The Compound Syria Supposedly Used as Chemical Warfare

There are a number of different gasses that have been used in chemical warfare, but the most likely culprit in the case of the recent Syrian civil war conflict is Sarin. Sarin is a potent nerve agent (a phosphorus containing molecule that inhibits nerves from communicating to organs), and is fairly easy to synthesize as it only requires two reactants, one of which is isopropyl alcohol, and the other methylphosphonyl difluoride.  These reactants are combined when the nerve gas is released since this molecule is unstable in the P-F bond. The toxicity of this compound reaches about 500 times that of cyanide. The molecule was originally synthesized in 1938 by a German company in sight to produce an insecticide, but proved to be more useful in chemical warfare after the German army began testing in 1939.

What makes the use of chemical warfare, subject to such serious allegations? They are weapons of mass destruction that are cheaper, less destructive on the environment, and selective on anyone without a gas mask. So a regime, such as the Syrian army, can use it to eliminate it's citizens, while their army wears protective gas masks. And, as a nuclear blast would demolish a city, a chemical bomb leaves the buildings intact, but with a high death toll. These weapons aren't used to fight a war, but to exterminate an entire population within the desired vicinity. This is why chemical warfare has been banned.

Monocrotophos: A Deadly Insecticide

A recent incident in India has left 23 children dead as a result of cooking oil contaminated with monocrotophos. Being as this was a free meal by government, aimed to keep 120 million children well fed and nourished, this turns some heads.

This molecule has been used as an insecticide, but has since been banned in Canada and the US, along with a number of other countries. They have failed to keep a ban on such pesticides due to the issue of having to feed so many hungry mouths, and needing a high crop output. In the countries where it is still legally used as a pesticide it is required to dilute it to 16% by volume of water. But in this case there was no dilution, indicating that there was direct contact with the poison after the oil processing.

This then becomes a question of who is responsible for insuring this doesn't happen again? One option is to enforce the correct usage and safety for this material, but considering the large illiteracy of the population, and difficulty in setting up an enforcement task, this poses much difficulty.

My opinion in how to prevent something like this from happening again is to enforce limitations on the manufacturer of the insecticide, the ones who enticed the Indian government into lifting the ban with their low price point. To either enforce a ban on synthesizing the compound all together, or to impose a concentration restriction, making the manufacturer dilute before the product is sold

4-Methylimidizole, a Pepsi Additive

Recently the news has been discussing Pepsi's additive 4-methylimidizole in the caramel colouring of their popular drinks, with the fact that the Centre for Environmental Health has deemed it unsafe. Now should you go into your fridge right now and toss all of your Pepsi into the garbage? No. Although a study that was performed in 2007 gave results showing that 4-methylimidizole has carcinogenic properties in mice and rats, keep in mind that this is at an extremely high dose (115mg/kg of body weight) and the dosage that a normal consumer will receive showed no effects.

So why is this molecule in Pepsi in the first place? It comes with the additive caramel colour, which is produced by a separate manufacturer and is listed as Caramel Colour on the ingredients list.  This molecule is made as a product of the Maillard Reaction, the browning of food, and in this case being the reaction to produce the caramel colour. But the problem with their method in producing the caramel colour is that they use a method with a higher concentration of ammonia, which incidentally ends up producing more 4-methylimidizole than other methods. Since this has come out, the US caramel colour manufacturers have changed their recipe to adhere to the people's reaction, lowering the overall concentration of 4-methylimidizole.  This has yet to change the formulation in other parts of the world though.

Ricin: A Potent Poison

Now I don't really talk about anything on this site that deals with anything biochemistry related, but I will make this an exception due to the state of current events. Ricin might be a word that you have heard recently in the new, about the poising attempt on President Obama by an Elvis impersonator.  For those who don't know what Ricin is, it is a protein originating from the same plant that gives you castor oil. It's job in the body is a nasty one, as it inhibits protein synthesis (which is pretty much everything important in a cell), more specifically it acts upon the ribosome (a small organelle which synthesizes proteins). It's categorization of inhibitor is a Ribosome Inactivating Protein, which cynically has the acronym RIP.  Although this is a very deadly poison (a gram worth to kill), there does exist an antidote, but the survivors will have major organ damage and will have a shortened life expectancy.

