In Your Cosmetics...What You Don't Know...Still Won't Kill You Pt. 1

I was asked a great question about David Suzuki and his cosmetic chemical comments, and what should you be concerned about in your cosmetics. This is a great question. I am going to break this up into two separate entries because I need to get on my little soap box here for a minute. This question highlights the huge disconnect that exists between science and the general public. This is a shame, because science is awesome, and makes huge impacts on our everyday lives. 

Part 1 of this entry is concerned with dealing with scienc-y info you come across from the mass media, facebook cult, politicians, and lobbyists. It is very frustrating as a scientist to see one little misused claim cause out right panic over a chemical. So I am going to break down a few things you can do to better understand what the real science issues are and what is the junk. 

1) Consider the source and be skeptical. Who is presenting the data? What research was done and by whom? What is the sources agenda? What are the other sides of the research? Was it peer reviewed?-  These questions will help you sort out how much you should be buying into the claims. If the source is a politician hoping to get through a law for stricter regulations on a chemical, they are going to present any research on the chemical that is negative and leave out the positives. Remember too that news media is a business, therefore they want their stories to sell and what better way to sell then to embellish (just a little) the concerns about the chemical. All credible science will have peer reviewed research to back up any claims they make.

2) Beware of Radicals. I hate radicals, they cause all sorts of problems in chemical reactions, the cause all sorts of problems in the environment, and the cause all sorts of problems in society. Anyone who is so far to one side of an issue as those people who fall into the "radical" category are not known well for presenting all the facts and for having the very best logic-no matter what side of the issue they are on! David Suzuki IS a radical, and he feels that he no longer has to support his claims. Reading his article on cosmetics, I must say I am appalled. He speaks very generally, skirting around what any potential issues are. His link to the "dirty dozen" is extremely misleading. Some points are also incorrect. (I will deal with these in part 2) but it is very important to be aware of that. Where is the research links? Who was it done by? He gives none of this, which going back to point 1 has me skeptical over what he is trying to get across.

3) Correlation does NOT mean CAUSE. This is so important! Many studies are done by correlating two particular data sets eg. Ben & Jerry Sales vs the # of murders, to determine if there may be a relation between the two. Positive correlations mean that, continuing with my example, the number of murders increased as the number of Ben & Jerry Sales increased. A negative correlation means the opposite, the number of murders decreased as the number of Ben & Jerry Sales increased. However, this does not mean that it CAUSED anything. The above example is a true study, often used to illustrate this point. It was found that there is a positive correlation between the number of murders and the sales of Ben & Jerry. Does this mean that eating ice cream will cause you to be a murderer? I think we can all agree that would a pretty ridiculous claim, but you see my point. When a news article says MAY CAUSE (or variations of) that means that a positive correlation was observed, but whether an actual cause exits remains to be seen and is probably under further investigation. It is worth knowing that there is a correlation, but don't jump too quickly to the panic side of things. 

Please check out this link for a laugh and an illustration of my point: The Science News Cycle

A chemical we should all be concerned about is: dihydrogen monoxide. This chemical is a colourless, odourless liquid. In large amounts it is known to cause suffocation. It contains the a hydroxide group, which has been known to form radicals that can cause cancer, and DNA damage. It has been responsible for the destruction of settlements in extremely large amounts. It has been shown to easily erode land, and is often used to dissolve a variety of different chemicals. In its solid form it has been linked to the deaths of thousands. And we are all exposed to large amounts of this chemical EVERYDAY! What is it? Dihydrogen-means two hydrogen atoms. Monoxide-means one oxygen atom. H2O-oh it is WATER! 

The Stomach: Acid-Base Chemistry

What is in the stomach? Good old hydrochloric acid. I have previously mentioned HCl can do some damage to your skin. But why then does it sit harmlessly in your stomach? This is because your stomach is lined with an acid resistant mucus. I say resistant because the mucus does need to be replenished and if it isn't, you start getting ulcers. 

But that mucus ends at your stomach. Your esophagus and your small intestine-the two pieces of your digestive system on either side of your stomach-do not have the mucus. This is why on those mornings after a night of drinking, and therefore a morning wrapped around the toilet, your throat may burn. That is because the acid burns the tissues as it makes a mass exit from your stomach. This is also why people with eating disorders that involve purging often has eroded teeth, gums, and other lesions in their mouth and throat. The continuous passage of acid over those tissues burns them, eventually leading to serious damage. Side note: while HCl can burn your tissues it would be a poor choice if you wanted to dissolve a dead body. 

So what can you do if the acid in your stomach gets to be too much of a problem? Neutralise it of course! What neutralises acids? Bases! Acid + Base = water + salt. This is always. And this is a very important reaction. To neutralise stomach acid, you don't want too strong of a base so sodium bicarbonate, NaHCO3, will work just fine.  HCl + NaHCO3 = NaCl (the salt) + H2CO3 (carbonic acid) which dissociates (quickly) into H2O (water) and CO2 (carbon dioxide). The CO2 is a gas and this is why taking an antacid may make you gassy. So if you want to buy an antacid, you can. But you can also just use the sodium bicarbonate you have in your cupboard. It is probably in box marked Arm and Hammer Baking Soda.

Do All Bugs Need Drugs? What is An Antibiotic...

The subject of today's entry is "antibiotics". What are they? What do they work on?

When we use the term "antibiotic" generally we are referring to a pharmaceutical drug that kills bacteria. Technically speaking this term could actually apply to any chemical that kills bacteria; however, when you read the term used on say "antibacterial soap" it generally means that some sort of drug is an additive. 

