CHEMisperceptions: roundup and quiz answers

A note: My site started malfunctioning last night. So CJ was kind enough to post our roundup on his site. I apologize that this post isn't quite what I wanted it to be. Hopefully I'll have my site back to "normal" soon. One other note: I couldn't get all of the analysis of everyone's results for my quiz finished. But, I've given a summary of the questions and the molecules discussed.

Well ... I'd call that a success. The four of us are entirely grateful for all of your participation this week. I think that it's plainly safe to say that we really don't know what we're talking about. And, as always, we had the most fun in the comments sections.

I kicked things off on Monday with a discussion on chemical toxicity and safety. The three things that I really wanted to get across are:

1. All chemicals have some benefit and some risk. We need to understand both aspects.
2. Even "safe" or "common" chemicals can be dangerous. But that doesn't mean we need to be overly concerned with them or with more dangerous chemicals for that matter. We just need to... (see point 1)
3. Chemical exposure comes with an immediate and a delayed risk. Getting back to ethanol, drinking too much in a short period of time is hazardous to our health, and continuously drinking smaller amounts over a long period of time is also hazardous.

Some ideas that came up in the comments included breaking away from my comparison of chemical exposure with exposure to ethanol to the risks involved with driving. Commenters seemed to like this conversational approach. The excellent xkcd infographic showing the relative danger of different radiation exposures was brought up as the gold-standard for risk education.

On Tuesday, CJ talked about the what, how and why of chemistry and how it's unlikely that the general public correctly perceives these questions. In the comments, he and the readers talked over a number of different solutions to addressing these misperceptions:

• Videos: The C&EN video series was praised for being a potential means of communicating chemistry well. Paul thinks that we need a telegenic chemistry advocate (one commenter objected.) CJ thinks videos would be an excellent way of explaining difficult concepts. 
• Not being pharma-centric: Commenters expressed different ways to explain their work rather than say "this molecule might kill cancer"; analogies to carpenters and/or artisans were suggested.
• Being patient: Matt and David pointed out that we don't have to teach with explosions and mayhem; persistence and paying attention to what works well will be helpful.

On Wednesday, Paul moved our conversation to energy policy and specifically talked about the downside of corn-based ethanol production. In the post, Paul advocated for more solar energy and battery-based energy while talking about the useless subsidies being used to develop corny ethanol.

In the comments, discussion quickly drifted to expanding the number of energy sources used. And, in what I find to be very interesting, there was talk about local energy vs. energy at a distance and trying to figure out what sorts of infrastructure would be needed to maintain a decentralized power grid.

Leigh certainly had the find of the week yesterday with her reference to the list of chemicals allowed in the production of certified organic food. I highly recommend you read through the list. It's enlightening! As was the rest of Leigh's post on the meaning of "organic" and the history of how that word has taken on all of its meanings.

So ... back to my quiz results. What I was trying to do is show how some cherry-picked data can easily confuse people (even chemists) when trying to estimate the risk of chemical exposure. Below, I've shown the questions along with a brief explanation of the chemicals and actual exposure risks involved.

1. Would you rather eat meat that has been infused and colored pink with nitric oxide (NO) or carbon monoxide (CO)?

NO is an pollutant that is produced when fuels are burned in the presence of air. NO is known to be toxic at high enough concentrations. Carbon monoxide is an air pollutant that is produced when fuels are burned in the presence of air. CO is known to be toxic at high enough concentrations. Scientists think to seem that both of these molecules play a role in normal biological processes.

It drives me crazy when meat is packaged under CO. CO binds to the protein, myoglobin in meat, keeping it from turning brown. However, this brown color is an excellent indicator of how fresh the meat is. Nothing angers me more than bringing home seemingly fresh, pink ground beef only to find that the inner portions of the meat are brown. NO also interacts with myoglobin. NO is what gives barbecued meat its distinctive smoke ring. Although some of the molecules created while barbecuing are cancer causing (to some extent) we disregard this fact because we enjoy it so much.

2. Which would you rather dump on your dining room table? Molecule 1 or Molecule 2?

Molecule 1 is used as a strong oxidizing agent in many industrial reactions. Molecule 1 will also produce chlorine gas (very toxic) when mixed with a common household cleaning agent. Smelling molecule 2 causes strong reactions in humans. Molecule 2 has been used in the past as the starting point to make explosive compounds.

In this question, molecule 1 is bleach (NaOCl, sodium hypochlorite) and molecule 2 is ammonia (NH₃). I think its safe to say that both compounds can be dangerous. I also think its safe to say that most people aren't overly concerned about having these dangerous chemicals in their house. We don't fear the things we're used to.

