The 21 Most Dangerous Chemicals in the World (Steer Away!) (2023)

Chemistryis fascinating, I’m sure we all agree on that. Not only that: thanks tochemistry we know of many compounds that are extremely harmful if not handledproperly. Today we will share with you acomprehensive list of the most dangerous chemicals known to man.

Chemicals are not bad (even not-organic ones). The thing is, everything we see or touch in our world, is made up of chemicals. From the purest distilled water that we use as solvent in the lab to a carrot that you just harvested from your backyard.

But thereare many poisons out there in Nature, and other dangerous chemicals that may ormay not be human-made.

On thisinformative article, we wanted to cover some of these scary compounds which youmight want to steer away from.

If you are not a professional scientist, you probably will not encounter many of them in your every-day life, or for sure in any experiment that you might do at home but still is good, or interesting to be aware of them. or maybe you want to warn your chemist friend (together with a cool gift)

On theother hand, if you are a chemist, it is definitely possible that you might haveto use some of these for your work. And it is always good to be prepared, soyou can take the appropriate safety measurements. Or just nope the hell out ofusing them if ever asked to.

So, what is the most dangerous chemical known to man? What is the most toxic chemical?

What Kind of Dangerous Chemicals Are WeReviewing?

We have decided to divide the compounds in different categories.

This will depend on whether they are dangerous because they are poisonous (low LD50), corrosive, explosive, or extremely harmful chemicals for some reason.

We alsohave a category for typical dangerous laboratory chemicals (definitiely worthchecking out if you’re a chemist or chemistry student).

Finally, we will also discuss some very dangerous compounds that can be found in every-day life situations.

In any case, all these nasty chemicals are interesting to know about.

Withoutfurther ado, let’s look into them!

The Most Dangerous Poisons

Botulinum toxin

Botulinumtoxin, is basically the most lethalpoison known to man. An average 70 kg human being only would have to takearound 100 nanograms of this protein to die (it has an LD₅₀ of1.5–2.0 ng/kg).

If you put it in perspective, one gram of this toxin can kill more than one million people!

Whatthis toxin does chemically is basically preventing acetylcholine from beingreleased between neuron connexions. This breaks down the connexions of neuronswith with muscle cells. This leads to muscle paralysis, as contraction of themuscle cells cannot take place.

Ifyou take enough, the neuron connexions which make the heart or respiratorysystems work go down, which can kill you.

Funnilyenough, this toxin is used in medicine. Botulinum toxin is commercialized underthe name of Botox, among others.

As a tool that can paralyze muscles, it found uses in treating muscle spasticity (muscles that are contracted all the time) or other muscle-related diseases. The most potent toxin in the world has even been used in cosmetics, in order to “smooth” facial muscles!

Batrachotoxin

Following next, the next poison comes off the skin of some dart frogs. Specifically, phyllobates terribilis or Golden Poison Frog is known for being one of the most dangerous poisonous animals in the wild.

Oneof the key components of their poison is batrachotoxin.

Contraryto botulinum toxin, which is a protein, batrachotoxin is a small organicmolecule.

You can see how their structures have absolutely nothing to do with each other. But they both work in a fairly similar manner: batrachotoxin, with an LD₅₀ of 2000 ng/kg (an order of magnitude less poisonous than botulinum toxin, but still scary), is also a neurotoxin. It blocks the Na+ ion channels permanently, preventing neurons from communicating with muscles, leading to paralysis and eventually heart failure.

Interestingly,dart frogs don’t make batrachotoxin by themselves.

Theyneed to ingest certain alkaloids through their diet. If they are kept incaptivity, dart frogs are rendered non-poisonous.

Butin the wild, they make one of the most dangerous poison mixtures. Dart frogscan only be found in Colombia or Panama rain-forests, and they were used byindigenous tribes to make poisonous darts and arrows. That’s where they gettheir name from.

Ricin

We are backto the protein world with ricin.This is yet another order of magnitude less poisonous than botulinum toxin.Ricin’s LD₅₀ is 22.000 ng/kg. But this still means that 2 mg ofricin will kill an average adult.

