Insecticide chemical is a powerful greenhouse gas.
The federal government is going to take some significant steps to reduce global warming gases. Carbon dioxide is the main target, but there are other types of greenhouse gases. Lester Graham spoke with one researcher who found a potent greenhouse gas lingers in the atmosphere much longer than previously thought:
January 26, 2009
We hear a lot about carbon dioxide as a greenhouse gas. But there are other chemicals that trap heat and contribute to global warming. One of them is an insecticide used to fumigate termite-infested buildings. It's called Sulfuryl fluoride. That insecticide is four-thousand times better at trapping heat than carbon dioxide. It's been estimated that Sulfuryl flouride hangs around in the atmosphere for five years or so... but new research shows that it lasts a lot longer than that:
Mads Sulbaek Anderson is working with other researchers at the University of California-Irvine published a study in the journal Environmental Science and Technology.
He's with us now... first, how is this termite insecticide used?
"Well, it's used in a number of applications. What the fumigators do is, they basically cover the house in a giant tent. And then you fill up the house with this compound, and over the span of a few days, one or two days, this compound acts like a pesticide- it kills all of these bugs. After that time span, you remove the tent, and make sure that all of this compound evaporates and dissipates."
What did you discover about how long this insecticide actually stays in the atmosphere?
"The usual routes by which pollution is removed from the atmosphere has to do with reactions, and there's something called an OH radical, a hydroxyl radical in the atmosphere. That's the usual cleaner of the atmosphere. In this case, this radical didn't react at all with the compound - we couldn't detect anything."
Is this a significant contributor to global warming, or greenhouse gases?
"It's still a question of how much is actually present in the atmosphere right now. But, we know how much is used every year of this compound. And so this compound, right, it's 4,000 times more efficient in trapping the heat compared to carbon dioxide. But of course, there's not much of it out in the atmosphere yet. But it's more a precautionary tale, because other compounds are being phased out for other reasons and so sulfuryl fluoride could take over for those applications, if we don't think twice about this. And it stays around for at least a few decades. So, it's not an enormous problem by itself- we have to focus on the real problem, which of course is due to emissions from burning fossil fuels. But this compound too contributes to the warming of the atmosphere, or could potentially do it."
Mads Sulbaek Anderson is a researcher at the University of California-Irvine. Thank you.
"You are very much welcome."