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Lurking among us are foolish folks who fork out cash for deodorants even though their armpits don’t smell.
This is the take-home message of an article in the Journal of Investigative Dermatology that’s been making the rounds of science news sites and blogs. It’s a fun study, but the results aren’t really that surprising.
Researchers have known for years that some people in Europe (2% of the population) and most people in China, Japan, and Korea are fortunate enough to have two copies of a recessive gene that makes their armpits relative* stink-free zones.
That’s because the gene codes for a protein involved in transporting molecules out of special sweat glands that appear in your armpits at puberty. These stink-producing glands are called apocrine glands, and they differ from eccrine glands, which are found all over your body and produce the salty fluid we commonly associate with sweat and body temperature regulation.
Apocrine glands typically excrete all manner of waxy molecules that armpit bacteria love to feast on. It’s the leftover, metabolized molecules, such as trans-3-methyl-2-hexanoic acid, which give many human bodies that oh-so-ripe odor.
Because the difference between stinky and stink-free folks is a gene involved in transporting armpit molecules, it’s pretty likely that people without body odor have a dysfunctional transporter. Although that’s not yet been proven, it’s a reasonable theory.
For example, people with odorless armpits also produce a dry white earwax, instead of a yellowish wet version. Presumably, the transport machinery that isn’t exporting bacteria food in the armpit isn’t exporting a yellowish fluid in the ears either.
What’s really new in the article is simply the observation that among the 2% of folks in the UK who probably don’t need to apply deodorant, 78% still do.
OK, so why is this not really surprising? Continue reading →
Obama, Sarkozy and Cameron skipped the opening ceremonies for the International Year of Chemistry in Philly, Paris and London, but props go to Germany’s head of state, Angela Merkel–formerly a theoretical physicist/chemist herself–for showing up at the IYC shindig here in Berlin today.
She said some things we’ve heard before, such as how chemists could help solve energy problems (with, say, nanotechnology) and how they already had (by developing energy efficient materials for improved housing insulation, for example). She also talked about Marie Curie as a role model, the promise of young scientists and the irony of the public’s not entirely positive perception of chemicals given that we’re all composed of them.
But instead of rushing in and out, Merkel stayed around long enough to award three teams of very cute elementary students awards for a competition called Formula One. Effectively, the teams had to build a chemical battery and then race a home-made car for 20 meters. And again, instead of shaking everybody’s hand and moving along, she grabbed the moderator’s mic and started interviewing the kids about their projects. Pretty classy.
Organizers chose the lovely Radialsystem as their IYC launching site. The red-brick water pumping station nestles the Spree River right at the border of the former East and West Berlin. It was renovated in 2006 into a space for the arts and renamed Radialsystem. There’s lots of dance and theater to be seen here, but the last time I stopped by was to listen to some guy’s brain (alpha) waves as he sat on stage with headphones, himself listening to a sequence of conversations which ranged from boring bureaucratic negotiations to presumably more interesting bedroom dialogues. This is also where Merkel spoke at the 2009 Falling Walls conference, on the 20th anniversary of the fall of the Berlin Wall, where scientists gathered to discuss the ”walls” that needed to fall in science to improve the world. Continue reading →
After Thursday’s sequence of enthusiastic speeches that repeatedly declared that chemistry can solve all the worlds ailments (health, food security, energy etc), the second day of the opening ceremonies of the International Year of Chemistry at UNESCO headquarters in Paris got a bit more concrete on how this actually might happen, with talks from academics and industry leaders on how chemistry can improve nutrition, agriculture, medicine and materials for alternative energy.
But amidst the celebratory feeling in the main auditorium, a different kind of discussion happened at the press conference yesterday that is probably epitomized by reporter questions that went alot like: “So how do you address the criticism that this is all just a self-congratulatory jamboree for the chemical industry?” or “Exactly how is chemistry going to save the world?” The answer IYC organizers gave was not precisely specific or clear, and it landed hard in the press room. I suspect this isn’t the last time similar questions will be voiced.
The IYC is an opportunity for chemists to celebrate their discipline, but it’s also clear that organizers also want to redeem the reputation of chemistry in the minds of a public that often sees the science as a source of pollution. IYC organizers said they want to remind the public that chemistry is the source of materials many people can’t live without—headache remedies and other drugs, toothpaste, iPhones or your favourite pair of sneakers.