3. Which molecule would you rather dump on your hands? Liquid 1 or Liquid 2?

Liquid 1 is industrially produced and highly flammable. Liquid 1, at a high enough concentration, is a strong irritant of your eyes and lungs. Liquid 2 contains molecules that are known to lead to cardiovascular disease. There are many "healthier" industrially produced substitutes to Liquid 2, even though Liquid 2 is produced from animal by-products. 

Liquid 1 is acetone ... which is the main ingredient in fingernail polish remover ... which people put on their hands all the time. Liquid 2 is melted butter ... I do like me some melted butter.

4. Which molecule would you rather take a big smell of in its pure form? Diacetyl or toluene?

Diacetyl is the artificial butter flavoring that is used in microwave popcorn. Toluene is a solvent used in some types of glues. Toluene is the active chemical that creates a "buzz" when glue is sniffed. 

Diacetyl in large quantities can be pretty hazardous. Toluene is hazardous too. But we're more concerned about the toluene than the diacetyl due to the larger amounts of it that we're exposed to.

5. Which would you rather drink? Molecule 1 or Molecule 2?

Molecule 1 has an LD50 of 9000 mg/kg when administered orally to rats. [That very roughly equates to just over 1 liter (0.26 gallons) for a 91 kilogram (200 pound) person.] Molecule 2 has an LD50 of 12600 mg/kg when administered orally to rats. [That very roughly equates to just over 0.9 liters (0.24 gallons) for a 91 kilogram (200 pound) person]. For reference, water has an LD50 of 90,000 mg/kg when administered orally to rats.

Molecule 1 is ethanol. Molecule 2 is glycerol. Which would you rather drink?

6. Which would you rather take as a medication for severe inflammatory pain. Molecule 1 or Molecule 2?

Molecule 1 is derived from bee venom. Molecule 2 is extracted from a flower.

Molecule 1 is melittin, the primary component of bee venom. Even though there's no evidence that there is any medical benefit to using it, some people still do. Molecule 2 is heroin. When it was first medically approved, doctors lauded the fact that it caused no side effects and wasn't addictive. (Heh).

7. You've just seriously sprained your knee. What would you rather take to soothe your injury? Liquid 1 or molecule 2?

Liquid 1 is a tea made by steeping a liquid with a certain type of flower. Teas of this type have been used traditionally around the globe to help cure ailments of this sort. Molecule 2 is an industrially produced compound. The FDA, in 2009, reduced the maximum dosage of this compound by 35% from its previous levels.

Liquid 1 is a comfrey tea, a naturalist medication, that has been widely used. The flowers that are made to steep these teas have very dangerous alkaloids in them that can cause serious harm to those who ingest them (HT to David Kroll). Molecule 2 is acetominophen. The FDA reduced the dosage amounts of acetominophen in both 2007 and 2010.

8. An industrial application calls for a solvent to be used to assist in performing a vital reaction. Should the company use benzene or water?

Benzene is a known carcinogen. However, it can be separated from the final product that the corporation is making. Excess, impure benzene, can be burned, producing energy (and carbon dioxide) for further industrial use. Water is a "green" solvent. However after using water in an industrial application, water cannot just be released back into the environment. It must be purified. This is a very energy-intensive process that will necessitate burning lots of fossil fuels and producing a large amount of pollutants. Use of water for industrial applications drains the water resources available for other human needs.

This is something that is commonly misperceived. In a case like this, using benzene is certainly more environmentally safe than using water. But, because it's water, we automatically "think" that it's better.

9. A can containing tomatoes needs to be lined with a plastic that will protect the tomatoes from degrading or being infested with bacteria. Should the lining be made with BPA or pine oleoresin?

BPA has been in the news a lot lately due to the fact that it is ubiquitously used by industrial food suppliers as well as producers of consumer plastics. BPA has been implicated as the cause of several developmental diseases. BPA has been studied by the FDA. Pine oleoresins are naturally produced. Acidic solutions (like those found in tomato juice) will degrade pine oleoresins. And use of these compounds over BPA will increase the likelihood of bacterial infection. Pine oleoresins have not been studied in as great of detail as BPA by the FDA. 

This gets back to my point from the other day: BPA is cheap and effective and, thus, ubiquitous. It is because BPA is everywhere that it's so dangerous. If it weren't, there would be almost no reason to worry about it.

10. It's Friday ... What are you doing still reading this blog. Inconceivable! Go enjoy yourself!



-mrh