New research has suggested that the nationwide rise of the potent greenhouse gas sulfuryl fluoride comes almost entirely from termite fumigations in the greater Los Angeles area.
Sulfuryl fluoride is a common treatment for drywood termites, bedbugs, cockroaches, and other pests. The Dow Chemical Company developed the gas, also known by its brand name Vikane, in 1959.
Concentrations of sulfuryl fluoride have grown exponentially worldwide: In 1978, it was 0.3 part per trillion. Today it’s more than 2.5 parts per trillion.
The latest research has found that one hot spot in the United States—the greater Los Angeles area—has the highest emissions of sulfuryl fluoride. In the region, sulfuryl fluoride concentrations have topped 400 parts per trillion at times between 2015 and 2017, said graduate student Dylan Gaeta of Johns Hopkins University. The second-highest emissions came from California’s Bay Area. The rest of the country releases barely any emissions.
“We expected to see little splotches of emissions throughout at least some other parts of the country,” Gaeta said. “The fact that we are seeing almost all of it from California? That was the shocking part.”
NOAA’s monitoring network does not extend to Florida, however, and the state does not track sulfuryl fluoride use. “It is possible that Florida is also emitting, and then it’s just not being detected by the NOAA network,” said Gaeta. He presented the research, which has not yet been peer reviewed, at AGU’s Fall Meeting 2021.
For years, the insecticide was thought to be relatively harmless when it came to global warming.
To use the substance, fumigators first cover a building with an airtight tent. They fill the building with gas and let it do its work. Afterward, workers open windows to air out the building, releasing the gas to the atmosphere, where it was believed to break down relatively quickly.
