Is Gulf Seafood Unsafe to Eat After Oil Spill?

May 26, 2010 — -- Forget about high technology and sophisticated sensors. The first line of defense in the effort to protect the public from seafood contaminated by the giant oil spill in the Gulf of Mexico will be the human nose.

Oil from the April 20 explosion of the Deepwater Horizon offshore drilling rig is already flooding into some of the most productive coastal areas in the world, threatening a wide range of seafood. No one knows yet how dangerous that might be to humans, but public officials charged with ensuring the safety of food products are already training regulators literally to sniff out chemicals that could pose a threat.

"The human nose is a powerful instrument," said Steve Otwell, who leads the University of Florida's professional seafood sensory school. Otwell will help train about 25 persons from the National Marine Fisheries Service and the federal Food and Drug Administration on the Gainesville campus beginning in a few days.

Human sniffers have been used to detect tainted food for years, and although it may not be as precise as some high tech instruments, it's quick, it's cheap, and it works, Otwell said in a telephone interview.

Human Nose Can Play Role in Detecting Unsafe Seafood, Professor Says

"You will have the purists, and the lawyers, and everyone else say we need to have a very sensitive chemical method to really determine what's there," he said. "And that's absolutely true. But the amount of time, the lack of such instrumentation, and the costs make it impractical to depend on that technology to scrutinize the variety of seafood and the variety of areas that's involved with this particular spill."

The instruments that are available are not effective for every potentially dangerous chemical, and it can take days -- and sometimes weeks -- to get results.

So Otwell, a professor of food science and human nutrition at the university's Institute of Food and Agricultural Sciences, is quite serious about the role human noses will play in determining whether the bounty from the gulf remains safe.

"It is a science and the human nose can indeed detect levels that can provide us with a safety level, but the nose has to be trained. And some noses are better than others," he said.

Normal Noses Can Be Trained to Sniff Out Suspect Foods

But that doesn't mean he's searching for gifted noses. "Normal people have the capability to do this," he said. "This is not some super human who's in the nose Olympics."

Shortly after the spill occurred Otwell and his colleagues began collecting seafood from the gulf to generate base line data of what untainted food should smell like. They will add samples that have been exposed to the gulf spill, as well as samples that have been "spiked" with contaminants, providing references to guide the sniffers.

Since some people are better smellers than others, any suspected food products will likely require approval by a series of well-trained noses.

If a product flunks a sniff test, it will then be "bumped up to the next level and that's when you do chemical analysis," Otwell said. And some testers will probably have to try a few bites before the product can be cleared.

This is likely to become a very controversial issue in the weeks ahead, because some decisions -- like whether to close or reopen a fishery -- will have to be made quickly, perhaps even before chemical analysis can be completed.

Expert: Most Dangerous Chemical Levels Would Be Pungent and Easily Detected

Closing a fishery can have a devastating effect on families whose livelihood depends on harvesting the gulf's bounty, and it may not always be clear that the need is real.

"In every oil spill, hundreds of chemicals are involved," Otwell said. Some might not be visible, but in most cases, he said, they will probably smell, at least a little.

A tiny amount of contamination might escape detection by even the best trained nose, but Otwell believes that dangerous levels would be pungent, and thus easily detected.

"Can chemicals be there at a very small level and the nose not detect them? Yes," Otwell said. "Is that level going to make someone sick? The answer is no, unless they were exposed to that particular level over a lifetime."

Hydrocarbons are especially aromatic. The smell of an auto repair shop, for example, leaves a powerful impression.

Some Smells Easier to Detect Than Others

Considering the fact that the nose is subjected to about 110,000 different smells, it's amazing that humans can tell the difference between gasoline and perfume. Some smells are easier to detect than others, sometimes because of how we first encountered them.

Researchers at Northwestern University found that a smell associated with an unpleasant event became very easy to recognize later. That would suggest that smells associated with one of the worst oil spills in history will linger on.