The culprits? Tiny splinters - whiskers, they're called - that sprout without warning from tin solder and finishes deep inside electronics. By some estimates, the resulting short-circuits have leveled as much as $10 billion in damage since they were first noticed in the 1940s.

Now some electronics makers worry the destruction will be more widespread, and the dollar amounts more draining, as the European Union and governments around the world enact laws to eliminate the best-known defense - lead - from electronic devices.

"The EU's decision was irresponsible and not based on sound science," said Joe Smetana, a principal engineer and tin whisker expert with French telecommunications equipment maker Alcatel-Lucent SA. "We're solving a problem that isn't and creating a bunch of new ones."

Typically measuring under a millimeter long, tin whiskers look like errant strands of static-charged hair, erupting in every direction from tin-based materials like solder. Their cause is hotly debated. Other metals also grow whiskers, but not like tin.

Trouble arises when the whiskers bridge separate parts of increasingly miniaturized circuit boards. They also can flake off and interfere with sensitive optics.

While scientists debate their cause, they agree on one thing: Small amounts of lead mixed with the tin have been remarkably effective at preventing whisker eruptions for decades.

Lead, however, is a serious health concern. In children, it can cause learning or behavioral problems and has been associated with anemia and kidney problems. In adults, exposure has been linked to high blood pressure and reproductive organ damage.

Last year, Europeans barred the toxic metal from most electronics to prevent its being incinerated or accumulating in dumps after computers and other gadgets are tossed out. Similar measures are being considered or are already in place in other countries, including Japan, China, South Korea, Argentina, Australia and the United States.

Some companies say the EU rules threaten the reliability of their products, exposing them to unknown risks and possibly threatening people's safety.

But EU officials say the regulations banning lead, cadmium, mercury and three other hazardous substances are needed to protect people and the environment.

They also note that many types of electronics are exempt from the law, including military and other national security equipment, medical devices, and servers, data storage computers and telecommunications gear that use leaded solders.

Exemptions are also granted when alternatives to the hazardous materials don't exist yet, or because the substances can't be replaced without jeopardizing safety.

Still, even some companies with exemptions say it's getting harder to buy the leaded parts. They worry about the increased risk of pure-tin parts, the culprit behind the most devastating tin-whisker-related failures.

"Over time (the failures) are just going to get worse and worse and worse," said Jim McElroy, executive director of International Electronics Manufacturing Initiative, or iNEMI, a group of big electronics makers, government agencies and other parties active in tin whisker research.

"Even if the military is exempt forever, they will be forced to convert because they can't get the components they want," he said. "And that will eventually happen across the board."

Tin whiskers have left a trail of destruction in a string of important machinery, chronicled in an extensive database of publicly disclosed failures kept by researchers at NASA's Goddard Space Flight Center in Greenbelt, Md.

Last year, for example, NASA engineers testing parts for the space shuttle Endeavour discovered that millions of tin whiskers were causing an electronic box to inaccurately point the shuttle's engine, knocking the rocket's trajectory off-kilter, according to Henning Leidecker, chief engineer of the electronic parts office of NASA's Goddard and a tin whisker expert.