Focusing our discussion down to antibiotics as pharmaceuticals, they are designed to inhibit some part of the bacterial life cycle. Inside a cell, (all cells) there are many complicated biochemical reactions going on. An antibacterial drug is generally designed, or discovered, to inhibit, or change these pathways is some way. Different drugs do different things. Penicillin, and drugs in the penicillin family (generally end in "cillin" eg amoxycillin) prevent bacteria from multiplying. This then allows your body's natural immune system to kill the foreigners. Other antibiotics, clindamyacin, vancomyacin (I may have misspelled these-my apologies), are designed to inhibit different pathways in the bacteria. 

Some antibiotics are stronger than others, possibly targeting many pathways. Some are weaker.   Penicillin is generally weaker, where clindamyacin is quite strong. Usually, you take an antibiotic appropriate for the virulence of the bacterial infection. A simple staph (staphylococcus-the normal skin bacteria) infection isn't going to require a harsh antibiotic like clindamyacin. That particular antibiotic is saved for infections with more robust bacteria that have proven to be resistant to other antibiotics.

Why might this be important? Well don't forget that you have natural bacterial symbiotes that are actually helpful to you. For example, the E. coli bacteria in your intestine are essential for digestion. Taking antibiotics don't just kill the unwanted, interloping bacteria, but will also kill the good ones too. This is one of the side effects of antibiotic use is diarrhea. Yeast infections in women are also common because there are natural bacteria in the vagina and killing them can result in an upset in the balance of the natural fauna, giving yeast a chance to get out of control. Uncomfortable, but treatable.

One thing that all of us need to be diligent about is responsible antibiotic use. By using them inappropriately means that the bacteria will evolve (yes we believe in evolution on this site) and then the antibiotics will no longer be effective. Using antibiotics with a viral infection is one of the common ways to misuse antibiotics. Colds, flus etc. are viruses and therefore antibiotics are not going to work. Soap and hot water is effective enough for the most types of germs that you want off your hands. Alcohol based hand sanitizers are also useful.

Household Cleaners: Chemistry Under the Kitchen Sink

I have recently been asked questions regarding household cleaners, so this entry is designed to answer them as thorough as possible. 

When many people hear the word "chemical" they often picture people in CSI type labs, with fuming beakers, in labs coats and safety glasses, but chemicals are every where. You are made of chemicals, you are dressed in chemicals, and you are eating chemicals. When you consider this much broader definition you can now see how the potential for reaction is everywhere. The main source of chemicals in our homes is generally under kitchen sink: cleansers-that is if you believe in cleaning your house. We can have cleaners for all different types of reasons, which means that the litany of chemicals under your sink can be quite vast (especially if you are a very good friend of mine who treats cleaning her house as a form of exercise and meditative relief-you know who you are) and that means that some of them will be incompatible-or to be more specific they will react. 

Bleach + ammonia = bad! We all have heard this, but why? Household bleach is a 5% solution of sodium hypochlorite, NaOCl, in water.  Window cleaners, like Windex, are made from ammonia: NH3. 

NaOCl + NH3 = NH2Cl + NaOH

NH2Cl-chloramine. This is unstable and explosive. It is also possible to over chlorinate to get NHCl2 and NCl3, which are equally terrible for you. Interesting side note: replacing the chlorine atoms with iodine atoms, it becomes possible to make nitrogen triiodide, NI3. This is a contact explosive and a favourite practical joke among chemists. We use it demos because by touching the stuff with a feather it is possible to make it explode. You can also put it on the underside of a toilet seat, so when someone sits down they are greeted with a large, ear-ring bang. My personal favourite April Fools Day joke is to put it the key holes of doors so that when people insert their key it causes the explosions. (Note: these aren't TNT level structure ruining  explosions, just a loud bang type). 

"Why is ammonia a useful glass cleaner?" Fingerprints are a usual problem on glass. A fingerprint is caused by the oils on your skin, which are made of fatty acids. As the name implies, they are acidic. When the acids react with a base, like ammonia, they are converted to water soluble salts and are washed away. (The free-basing of cocaine hydrochloride uses the same chemical principle to make crack.)

The other household question I got was "why should you where gloves when using CLR?"

CLR removes calcium, lime, and rust. These are all metal based problems and are easily eaten away by an acid. My favourite way of cleaning up calcium blockages in my own lab equipment is using 6 molar hydrochloric acid. A more dilute solution of this is made and packaged and sold to consumers as CLR. But being an acid, it is possible for it to cause burns on your skin, so wearing gloves will protect you skin. 

Why Doesn't Diet Coke Taste as Good as Regular Coke?

This is one of the first questions my sister asked me in her suggestion of writing this blog, so it gets to be the first one answered.

The taste difference between the two arises from the fact that regular Coke is sweetened with sugar, your basic everyday C12H22O11 table sugar. And not just a little, but a lot of sugar. Which is where the calories come from. Diet Coke, on the other hand, is sweetened with an artificial sweetener: aspartame. Aspartame is a modified amino acid that is relatively sweet, but is not absorbed by the body, therefore cannot be used for energy, and thus reduces the number of calories in the pop. Now, while aspartame is sweet, being a different molecule and having a different shape than sugar it does not fit into the same into the taste receptors on your tongue and thus tastes different. Now some people, if you can believe it, actually like the taste of aspartame therefore they think that the Diet Coke actually tastes better. But like my sister, I am partial to sugar so I prefer the full calorie regular Coke. 

 

Ask a Chemist: So it begins...

I am starting this blog at the request of my sister. Science, and specifically chemistry, impacts all our lives in a very important capacity everyday. But many people are unsure of how this chemistry works and when you ask some chemists, or the omnipotent Google, the answers are often rather complex and full of jargon. So this blog is designed to answer your science and chemistry questions without being too technical or condescending. Hopefully I will be able even get some of you realising how awesome chemistry is! So if you have a question, leave me a comment and I will make it the subject of my next post and there you will find your answer!