Despite the protests of more than 50 scientists, including five Nobel laureates in chemistry, the U.S. Environmental Protection Agency on Friday approved use of a new, highly toxic fumigant, mainly for strawberry fields.

Methyl iodide is a neurotoxin and carcinogen that has caused thyroid tumors, neurological damage and miscarriages in lab animals.

Many of the chemists -- who use small amounts of methyl iodide in their laboratories to attach molecules and are careful to avoid exposure -- said they are shocked that the EPA is allowing its use as a pesticide because it can drift into neighborhoods and pollute groundwater.

"It is potentially really toxic, and it's certainly very reactive. From what we know about its chemistry, we know this stuff reacts with DNA. It mutates it. So it's prudent to be as careful as you can with it," Bergman said in an interview Friday.