Source:
Wikipedia

Egyptian Blue: Calcium Copper Silicate

In a recent article by Scientific American, a story is told of Calcium Copper Silicate (Egyptian Blue) being the first artificial pigment made by humans, and soon to be utilized, once again, as a nano ink for biomedical imaging.  I'm not going to go over the details of the article, but I will present some background information of this soft blue colour.

Being the first recorded synthetic pigment, you may ask how it was originally synthesized.  The first procedures, in 3000 B.C., involves the heating of sand, calcium carbonate, copper, and an alkali substance to obtain this blue pigment having a composition of CaCuSi₄O₁₀.  The reaction below is a general understanding of the reaction, where the molecules can be variable in a number of different ways.

Cu₂CO₃(OH)₂ + 8SiO₂ + 2CaCO₃ → 2CaCuSi₄O₁₀ + 3CO₂ + H₂O

The blue colour comes from the absorption of the copper, which can range from the blue, seen above, to a much darker blue, depending on how pure the mixture is. But what wasn't known at that time, was that when irradiated with visible light, the compound emits IR photons, which is the property that will conduct the imaging technologies.

References:
Via: Scientific American
Wikipedia

What is Triclosan and Why is it Being Banned?

Triclosan has been in the media recently, in it's battle with regulation in its existence in many cleansing products.  In a recent article by the C&EN News they reported that "Minnesota state agencies will be able to purchase only soaps and detergents that are free of the antibacterial ingredient triclosan. State officials say they are concerned that the chemical has been linked to endocrine disruption and the growing threat of antibiotic resistance."

What is Triclosan, and how long have we been in contact with this reportedly "harmful" chemical? 
It has been used commonly in many different products since 1972 when it first became apparent that it reduced bacterial activity.  Such products as toothpaste, mouthwash, deodorant, trash bags, kitchen tools, and many other areas where antibacterial products seemed appropriate for manufacturers to use for preserving their products, or making their cleaning products more affective.

Why is it being banned?
It is being banned for a number of reasons.  First of all, as mentioned by C&EN, the risk of upsetting endocrine function.  This hasn't necessarily been proven in human subjects (other than slightly affecting the immune system, which may be due to the vast number of bacteria in, and around the body ¹), but it has been reported that the North American Bullfrog's endocrine system becomes compromised under low doses of Triclosan ².  Another reason is that it has been proven that it decreases bacterial species diversity, in other words, selects for antibiotic resistance.  The third reason is that it can be harmful to the environment for the reasons stated above (i.e. disrupting aquatic bacteria), along with Triclosan's byproducts such as dioxins being harmful.

How to avoid using products with Triclosan?
If you don't wish stay free of this product, read labels, and educate yourself of what is in the products you are using. It may also be listed under trade names of UltraFresh, Amicor, or BioFresh.

References:
Via: C&EN
1. Erin M. Rees Clayton, Megan Todd, Jennifer Beam Dowd, Allison E. Aiello. "The Impact of Bisphenol A and Triclosan on Immune Parameters in the U.S. Population, NHANES 2003–2006". Environ Health Perspect 119 (3): 390–396. doi:10.1289/ehp.1002883

2. Nik Veldhoen, Rachel C. Skirrow, Heather Osachoff, Heidi Wigmore, David J. Clapson, Mark P. Gunderson, Graham Van Aggelen and Caren C. Helbing. "The bactericidal agent triclosan modulates thyroid hormone-associated gene expression and disrupts postembryonic anuran development". Aquatic Toxicology 80 (3): 217–227. doi:10.1016/j.aquatox.2006.08.010

4/4/2012 - What Makes Old Paper Yellow?

I apologize for once again another prolonged absence, for I have started physiotherapy and the pain has risen significantly, and writing a blog post was the least of my concerns.  I don't currently have my organometallic text book on me at this moment, so I thought I would diverge from the organometallic history for a moment to talk about paper.
If you have ever studied upon an old piece of paper, you would have noticed that the paper is no longer white but appears yellow.  If you were me, you would have had risen two questions, one, whether the paper was made in this tone, or two, whether some chemical reaction had been performed on the paper to make it this colour.  So I decided to look at what actually happens to the paper and have found that what makes it yellow is the formation of the molecules called Chromophores.  This process is done through the oxidation of cellulose over time creating many different products, but of most importance the aldehydic chromophores responsible for the yellowing.
Finding this information receives it's importance when researchers want to look into restoring old papers through a reduction process removing these chromophores.

Source: Science Magazine