The current movement toward increasing the approved ethanol blend rate in gasoline has some senators asking for further study before raising the limit. The senators are concerned that more ethanol production will adversely impact livestock producers and increase food costs.

In a letter to EPA Administrator Lisa Jackson Tuesday, Sen. Jim Webb (D-VA), and 20 other senators, requested more comprehensive ethanol testing before an increase in the ratio is approved, according to the

The senators ask that air quality and technical issues be studied, as well as potential adverse effects on consumers and livestock and poultry producers during a global recession. The letter was also sent to USDA Secretary Tom Vilsack.

“While increased production and use of ethanol has helped advance the goal of energy independence, it has had the unintended consequence of sharply increasing costs for corn and other sources of feed,” says Webb. “I believe it is important to fully understand the impact that increasing the use of corn ethanol would have on food costs.

The current approved level of ethanol in gasoline is 10 percent.

See more on senators’ letter.