NIST Working On "Deathalyzer"

coondoggie writes to mention that a new optical technique for sensing small amounts of molecules in a person's breath has been developed by a researcher for the National Institute of Standards and Technology. The goal is to create a fast, low-cost method for detecting disease. "In this approach, NIST researchers analyze human breath with 'frequency combs,' which are generated by a laser specially designed to produce a series of very short, equally spaced pulses of light. Each pulse may be only a few million billionths of a second long. The laser generates light as a series of very narrow frequency peaks equally spaced, like the teeth of a comb, across a broad spectrum."

couldn't they use this to detect other things?

[aldousd666]

Like marijuana or cocaine? Wasn't one of the primary complaints against legalizing marijuana from a law enforcement perspective the lack of ability to monitor the level of intoxication of a user? Well there you go. Hippies rejoice. It's a step toward your green [smoke] goal. Tree hugging anyone?

Dogs are trained to smell skin cancer

[JonTurner]

This is basically an electronic nose, (an astoundingly sensitive one) which could be used for many purposes such as narcotic interdiction, explosives detection, etc. And could be used to detect various vorms of cancer:
http://news.nationalgeographic.com/news/2006/01/0112_060112_dog_cancer.html [nationalgeographic.com]

"Our study provides compelling evidence that cancers hidden beneath the skin can be detected simply by [dogs] examining the odors of a person's breath," said Michael McCulloch, who led the research.

Two additional anecdotal stories of early cancer detection by dogs:
http://www.usatoday.com/news/health/2004-09-24-cancer-sniffing_x.htm [usatoday.com]

Re:Sound like a form of hi-tech infra-red scan.

[repapetilto]

Yea to me it looks like spectroscopy, except instead of first purifying the sample then dissolving it, its some sort of gas chromatography device that separates the different molecules for you (based on how much each type sticks to the walls), then you scan whatever absorption frequencies your looking for with the laser and compare the energy you detect with what the laser put out. Wherever there was absorption(depends on the frequency and molecule) will tell you what was in there by comparing the spectra with that of known molecules. The trick here seems to be that you don't have to prepare the sample at all, and they use a series of ultra-short laser pulses rather than normal em radiation in order to detect low concentrations easier. Cool idea.

Also hydro-peroxide is the name for a different molecule (actually class of molecules) than hydrogen peroxide, R-O-O-H vs H-O-O-H respectively. And I assume the nitrate/nitrate ions are either hydrogenated or they regulate the pressure and lower it enough for the ion to enter the gas phase. That diagram has a "tedlar bag" attached for some reason though, so maybe theres some extra reaction going on between certain molecules and the tedlar, or the bad could be made of tedlar, thats not clear.

Diabetes - acetone on breath

[Anonymous Coward]

I had a mate who wasn't drinking test positive on a couple of breathalizers, but a blood test came up negative. He was arrested and it shook him quite badly. This is a whole new way of ruining lives.

Since you used the term 'mate' to describe your friend, I'll assume that you're perhaps in Australia???

People who have diabetes (even mild forms that otherwise do not need insulin treatments) often exhale small amounts of acetone, as that is a byproduct of improper metabolism of sugars in diabetics. Acetone causes the ethanol sensing mechanism in handheld breathalyzers to go ape-shit crazy and falsely over-report the presence of ethyl alcohol. Police officers in the USA are supposed to be trained specifically to be on the lookout for this situation in order to get certified to use the breathalyzer and be able to use its test results as evidence in a court of law.

Also people on low-carb diets will have elevated levels of acetone in their bloodstream.