Oneof the most dangerous chemicals in the world, ricin, can be find in castorbeans.

Themechanism of action of ricin is very different to the one for botulinum toxinor batrachotoxin.

Thisprotein disrupts the ability of the body to assemble proteins from amino acidsin the ribosomes.

Sincethe mechanism of action is much subtler than for other toxins, the symptomstake time to show up. But they eventually do. The inability to make proteins (avery basic type of cell metabolism, essential for cells to survive), causesdamage to the nervous system, kidneys and liver in hours to several days.

Ricingot more popular around the world after its appearance in AMC show Breaking Bad.

Maitotoxin

We are coming back down in the LD₅₀ score, since maitotoxin has a value of 50-130 ng/kg in mice. This is the highest for non-protein compounds. It is produced by a species of dinoflagellates, gambierdiscus toxicus, and can be found on the surface of some algae in Polynesia, or some animals such as the ciguateric fish.

But from achemical point of view, the most interesting feature of maitotoxin is not itstoxicity, but its chemical structure.

Maitotoxinis not a protein, but I wouldn’t call it a small molecule either. With amolecular weight of 3422 g/mol, maitotoxin is one of the toughest unbeatensynthetic challenges out there.

This impressive amphipathic structure made up of 32 fused rings and a handful of stereogenic centers has not been synthesized completely in organic chemistry labs. The research group of K. C. Nicolaou is involved on the total synthesis of this giant. So far, the synthesis of some of the ring domains has been published, but the entire molecule is still a challenge to overcome.

Tetrodotoxin

Tetrodotoxinis another small molecule, which similarly to batrachotoxin, is a potentneurotoxin. It is also a sodium channels blocker.

This poisonis the one that makes dangerous several kinds of animals: fishes such as theporcupine fish or pufferfish. Also, blue-ringed octopuses or moon snailsproduce tetrodotoxin.

This is not a huge molecule as maitotoxin, but it is still an attractive synthetic target that has been the objective of many total synthesis project. The structure of the molecule was elucidated by Woodward in 1964, and the first total synthesis was reported in 1972.

Phosgene: COCl₂

All thepoisons covered above are made by natural sources. However, phosgene, a trulysmall molecule, is human-produced in the range of several tons a year.

Phosgene,or carbonyl chloride, is classified as a chemical weapon, and it is responsiblefor many thousands of deaths during World Wars. A median concentration in air(LC₅₀) of 200-500 parts per milion is enough to kill a person.

Despitebeing one of the most dangerous chemicals in history, it is an extremely usefulreactive building block on chemical synthesis, and it is massively produced andused all over the world.

It is normally made by reaction carbon monoxide with chlorine gas, and it is employed in the synthesis of carbonates, isocyanates (precursors of polyurethanes), among others.

The Most Dangerous Acids and Bases

Hydrogen fluoride: HF

Hydrogenfluoride is not a very acidic acid. In fact, it’s the least acidic of all thehydrogen halides.

But it isactually the most dangerous.

HF isextremely toxic and corrosive. As it happens with many fluorine-containingcompounds, it has weird properties.

Fluoridereally loves binding to silicon, so HF can easily eat through glass (made ofSiO₂). This is the reason it needs to be handled and stored inplastic containers.

But HF canalso bypass our skin barriers, and go through reaching the bones, dissolvingthem as CaF₂ is formed.

The guys atPeriodic Videos have performed some experiments showing how scary this acid canbe:

As you cansee, there is a difference between an acid being “strong” and being“corrosive”.

Fluoroantimonic acid: HSbF₆

Fluoroantimonic acid is one of the most acidic compounds known to man. It is what is called a “superacid”. These are usually defined as chemicals which have an acidity (or ability to donate protons, H⁺) larger than pure sulfuric acid.

It isactually made by mixing HF with SbF₅. Surprisingly, this combinationbetween a relatively weak Brønsted acid (HF) and a Lewis acid (SbF₅)gives rise to a compound which is 20.000.000.000.000.000.000 (2·10¹⁹)times stronger than H₂SO₄.

