Each summer an oxygen-starved, lifeless "dead zone" swells in the Gulf of Mexico from the toxic nitrogen fertilizer that runs off farms in Midwestern corn country.

dead zone

But now that dead zone is expanding -- dangerously. And it's starting to put the health of a nearly $3 billion fishing industry and an entire ecosystem of aquatic life at risk.

Last year the dead zone covered an area the size of New Jersey -- 7,700 square miles.

The culprit? The USA's corn ethanol boom. That's the conclusion of new research published in the Proceedings of the National Journal of Sciences.

It was carried out by two professors, geographer Simon Donner of the University of British Columbia and atmospheric scientist Christopher Kucharik of the University of Wisconsin - Madison.

Their findings are quickly adding to the alarm over America's ill-fated practice of using food crops for fuel.

The authors explain the urgency. A huge boost in corn production from US government ethanol mandates has sent record amounts of nitrogen fertilizer down the Mississippi River and into the Gulf of Mexico. Once in the Gulf, the nitrogen breeds oxygen-eating algae that blossom on the water's surface, depriving creatures of their lifeline.

More nitrogen means even deader zones in the Gulf and elsewhere. And with streams, rivers and other waterways struggling more than ever to drive out excess nitrogen naturally, the situation is going to get worse. Everywhere. So predicts another piece of new research out of the Oak Ridge National Laboratory, published in the journal Nature.

The researchers there have discovered that bodies of water have historically been able to remove nitrates through a natural "denitrification" process. But they seem to be losing their knack for it. Now, more and more nitrogen is left for the algae to take up, leaving growing swathes of dead waters in their wake.

Has the nitrogen load from corn kernel production become too much for America's waterways to handle? Looks that way, with the worst yet to come.


The US energy bill that was signed by President Bush in December 2007 mandates farmers to produce 36 billion gallons of biofuels by 2022. Corn ethanol is capped at 15 billion of that amount by 2015.

That goal is more than three times the nation's corn ethanol production in 2006.

And it spells trouble for those who reap their livelihoods from the Gulf. Donner's team predicts that meeting that goal would increase nitrogen runoff in the Mississippi River Basin as much as 34 percent in just 15 years.

A disaster in the making, writes Donner:
The nitrogen levels in the Mississippi will be more than twice the recommendation for the Gulf. It will overwhelm all the suggested mitigation options. This rush to expand corn production is a disaster for the Gulf of Mexico. The US energy policy will make it virtually impossible to solve the problem of the Dead Zone.
What to do?

Donner is not without solutions. If America refuses to shrink its insatiable appetite for biofuels, then it can always stop eating meat. Seriously. From his blog:
If the US pursues this biofuels strategy, it will be impossible to shrink the Dead Zone without radically changing the US food production system. The one option would be to dramatically reduce the non-ethanol uses of corn. Since the majority of corn grain is used as animal feed, a trade-off between using corn to fuel animals and using corn to fuel cars could emerge.
Interesting. But does Donner really believe that's a viable alternative?