Washington — Scientists predicting the biggest-ever "dead zone" in the Gulf of Mexico are blaming Midwestern corn grown for ethanol for higher levels of pollution escaping down the Mississippi River.
"In the past several years, there's been an expansion of corn, which has the highest fertilizer per acre ... and that's for biofuels." said R. Eugene Turner, a Louisiana State University professor who directed the study into the gulf's water quality.
Turner's research team reported this week that an area of oxygen-deprived water in the Gulf of Mexico is expected to grow to more than 10,000 square miles this year. The largest the area has ever been measured was in 2002, when it was about 8,500 square miles.
Scientists from the Louisiana Universities Marine Consortium said that this year's "dead zone" could be the largest since measurements began in the 1980s. The scientists used computer modeling for their prediction and will take shipboard measurements in July throughout the gulf.
The dead zone is caused by an abundance of nutrients from sources that include fertilizers needed for corn.
"The nutrients act as a fertilizer just like they would in a corn field," causing excessive growth of algae on the ocean floor, Turner said. The algae consumes oxygen, forcing aquatic creatures like fish and shrimp to flee or die.