Piranha solution

Piranha solution is the name that chemists give to a mixture of hydrogen peroxide and sulfuric acid. H₂SO₄ and H₂O₂ react giving H₂SO₅ (Caro’s acid) and water.

Thisresults on a strongly oxidizing acidic mixture. The “piranha” name is quiteappropriate, since it easily eats through organic matter.

As a matterof fact, this mixture is used by chemists to remove organic residues fromglassware (although the glassware has to be very valuable and all other commonmethods unsuccessful).

tert-Butyl lithium: t-BuLi

One of themost common dangerous laboratory chemicals is tert-butyl lithium. We have switched it to this category because itis an extremely strong base.

This makes it very useful in organic chemistry. If a proton cannot be abstracted by t-BuLi in an organic molecule, you will most likely not be able to remove it with anything else.

It can even react with THF (a common organic solvent, which usually are very chemically innert) at room temperature, removing one of their protons and leading to decomposition.

t-BuLi is very pyrophoric, itreadily reacts with air catching fire, that’s why it has to be handled andstored with very special care, always under a protective inert atmosphere ofpure nitrogen or argon.

The Most Dangerous Laboratory Chemicals

Dimethyl mercury: HgMe₂

KarenWetterhahn was a chemistry professor working on toxic metal exposures.Ironically, she died in 1997, due to exposure to dimethyl mercury.

One of themost famous dangerous lab chemicals is Me₂Hg. Prof. Wetterhahn wasusing full protective equipment, but unfortunately, a couple of drops ofdimethyl mercury fell in the top of her gloves. The amount of compound thatcould be absorbed through the gloves and her skin was enough to kill her bymetal poisoning, slowly, after less than a year. Even using very strongchelation therapy, it was not possible to save her life.

Dimethylmercury was used in very specialized NMR experiments using ¹⁹⁹Hgnucleus, but I don’t think I would ever work with it. Me₂Hg canactually go through most types of safety gloves. The use of this substance inany scenario is strongly discouraged.

The priceof a potential accident is just too high.

Dimethyl cadmium: CdMe₂

If youthought dimethyl mercury is nasty, meet its bigger brother, dimethyl cadmium.It is not only highly toxic as Me₂Hg, but it is also highlyreactive.

Dimethylmercury reacts with air, or organic matter, not only exploding but also givingrise to more and more toxic Cd-compounds.

Dimethylcadmium is also very volatile, and inhaling only a few micrograms of it canlead to cadmium metal poisoning, and eventually, to death.

Diazomethane: CH₂N₂

Diazomethane is the simplest diazo compound there is.

Diazocompounds are organic molecules which have a -N₂ functional groupattached to it. As you can imagine, thermodynamically, that nitrogen reallywants to jump out of the organic molecule and leave as nitrogen gas.

So these compounds are extremely reactive, and some of them have a high tendency to explode. Besides, they are usually extremely toxic. Specifically, several deaths have been reported by diazomethane poisoning.

It is auseful reagent in organic chemistry, since nitrogen gas release is an extremelypowerful driving force for achieving difficult chemical transformations, suchas cyclopropanation or homologation reactions. Finding alternatives todiazomethane and its derivatives is an important challenge in modern organicchemistry.

Chloride trifluoride: ClF₃

Chloridetrifluoride is a compound which will look very unusual to you if you don’t havea very advanced chemistry knowledge. This is a hypervalent chlorine compound,with three fluorides attached to it.

ClF₃ is a very poisonous and reactive gas, which has found applications in fieldssuch as rocket fuel research (although it is not used yet as rocketpropellant), or as fuel in nuclear reactors.

Itis manufactured by mixing F₂ and Cl₂ gases and thenseparating it by distillation.

Itis a highly oxidizing agent. It can also act as a potent fluorinating compound.

Dioxygen difluoride: FOOF

As far asoxidants go, dioxygen difluoride is the top pick.

