Several southern U.S. senators voiced their support this week for fair trade laws in the catfish industry in a letter to the head of the U.S. Commerce Department.

Sen. Jeff Sessions, R-A, was among six others — two each from Mississippi, Louisiana and Arkansas.

In the letter, the senators expressed concern over the effect of cheaply imported catfish from Vietnam and suggested the Commerce Department maintain its current pricing methods. Sessions led a similar effort in 2013.

“The catfish industry is vital to many rural communities throughout the southeastern United States,” Sessions said in a statement. “American workers are not asking for special favors, only a level playing field that allows them to compete in a global market.”

The letter specifically asks the Commerce Department to continue enforcing U.S. trade laws on foreign catfish exports. Trade laws currently require a surrogate country be set for Vietnam, which exports millions of tons of catfish to the U.S. each year. Surrogate countries set a pricing standard for economies controlled by the government. Vietnam’s current surrogate country is Indonesia.

Sessions says Indonesia provides a more realistic pricing model than Bangladesh, which previously served as the surrogate country.

“It is essential that Indonesia remain a pricing surrogate to ensure that U.S. industry recovers and grows,” he said.

Regardless of the surrogate selection, local catfish farmers say foreign imports remain far too cheap by comparison and often contain harmful pollutants. Restaurants often choose the foreign product and sell it at the same price, in turn causing less demand for domestically produced catfish, according to sixth-generation farmer Will Pearce.

“It’s just a cheap product coming in,” Pearce said. “Many of the imported fish contains harmful chemicals that we haven’t been able to use for 20-plus years. With all the legislation, we are just trying to get a level playing field.”

On average Pearce said foreign fish cost one dollar per pound less than domestic fish.

“The thing is restaurants label it as U.S. catfish and sell them for the same price,” he said. “They just make more profit off of an inferior product.”

Pearce said ensuring a level playing field is especially important to the Black Belt. Thousands of catfish farms populate the area. Alabama ranks second in catfish productions, behind Mississippi.

The move is the second, recent catfish-related regulation Sessions has pushed. The first was an amendment to the farm bill for a catfish inspection program.

The program would shift catfish inspections from the Food and Drug Administration to the U.S. Department of Agriculture. Currently, the FDA conducts random testing at ports when catfish are imported. With the new program, the USDA is expected to be more proactive in its inspections and catch contaminated catfish, according to Catfish Farmers of America President Butch Wilson.