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Golf With FirePower, Goaty Perfume

by Alex Scott
April 13, 2014 | A version of this story appeared in Volume 92, Issue 15


Credit: UC Irvine
In this clip, Earthman demonstrates the hazards of a titanium alloy golf club.

Want your golf game to be as hot as Tiger Woods’s? If you use a titanium alloy club for your next shot, you might get your wish—but not in a good way.

Credit: UC Irvine
Fore! Earthman shows how titanium alloy golf clubs can generate 3,000 °F sparks.
A golfer creates sparks with a golf club when it strikes a stone.
Credit: UC Irvine
Fore! Earthman shows how titanium alloy golf clubs can generate 3,000 °F sparks.

That’s because when golf clubs with titanium-coated heads strike a stone, they can generate sparks. And those sparks can exceed 3,000 °F and stay hot for long enough to ignite dry foliage and start a wildfire, according to a recent study by researchers at the University of California, Irvine.

Team leader and chemical engineer James C. Earthman investigated the phenomenon by re-creating golf course conditions in a lab and making observations with high-speed cameras and scanning electron microscopy. His team found that when a club head grazes a rock, titanium alloy particles break off and react violently with oxygen or nitrogen in the air to generate a tremendous amount of heat. The researchers also determined that no such problem exists with steel clubs (Fire Mater. 2014, DOI: 10.1002/fam.2235).

Orange County, Calif., fire investigators commissioned Earthman to undertake the study in the wake of recent blazes at Shady Canyon Golf Club, in Irvine, and Arroyo Trabuco Golf Club, in Mission Viejo. In both cases, golfers used 3-iron titanium alloy clubs that they say created sparks and subsequent fires.

The concern now is that such blazes could become more common as titanium alloy golf clubs, which are 40% lighter than their steel equivalents, become more popular. Orange County Fire Authority has asked golfers with titanium alloy clubs to keep their cool if they end up in the scrub. The duffers should ask fellow golfers whether it would be possible to improve the position of the ball or take a penalty shot rather than take a dangerous swing.

An entirely different kind of sparking caught the attention of some Japanese scientists. Researchers led by the University of Tokyo’s Yuji Mori have discovered a citrus-scented pheromone excreted by male goats that jump-starts female goats’ reproductive systems (Curr. Biol. 2014, DOI: 10.1016/j.cub.2014.01.073). The study is the first to show that a certain pheromone in mammals activates the central reproductive system of the opposite sex, according to the team.

Credit: Shutterstock/C&EN
B-a-a-a-d idea: Not set to become a best-selling fragrance among humans.
Perfume bottle with a picture of a goat on it and the words “Jean-Paul Goatier.”
Credit: Shutterstock/C&EN
B-a-a-a-d idea: Not set to become a best-selling fragrance among humans.

Not only does 4-ethyloctanal rev up the female goats’ reproductive endocrine system, the researchers say, the chemical also oxidizes to become 4-ethyloctanoic acid, a key ingredient of the animal-like odor known for decades to attract female goats to males.Yukari Takeuchi, one of the researchers, opines that the male goat is pretty clever and marvels at his economical use of a single molecule to both put come-hither mojo on a she-goat and to start her reproductive engines.

But the findings are unlikely to trigger a surge of interest in pinpointing an equivalent human pheromone. Some studies have noted that humans respond to steroid hormones androstenes and estrenes, but there is no general consensus as to their effects or, indeed, whether they have any effect at all, says Tim Jacob, professor emeritus and olfactory expert at Cardiff University, in Wales. As he succinctly puts it, “Goats are not humans!”

Fragrance manufacturers won’t exactly be rushing to incorporate 4-ethyloctanal into their perfumes either. No matter how stylish the bottle, it won’t hide the goaty odor of the compound’s oxidized form.

Alex Scott wrote this week’s column. Please send comments and suggestions to


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