Consider a fire hydrant. To most people, it has the potential to save lives. Some see a more immediate gain: Its brass nuts can be twisted off and sold for a few cents at the nearest scrap metal shop.

Similarly, some view cemeteries not as sacred resting spots for the dead but as troves of bronze plaques and statues, worth hundreds of thousands of dollars and free for the taking. And the historic bell at St. Mary's Cathedral in San Francisco was just 2.7 tons of pure copper to the thieves who stole it from the churchyard last week.

Since the early 2000s, rapid industrialization in Asia and elsewhere has inflated the international demand for scrap metals. This in turn has driven up the metals' value, leading to another trend: More and more Americans seem to be seeing dollar signs where they used to see everyday metal objects.

"It's a delayed effect where, as the price of metal goes up, slowly you begin to see the rise in theft of scrap metal as people begin to recognize that they're able to get more cash for it," said Brandon Kooi, a professor of criminal justice at Aurora University in Chicago. Kooi, who wrote a 2010 report on scrap metal theft for the U.S. Department of Justice, told Life's Little Mysteries he has found a rapid rise in this type of crime nationwide, with some areas seeing double or triple the frequency of a decade ago. "These are crimes of opportunity, in that there is metal everywhere," he said. [Where'd That Bridge Go? The Weirdest Metal Thefts]

Thieves recently made headlines stealing everything from cars' catalytic converters — which are coated with platinum, palladium and other precious metals worth $200 — to beer kegs, of which $50 million worth is sold for scrap each year. X-ray films have been pilfered from hospitals because they contain traces of silver. Two brothers were arrested last week in Pennsylvania for allegedly dismantling an entire 50-foot-long steel bridge and selling 15.5 tons of it for $5,000.

Combination of causes

Several factors have combined to drive the upsurge in scrap metal theft in the past few years, Kooi said. For one, industrialization is occurring internationally, especially in China and India. "Because of the massive amount of construction that's happening, there's a need for building supplies. Meanwhile the U.S. has been industrialized for quite some time, which allows our trash to become their gold, so to speak," he said.

The U.S. is the No. 1 exporter of scrap metal, and because of increasing demand, its annual exportation to developing nations tripled from 6 million to 18 million tons between 2002 and 2007. The market value of many metals saw a parallel rise. According to the London Metal Exchange, the price of a pound of copper rose from 65 cents in 2002 to $4 in 2006 (with a slight drop in the years since). [Why Did Gold Become the Best Element for Money?]

Gold, platinum and other precious metals have risen in value amid a financial crisis that lowered investors' confidence in other forms of currency.

Aggravating the problem are the home foreclosures that accompanied the collapse of the house market in 2008. Copper pipes were increasingly stolen from houses abandoned by homeowners and banks.

Scott Berinato, executive editor of CIO, a security news publication, believes frequent media reports of metal thefts also have contributed to the rise. "Thieves have caught on: There's metal everywhere and much of it is, understandably, unguarded," Berinato wrote in a recent CIO article. "You don't notice how much metal there is for the taking until it starts getting taken."

Although some thefts can be attributed to people made desperate by the economic downturn, Berinato and Kooi say many thefts are linked to drug use. Addicts often require quick access to small amounts of cash and are willing to take huge risks to get it, such as scaling 200-foot-tall utility poles for the few dollars worth of copper at the top, or breaking into high-voltage electrical substations. Though drug use has not increased in recent years in the United States, more drug addicts may have cottoned on to metal theft as a way of making a quick buck, Berinato explained.

Scrap yard solutions

Until recently, there was very little regulation of the metal resale market in the United States, which allowed thieves to find ready buyers. Because of public and political awareness of the burgeoning problem of metal theft, that's changing.

"Clearly the scrap dealers are needed to turn theft into cash, and consequently they become the solution to the problem," Kooi said. "Legislative changes have been made at the state level in many states to get the dealers to become more uniform and standardized in the way they operate."

The president of a scrap metal dealership in the Philadelphian suburbs says he works hard to minimize the amount of stolen goods that move through his facility. "When we see something that is brand new and it makes no sense that it would be scrapped instead of returned to the retailer, we would automatically refuse to buy the material," said Jacob Cohen, president of the Robert K. Kurtz Co. in Trevose, Pa.

"On the other hand, a lot of stuff that comes in could be stolen and you just don't know," Cohen added. "So we follow the state guidelines by ID'ing the sellers and photographing all those items, so that even if we process it and it is stolen, we can match the photograph with an individual and give the authorities the information they need."

He predicted more states will institute such policies. "These are nuisance crimes that are becoming a major issue."

Crime psychology

Scrap metal thefts are crimes of opportunity rather than crimes of passion, and Kooi says the best prevention is to make the opportunities less tempting.

"In virtually every decision we make in life, we use cost/benefit analysis. Clearly, in many locations the benefits of stealing scrap metal have greatly outweighed the perceived costs. As scrap metal dealers manage their organization more effectively, and make it more challenging for thieves to successfully sell metal, we hope that will make the costs greater than the benefits," he said.

Kooi believes ongoing research is needed to monitor whether state regulation of scrap yards is effective in reducing crime rates.

This article was provided by Life's Little Mysteries, a sister site to LiveScience.

This article was reprinted with permission from LiveScience.

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