To do so, there have been lots of launches in the past two days. There was the video aimed to make 16-20 year-olds think chemistry is sexy. Or the announcement of the world’s first and largest concurrent measurement of pH and chemical content of local water supply by elementary and high school students from Buenos Aires to Bombay. NASA is here promoting it’s earth observatory images. And of course many people were enthused about January 18th’s “Women Sharing a Chemical Moment in Time” (cue Whitney Houston) where female chemists met at 8 am in time zones around the world.
So chemists, celebrate and be joyous. But judging from the questions posed by the only non-chemists here at the opening ceremonies—the media—it might behoove you to be prepared to get specific about how chemistry benefits humanity if you want the excitement to spread outside the chemistry community. And don’t forget to temper those festive chemical soliloquies with some of the risks of molecular science, at the same time as you celebrate many of the benefits.
Sometime before 600 BC, Mayan artists painted one of the few frescoes–still in existence–that displays the domestic life of normal people in this ancient civilization (other Mayan frescoes display the lives of deities and rulers). The frescoes were found in a pyramid at the Calakmul archaeology site in Mexico. Calakmul is one of the biggest Mayan sites around, but it hasn’t been excavated to the same extent as say, Tikal, which had a cameo in “Return of the Jedi” as the Ewok planet and is also host to a constant throng of tourists.
As they work, archaeologists at Calakmul have tried to protect the wall frescoes from the subtropical climate of Mexico, but a mixture of light, temperature, humidity and sulfate-based pollution was starting to hurt the precious frescoes. That’s where Piero Baglioni comes in. He’s a physical chemist at the University of Florence, who has earned a certain amount of fame for his development of nanoparticles that can clean up frescoes harmed by pollution or by other restoration attempts. In particular, the nanoparticles can deal with the salts that lead to pigment deterioration and flaking of the frescoes. (Baglioni’s nanoparticles can also help reverse ill-thought-out attempts to protect frescoes by covering them with vinyl or acrylic polymers, a problematic restoration technique that can cause complete powdering of a painting. As recently as a decade ago, polymers were widely applied to give frescoes some water repellency but they’ve caused havoc at other Mesoamerican sites, including Tehotihuacan and Mayapan, Baglioni says.)
In the case of Calakmul, the frescoes were suffering from sulfate salts, but six months after application of a “humble” calcium and barium hydroxide nanoparticle solution, flaking of the frescos was reduced (Chem. Eur. J. 2010, 16, 9374).
See the before (left panels) and after (right panels) below.
When humanity’s predilection for perfume meddles with the sense of smell of insects and animals, it can sometimes be fortuitous. Case in point: the discovery that Calvin Klein’s Obsession perfume lures jaguars, tigers, and other big cats to expectant nature photographers and videographers. But meddling with odor receptors of other creatures can prove problematic. For example, the cosmetic and food fragrance 1-methylbutyl 3-methylbutanoate elicits aggressive defense behaviour in hornets. Sometimes people meddle with an insect’s ability to smell sexual pheromones as a means to combat invasive species. In 2007, California’s agricultural industry tried spraying an overwhelming amount of invasive moth species pheromone onto fruit crops because they hoped the signal overload would confuse the male moths and disrupt the species’ mating cycle–a solution that led to serious controversy.
The question that Richard Bolek, a PhD student, and his adviser, Klaus Kümmerer, at the University of Freiburg Medical Center, in Germany, want answered is whether some of the fragrances we use—in perfumes, personal care products, and cleaning agents, which get released into the air or down the drain–are inadvertently interrupting some of the chemical communication networks that benign or beneficial insects and animals rely on. Continue reading →
The Washington Post‘s continued coverage of the massive Kellogg’s 28 million cereal box recall in June, when 2-methylnaphthalene from the packaging percolated into the cereal, and yesterday’s news that Congress is now investigating that recall are good reminders that for any food you consume, a small part of the wrapping inevitably ends up in your body, too. Ditto for pharmaceutical drugs.
Last summer I wrote about how food and pharma companies are starting to deal with these packaging leachables, and so a couple of people at C&EN asked me to speculate on how the 2-methylnaphthalene had ended up in America’s Froot Loops.
According to the Kellogg’s press release, the voluntary recall occured due to an “uncharacteristic off-flavor and smell coming from the liner in the package.” The CDC’s website notes that naphthalene is often found in moth balls and deoderant, but it can also be found in resin (presumably how Kellogg’s thinks the 2-methylnaphthalene ended up in the cereal box liner) and printing dye ingredients. Substituted naphthalenes have high vapor pressure, which means they can migrate through all sorts of packaging, including cardboard and polyolefins.