Arysta LifeScience Corp., Cary, N.C., has suspended sales of all formulations of its soil fumigant, Midas, in the United States, effective immediately.

Existing supplies and tanks should be returned to Arysta, said an Arysta spokeswoman, who didn't want to be identified.

If a field has been already treated with Midas, Arysta will continue to steward the product.

In addition, the company will continue to maintain the federal Midas label and will assess the maintenance of state labels, she said.

The decision to halt sales was made as part of an internal review and was based on economics of the U.S. market, according to a news release.

"It's a financial decision," the spokeswoman said. "It will allow Arysta to refocus its resources on other business."

The fumigant continues to remain a viable product outside of U.S. markets, and Arysta will continue to support the product elsewhere, she said.

Midas contains the active ingredient methyl iodide and received a one-year conditional registration from the Environmental Protection Agency in September 2007 and a full federal registration the following year.

At the time of registration, Arysta billed Midas as a replacement for the fumigant methyl bromide, which was considered by many to be an ozone depleter.

Midas was labeled on many of the same crops as methyl bromide, including strawberries, peppers, tomatoes and cucurbits.

Most states subsequently registered Midas.

It had been applied to more than 17,000 acres in the Southeast, according to Arysta figures.

California became the 48th state to register the product in late December 2010.

The controversial decision marked one of the last made during Gov. Arnold Schwarzenegger's administration.

Several groups petitioned incoming Gov. Jerry Brown to rescind the registration, saying the fumigant posed safety risks to farm workers, nearby communities and the environment.

Brown had yet to act on the request.

Six commercial applications of Midas on a total of 15 acres have been made in California, said Lea Brooks, a spokeswoman for the California Department of Pesticide Regulation in Sacramento. The largest was 5 acres.

Two each were made in Fresno and Santa Barbara counties, and one each was made in San Joaquin and Tulare counties.