinerators are so tightly monitored.
• 2,6-DimethylanilineA relative of the dentist's anaesthetic.
• ChryseneThe ringed compound in asphalt fumes.
• Benz[a]anthraceneIn the smoke when fat drips onto the coals.
• Benzo[b]fluorantheneA tracer of diesel exhaust in city air.
• Benzo[k]fluorantheneA PAH that glows under ultraviolet light.
• BenzofuranA compound obtained from coal tar.
• NNKA carcinogen found only in tobacco.
• NNNWhat nornicotine turns into during curing.
• NDMAThe compound behind recent drug recalls.
• NDEAUsed in labs as a liver-damage model.
• NDELAA contaminant banned from cosmetics.
• NMEAFrom the nitrosamine family watched in cured meat.
• NMORMeasured in the air of rubber factories.
• NPIPBorn from a ring also found in black pepper.
• NPYRThe compound looked for in fried bacon.
• NSARA nitrosamine that can also form inside the body.
• NitrobenzeneSmells of almonds but is not almond.
• NitromethaneThe fuel of drag racing engines.
• 2-NitropropaneThe solvent in printing ink.
• HydrazineThe fuel of satellite thrusters.
• Methyl ethyl ketoneThe smell of contact adhesive.
• PropionaldehydeAn intermediate for plastics and fragrance.
• Propylene oxideUsed to sterilise spices.
• Vinyl acetateThe raw material of wood glue.
• EthylbenzenePart of what petrol smells like.
• SeleniumA deficiency in small doses, a poison in large ones.
• Uranium-238Radioactive but slow: a 4.5-billion-year half-life.
• Uranium-235The fuel isotope of nuclear power plants.
• Indeno[1,2,3-cd]pyreneA PAH named in air quality reports.
• Dibenz[a,h]anthraceneMore active than its famous cousin benzo[a]pyrene.
• Dibenzo[a,l]pyreneAmong the most potent PAH carcinogens measured.
• Dibenzo[a,e]pyreneThe quieter member of the same family.
• Cyclopenta[c,d]pyreneThe signature of car exhaust.
• Benzo[c]phenanthreneIts curved shape grips DNA differently.
• Benz[j]aceanthryleneA compound met only in combustion research.
• 5-MethylchryseneOne methyl group changes everything.
• PhIPThe most abundant compound on seared meat.
• IQA chemical by-product of the searing smell.
• Trp-P-1Born from a burning amino acid.
• Glu-P-1Forms when the source of umami burns.
• A-α-CThe ring that appears when protein burns.
• DiacetylThe compound that gives popcorn its butter taste.
• Acetyl propionylDiacetyl's replacement — with the same concern.
• Propylene glycolThe carrier in stage fog — and in vape liquid.
• GlycerolThe sweet syrup in soap and cake.
• GlycidolThe compound that appears alongside heated fats.

Source: The substances come from three sources: the U.S. Food and Drug Administration's list of harmful and potentially harmful constituents in tobacco products, and reports from the World Health Organization and the U.S. Surgeon General. Carcinogen classifications come from the International Agency for Research on Cancer (IARC). Each card names its own source underneath.