Two Suffolk fumigation companies have applied for an air quality permit to continue their operations and will host an informational meeting together in August to answer the public’s questions about their business.

Royal Fumigation and Western Fumigation both use a chemical called methyl bromide — a toxin to humans — to kill pests on some shipments leaving from or arriving in the United States. The two companies have long been competitors, but they teamed up when they learned the Virginia Department of Environmental Quality would be requiring both to obtain permits for a major source of air pollution.

The Material Safety Data Sheet for methyl bromide notes that it is fatal to humans if inhaled in large quantities. In smaller quantities, it is a severe irritant to the upper respiratory tract, skin and eyes.

Both companies began operating in the city several years ago, without knowing they were required to apply for an air permit. Royal Fumigation is located on Finney Avenue, while Western Fumigation is near the Pruden Center on Pruden Boulevard.

“This is the first time we’ve ever been required to apply for an air permit,” said Anne Bookout, vice president and general counsel for Royal Fumigation. “The DEQ feels that under the terms of the Clean Air Act, we need an air permit.”

Bookout said Royal Fumigation did not think its operations fell under the terms of the federal Clean Air Act, because it does not produce toxic chemicals, but only uses them. The companies already are regulated by the U.S. Department of Agriculture.

“We don’t produce a chemical, we simply apply it,” Bookout said. “Nobody really thought of fumigation as applying to the Clean Air Act.”

The companies receive material, mostly logs, and treat them for pests before they are shipped.

“We in the U.S. have certain pests that nobody else wants,” Bookout said. “They require us to treat the logs before we send them to these countries.”

In addition to logs, Royal Fumigation also treats wood packing material such as pallets and crates, and crops such as tobacco and cotton. They sometimes also treat materials coming into the country that the USDA has quarantined because it found pests in the shipment.

The materials are lined up inside the building and covered with a tarp. Workers wearing safety gear spray the methyl bromide under the tarp, and expose the material for a certain amount of time. The tarp is then removed, and the chemical is aerated using large exhaust fans and released from the building slowly.

According to Bookout, the amount of the gas that makes it into the surrounding air is “a matter of some contention.”

“I don’t think we really know,” she said. “I couldn’t tell you how much.”

Methyl bromide is used because it is one of the most effective pesticides in existence, Bookout said.

“It kills all life stages of the pest,” she said. “With quite a few insects, it’s very difficult to kill the eggs. This works against all life stages, and it works quickly. It is volatile, so it will evaporate and we don’t have to worry about soil or water contamination.”

Martha Craft, vice president of communications for Rollins, Inc., the parent company of Western Industries, confirmed that Western Fumigation conducts substantially the same operations at its facility.

“We are performing the required fumigation of commodities coming in or out,” she said. “These are USDA requirements.”

The companies will host an informational meeting Aug. 18 at 6 p.m. at the Hilton Garden Inn Conference Center, 100 E. Constance Road.