It can beprepared by mixing oxygen and fluorine gas, and the resulting compound is sooxidizing and unstable, that it starts decomposing even at temperatures as lowas -160 ºC. It hass a funny structure, common to the one for classicalperoxydes

O₂F₂ reacts in a vigorous manner with virtually any chemical that it comes incontact with. It is usually referred to by the name “FOOF” due to its hightendency to make anything explode.

Osmium tetroxide: OsO₄

Osmiumtetroxide is not as scary as the last previous oxidants, but it is also a muchmore common laboratory chemical.

Thisreagent is great for oxidizing alkenes to diols, or for epoxydation reactions.As a matter of fact, most of the chemistry awarded one half of the 2001 Nobelprize in chemistry (to Barry Sharpless) is based on the use of osmium oxidesfor the asymmetric oxidation of alkenes.

However,one should handle this chemical with care. OsO₄ is very poisonousand inhalation of small concentrations can cause pulmonary edema, and cases ofdeath have been reported.

Handlingosmium tetroxide with care, and disposing it appropriately is of greatimportance.

Fluorine: F₂

Playingwith fluorine gas is something most chemists are scared of.

However,due to its very particular properties, introducing fluorine atoms intomolecules is of great interest in organic synthesis and all its applications.

That’s whythere are many research groups specialized in doing fluorine chemistry.

But a greatdeal of care must be taken. The following video illustrates how fluorine can behave.

Fluorinereacts with moisture to give hydrogen fluoride, which is scary enough byitself. But contrary to HF that can be handled in solution, F₂ hasto be handled as a gas, and always using containers and tubing made ofresistant plastic materials.

The Most Dangerous Chemicals in “Real Life”

Carbon monoxide: CO

Carbonmonoxide can be a silent killer.

It can bindto the iron atom in hemoglobin, displacing oxygen, basically shutting down cellrespiration.

Carbonmonoxide, along with CO₂, is one of the products of burning organicmatter. If the concentration of oxygen is low during combustion, the amount ofCO that is produced increases. This can happen in a closed fireplace inside ahouse, and you could get poisoned without noticing.

In fact,dozens of deaths are reported every year due to CO poisoning.

Amatoxin

We are backto natural poisons, this time discussing amatoxin.

This is ageneral name for several toxins with a similar structure (several amino acidsarranged in a macrocyclic fashion) that are responsible for the toxicity ofdifferent mushrooms, such as the death cap (amanitaphalloides).

Thereis nothing as picking up your own shrooms out in the goods and making a greatmeal out of it… But it can also be dangerous!

Alwaysmake sure you known perfectly well what you are getting your hands into, and ifyou are in doubt, ask an expert before eating any mushrooms.

The Most Dangerous Chemicals… For Other Reasons

Azidoazide azide

Thiscompound with a very illustrative name (and structure), is one of the mostexplosive chemicals that has ever been prepared.

Azidoazideazide is among the “high-nitrogen energetic materials”, and its molecularformula of C₂N₁₄ speaks for itself.

Thethermodynamic feasibility of this substance to react releasing nitrogen is justHUGE.

Anythingcan set if off. Hit it with something, it explodes. Heat it up, it explodes.

Idon’t recommend any of you ever getting close to this stuff. Instead, justcheck out what other people have already tested:

Thioacetone

Smell mayseem like a “minor” danger sign for a chemical. But it can get beyondunpleasant, to the realm of actually being literally unbearable.

One of themost extremely unpleasant odors in chemistry comes from thioacetone.

Imagine anacetone molecule in which you swap the oxygen for a sulfur atom. The result isa substance with one of the worst smells known to man.

A famousincident involving this molecule involved a couple of milliliters dropped in aGerman laboratory in 1889.

The resultwas people unconscious and vomiting in a radius of almost one kilometer (half amile).

For its extremelyfoul odor, thioacetone is considered one of the most dangerous chemicals in theworld.

We are now wrapping up this list of really dangerous chemicals. These guys are the actual chemicals that should scare you, but do know that everything out there is made of chemicals, which simply can be very good or very bad!

Make sure to share if you found this useful or interesting, and up next, check out our explanations for 100 chemistry facts!