It's pumped through vacuum chambers to ensure a clean, sterile environment for the manufacture of the chips that go into TVs and computers. But this “missing greenhouse gas”, with a global warming effect 17,000 times that of CO2, is deadly to

Technology firms began to use nitrogen trifluoride (NF3) in the manufacture of computer microchips and flat-screen TVs in the late 1990s. It was thought a safer alternative to PFC gases, which were known to contribute to global warming. The gas was less likely to escape into the atmosphere. However, it had the potential to cause much more environmental damage if accidentally released.

Now scientists are worried that more of the gas may be released during its use than previously assumed, reports the LA Times.

“We don't know if 1% is getting out or 20% is getting out, but once you let the genie out of the bottle you can't get it back in,” said Michael J. Prather, co-author of a study of the gas.

When released, the gas survives in the atmosphere for 500 years, trapping heat and contributing to rising global temperatures during this time.

Reacting to the growth in popularity of flat-screen TVs and computer screens, plants in the U.S. and Korea last year stepped up production of nitrogen trifluoride. By 2010, world production is expected to reach 8,000 tonnes a year – the equivalent of 130 million metric tonnes of carbon dioxide, the most well-known greenhouse gas.

There are currently no international guidelines in place to limit the production of the potentially devastating gas. NF3 is not covered by the Kyoto Protocol, having only come into widespread use after the international agreement on the reduction of greenhouse gases was drawn up.

The University of California is now researching a method to measure how much of the gas is already trapped in the Earth's atmosphere, so that the scale of the threat can be determined.