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Scientists Discover Why Your Dirty Laundry Stinks (discovery.com)
HughPickens.com writes: Discovery News reports that dirty laundry smells bad because of certain chemicals called volatile organic compounds, which can't always be washed out on an eco-friendly 20C cycle. Researchers identified six volatile organic compounds (VOCs) on dirty t-shirts and socks. "The need to conserve the environment by reducing the wash temperature and the use of biodegradable washing products have grown in importance in the new millennium, making this type of research more high profile," says Professor John Dean. The researchers gave 6 men and two women a new pair of socks. They asked the volunteers to wash their feet with tap water and dry them before wearing the socks for at least 10 hours in a specified type of shoe. They then put each sock into a separate sample bag and stored them in the dark overnight. The researchers graded each sock and t-shirt on a scale of 0 (no malodor) to 10 (malodorous) by smelling them. To determine the chemicals present, samples were taken from each one. Items were then washed on a cold cycle using unscented detergent, and resampled before they were dried, at which point researchers took one final series of specimens. Following a method called static headspace-multi-capillary column-gas chromatography-ion mobility spectrometry (SHS-MCC-GC-IMS), six main VOCs were identified as the main culprits behind smelly clothing. Each one left its own scented signature. Butyric acid, for example, produced a rancid butter-like odor, while 2-heptanone created a banana-like fruity smell. "The work is fascinating as it links an everyday event -- the washing of clothes -- with cutting-edge research," says Dean. "In this particular research project we applied a new and innovative analytical technique for the detection of volatile compounds found in laundry items. We hope this provides a way of analyzing the effectiveness of different washing techniques."
>> laundry smells bad because of...chemicals...which can't...be washed out on an eco-friendly 20C cycle
>> conserve the environment by reducing the wash temperature and the use of biodegradable washing products
Long story short, they seem to be telling us at least one of two things:
- you shouldn't bother with "environment friendly" detergents and washing techniques if you have kids, dogs or ever work out
- we now know why filthy hippies smell that way
I'm pretty sure if it came to "family smelling bad" or "saving the twin-tuffed arselizard" my wife would be on the side of "nuke them from orbit - it's the only way to be sure." Personally, I can't see washing temperatures dropping at all, but I would expect the equivalent of a "detergent catalytic converter" to become part of our washing machine wastewater system in twenty years - there aren't many good reasons to keep flushing that stuff into our sewers and septic tanks.
Even though it appears environmentally friendly to wash the underwear in a low temperature with detergent designed for it that doesn't mean that it solves all problems. Especially fungal spores may reside in the fabric after a low temperature wash, while washing in 60 degrees Celsius or higher will kill them.
I know this from personal experience - changing the washing temperature to a higher temperature helped me to get rid of the fungal infections I repeatedly had on my feet.
So if you suffer from repeated fungal or bacterial problems, try raising the washing temperature.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
When I was in high school, I took Chemistry II. Part of that was to do an advanced experiment of some kind. I ended up picking one out of a book the teacher had. It involved butyric acid.
The school chemistry lab was very well stocked, though many of the chemicals were quite old. For example, we had a large brick of sodium in a jar filled with kerosene. First thing, the teacher told us, "Absolutely leave that thing alone." He went on to tell us that it could explode if dropped in water.. He was serious, and we took him seriously.
But I digress. The lab also had the butyric acid I needed. I did the experiment (not very successfully, IIRC) and then proceeded to my next class. It was a computer class, on the original TRS-80 "microcomputers."
Everybody thought the computer teacher was a wonderful teacher and a very nice guy, including me. Just after class started, he said, "What's that smell?" We were all a bit puzzled, but we all started sniffing around, and the teacher ended up honing in on me.
I smelled of rancid butter. Having found the culprit, the teacher told me, "Get out - just get out."
I meakly protested, "Don't I need a hall pass?"
"I'll bring you one, just go."
It turned out that some of the butyric acid had vaporized and adhered to my clothes. I somehow managed to make it through the rest of the day by issuing various warnings and apologies in my remaining classes. I think we had to throw the clothes away.