U.S. food and chemical companies are spending millions to defeat a ballot measure that would make Washington State the first in the U.S. to require producers to label foods that contain genetically modified crops.

The Grocery Manufacturers Association, which represents more than 300 food and beverage companies, has spent nearly $11 million to oppose the initiative -- about half of the $22 million raised by opponents of the labeling law. Supporters of the measure have raised a paltry $6.8 million, Reuters reports.

Nestle USA, General Mills, PepsiCo and Monsanto and DuPont are some of the large corporations that have contributed to the campaign against the bill. 

Washington State Attorney General Bob Ferguson (D - Wash.) filed a lawsuit against the GMA on Oct. 16, alleging that it illegally concealed contributors’ identities while collecting $7 million.

There is disagreement over whether genetically modified crops pose a health risk to consumers. Producers say the crops boost farmer productivity and cite studies that show they are safe for human and animal consumption. Opponents say hundreds of studies indicate that these crops are unsafe.

In a sample of 413 registered Washington voters, 46 percent said they would support the voting law, while 42 percent said they would vote against it, with a 5 percent margin of error.