That's literally true, but not the intended meaning. Chemical has become a synonym for "man-made". It's a useful distinction. If you were forced to choose between eating 100g of a random "chemical" molecule, or 100g of a random "natural" molecule, you would be much better off with the latter.

True, scientific studies can show that chemical X is harmless, but.... only if the study was done over a very long time. Only if it was done properly. Only if the scientists didn't receive their financing from BigCo.

It's perfectly reasonable to be wary of "chemicals", heuristically.

EDIT: To be clear, I'm not one of these people living in mistrust of chemicals. But I understand where they're coming from, especially if they have a poor grasp of science. A reasonable move for Kasparov (e.g.: sacrificing his queen for tactical advantage) might be a terrible move for me in the same situation.

Here, have a delicious puffer fish. I prepared it myself!

Rating chemicals by whether or not they occur naturally is a really piss-poor way of judging danger. There is a practically unlimited number of naturally occurring chemicals what will knock you dead, and there are similarly tones of synthesized chemicals that are completely harmless, or even beneficial. Bringing "synthesized vs. naturally" is always disingenuous, we have had better ways of judging danger since the dark ages.

we have had better ways of judging danger since the dark ages.

That's true. And if you trust scientists and the FDA to do their jobs, you're all set. But what if you don't? Let's say that I'm at the supermarket in a small, poor country with a corrupt FDA, and I want to buy some juice. Well, I'm going to favor those brands with natural ingredients (and hope that the ingredient list is correct). Maybe that's a stupid move, but it has served me well so far.

Apologies, I sometimes forget some people find that word particularly offensive.

^ and they even messed this up on occasion: http://en.wikipedia.org/wiki/Tomato#History

As for tomatoes, there was a serious lack of information regarding many topics in Europe at that time. Did the people living in lands to which the tomato is indigenous suffer from that misperception?

Anyway, the point is to analyze these substances based on what we know now, not what someone thought 250 years ago.

That is a distinctly ignorant and biased statement. Go eat 100g of sand, of seawater, tree bark, crude oil, or algae. Notice how I stacked the deck in that list, as these are just naturally occurring things not merely chemicals. Try eating 100g of caffeine, botulinum toxin, vitamin E, nicotine, DNA, warfarin, morphine, or ricin.

Nature is far from harmless, it's merely familiar so that we are more prone to accept whatever degree of harm it holds as, well, "natural". Man-made novel chemical compounds are not all harmless either, but imagining that there is a firm barrier between "natural" and "man-made" and that one category is far and away safer than the other is superstitious thinking.

The other part is the assumption that "natural" molcules are inherently better. There is no difference between naturally-occuring vitamin C vs synthetic vitamin C. Also, there are lots of naturally-occuring molcules you don't want in you.

I wouldn't say "inherently better", but...

Through evolution, we've adapted to molecules present in the environment, and because other organisms have similar tolerance to toxins, eating them is usually safer than eating a random substance.

It's just a heuristic, of course, reasonable people may disagree. I was just pointing out that the OP's position is not "obviously dumb".

I disagree that it's reasonable to be wary of chemicals - it's a triumph of rubbish marketing.

It goes both way: companies producing artificial products (including drugs) have massive advertising budgets, but there's no ad touting the merits of oranges and tap water.

Honest question: if I find a new mammalian species and try to sell its meat, do I need FDA approval?

EDIT: In your top post, you're objecting to the man's argument that "it's natural therefore it's safe". I agree with you that it's naive in this context. I guess I misread your post and argued against something else :/

Flows both ways, though. Through evolution, our biological enemies have come up with the nastiest chemicals they can.

Natural vs. "man made chemicals" people often forget that on the whole, Nature is out to kill you. The most potent known toxin is called Botulinum toxin and is named after the bacteria that produces it (or vice versa).

I don't think the intent is to kill with poisons as much as to serve the ultimate goal of most organisms, self preservation.

How about some supporting evidence? (I assume that you're excluding man-made molecules which are also found in nature, but if you're not, please explain where you're putting them and why.)

http://en.wikipedia.org/wiki/Carrageenan#Health_concerns

Have you ever had a look at the ingredients in non-dairy creamer: http://foodconstrued.com/2011/01/cream-in-my-coffee/

A much better word would be "artificial" or "synthetic" additive IMHO.