On coverage of the Ohio train derailment remembers the issue isn’t scary chemical names it’s what the chemical compounds are and their concentrations in the environment that are an issue. Anyone who tells you a big black cloud of chemical smoke is good to breath or ok to breath is obviously lying. At the same time don’t be scared by merely referring to normal substances by their chemical names.  The mainstream media is rightly not overblowing this disaster.  It is bad.  You wouldn't want to consume the released substances.  At the same time, it is not anything like Chernobyl. 
Take for example this well-known streamer Jeremy Hambly aka "The Quartering" who usually follows anti-woke trends of all kinds seems to find one issue on which he will act "woke", chemophobia.  The one phobia the woke left are ok with unless those chemicals are hormones and hormone blockers (which when used at the right times for the right people are totally safe but then some folks ignore the scientific guidelines.)

I am not a chemist, but I do know chemistry. When vinyl chloride is burned it releases hydrogen chlorite and carbon monoxide for the most part. These are both toxic but far less toxic than the vinyl chloride which is why they burned it off. Burning is just a chemical reaction and it does not necessarily result in a more dangerous substance than the substance being burned. Even as scary as it looks. That is not to say you should go breathing in any such chemicals.  This situation is bad for the local area but it's not anything like a Chernobyl or a coverup.  There would have to be something far worse than vinyl chloride in the train for that to be the case. 

UPDATE and NOTE: VinylChloride is indeed a dangerous compound more dangerous than the hydrogen chloride.  That's why it was burned.  The chemical that did not burn but just spilled is going to be an issue. 

Also note it's not the chloride that makes it dangerous or the Vinyl alone it is the specific chemical properties of the compound that make it either dangerous or safe.  The only ways to know are to either trust the scientists who know about this or become one.   Situations like this one call for rational caution not irrational anger or panic.

Now as for the hydrogen chloride. If you have ever seen on your oral medications the abbreviation “HCl” on them that is because every one of those medications has hydrogenchloride in a safe form as part of their makeup. HCl in the presence of water vapor forms Hydrochloric acid. Which would not be good to drink but is non the less inside you right now. Your stomach acid is hydrochloric acid. Because I know people don’t like to believe that it is true and here are some links. In fact, if you have too much or too little of it in your body it can cause problems… everything from heartburn to ulcers and more. Without it you could not digest food though.

What about the dead fish in rivers? This is not really a surprise that creeks near by or in places where the HCl would rain out this would be a problem. Streams and rivers concentrate the run off. Fish are naturally very sensitive to toxins in the water. Water is to fish as air is to us. So the surface water would not be safe for them.  Unless you drink water straight from a stream without treating it it would not be safe for you either. 

Newsweek reports on the full list of chemicals released with Vinyl Chloride being the majority of it.  Again I am not a chemist but if these substances were burned and what they produce upon burning VS being released without burning makes a difference.   Burning might make some substances that are more or less toxic than the unburned chemicals. https://www.newsweek.com/ohio-train-derailment-toxic-chemicals-list-epa-1780805

Vinyl chloride: a colorless gas that is used to make polyvinyl chloride (PVC) plastics and is highly flammable and decomposes to make toxic fumes. According to the National Library of Medicine, it is also carcinogenic and can cause other health issues.
Butyl acrylate: a clear liquid that is used for making paints, sealants and adhesives. It is flammable and can cause skin, eye and respiratory irritation.
According to the NIH the suggested disposal method is incineration with emissions controls.  Given the situation burning was probably the lesser evil. 
Ethylhexyl acrylate: a colorless liquid used to make paints and plastics. It can cause skin and respiratory irritation and, under moderate heat, can produce hazardous vapor.
Similar to the above substances incineration with chemical scrubbers to detoxify the exhaust is the preferred method of disposal.  Of course an open plume of smoke is not good but is better than the unburned compound. 
Ethylene glycol monobutyl: a colorless liquid used as a solvent for paint and inks, as well as some dry cleaning solutions. It is classed as acutely toxic, able to cause serious or permanent injury, and highly flammable. Vapors can irritate the eyes and nose, and ingestion can cause headaches and vomiting.
According to the NIH the suggested method of disposal is atomization by incineration. 

Many of these substances are disposed of by incineration into much less toxic chemicals.   This is not an argument that having a chemical fire on a derailed train is just fine and dandy like sour candy.  This is a bad situation, but the first responders made the right call.  Controlled fire is much better than uncontrolled release of chemicals.  Just remember for now the line between non-toxic, and less toxic is often concentration and application.  This leads to a question for those who live in the area.  

What about the well water?

This is where people in the area should get a test not just from railroad employees but should really be getting the water tested by the state or by a lab they hire. If someone has a private well on their property regular testing of the water is usually a part of the cost of owning such a well so they would have contact with a testing lab. At any rate here is a listing of such laboratories maintained by Ohio state university.

I am no expert on this matter but if I was in the area I would test my well water at least weekly for the next several months.  That may be overkill but ground water tends to move slowly.  Living in a municipality that relied on well water I know changes in the aquifer do not happen on the scale of a week.  

It will also be a good idea to compare past test results to current test results and note any changes.  

Don’t Fear Chemical Names, Educate Yourself.

The key to understanding these situations is some basic facts of nature.

Everything you see, eat, touch, taste and smell is a chemical made of atoms and molecules. Aside from phenomena like light or other electromagnetic forces, everything in the universe you interact with is a chemical. So, saying there are chemicals in the water is like saying there are chemicals in that chemical.

Chemical names are not what makes a given chemical scary. Water is dihydrogen monoxide. Salt is sodium chloride. Sodium chloride mixed with water, salt water, is of no danger at all unless you drink a lot of it and don’t drink fresh water at all. Pure natural sodium is an elemental metal that if mixed with water will explode. Like this

Last but not least, if you live near a rail line plan ahead for the unlikely event of a derailment nearby. Ask your local fire department or other authorities about their plans. Have two weeks of water stored (especially if you rely on your own well). Have two weeks of food stored. Have a means for evacuation if needed. These last steps are good for any type of disaster.

Last but not least it has to be said that events like this derailment should never be minimized. Any regulations or protections that can be put in place to minimize the risk to the general public should be in place. That said there can never not be a risk. We are in a world made of plastic and steel full of substances with scary names that are no dangerous and things, like sodium, or mercury, which have simple names and are VERY dangerous.

Minor Update: To put the current accident in Ohio in context USA today looked into 10 years of data, and CNN reported on it as well.  

So yes this is a bad situation for that local area.  However, calling this a Chernobyl when it is not even a 3 mile island is not correct.  It's bad but not that bad.