WASHINGTON – Tinker with the genetics of salmon and maybe you create a revolutionary new food source that could help the environment and feed the hungry.

Or maybe you're creating what some say is an untested "frankenfish" that could cause unknown allergic reactions and the eventual decimation of the wild salmon population.

The Food and Drug Administration hears both arguments Monday when it begins a two-day meeting on whether to approve the marketing of the genetically engineered fish, which would be the first such animal approved for human consumption. The agency has already said the salmon, which grows twice as fast as conventional salmon, is as safe to eat as the traditional variety.

Approval of the salmon would open the door for a variety of other genetically engineered animals, including an environmentally friendly pig that is being developed in Canada or cattle that are resistant to mad cow disease.

"For future applications out there the sky's the limit," said David Edwards of the Biotechnology Industry Association. "If you can imagine it, scientists can try to do it."

AquaBounty submitted its first application for FDA approval in 1995, but the agency decided not until two years ago to consider applications for genetically engineered animals — a move seen as a breakthrough by the biotechnology industry.

Genetic engineering is already widely used for crops, but the government until now has not considered allowing the consumption of modified animals. Although the potential benefits — and profits — are huge, many individuals have qualms about manipulating the genetic code of other living creatures.

Genetically engineered — or GE — animals are not clones, which the FDA has already said are safe to eat. Clones are copies of an animal. With GE animals, their DNA has been altered to produce a desirable characteristic.

In the case of the salmon, AquaBounty has added a growth hormone from a Chinook salmon that allows the fish to produce their growth hormone all year long. The engineers were able to keep the hormone active by using another gene from an eel-like fish called an ocean pout that acts like an on switch for the hormone, according to the company. Conventional salmon only produce the growth hormone some of the time.

In documents released ahead of the hearing, the FDA said there were no biologically relevant differences between the engineered salmon and conventional salmon, and there is a reasonable certainty of no harm from its consumption.

Critics have two main concerns: The safety of the food to humans and the salmon's effect on the environment.

Because the altered fish has never been eaten before, they say, it could include dangerous allergens, especially because seafood is highly allergenic. They also worry that the fish will escape and intermingle with the wild salmon population, which is already endangered.They would grow fast and consume more food to the detriment of the conventional wild salmon, the critics fear.

A wide range of environmental, food safety and consumer groups have argued that more public studies are needed and the current FDA process is inadequate because it allows the company to keep some proprietary information private. Modified foods are regulated under the same process used for animal drugs.

"It is outrageous to keep this vital information secret," said Wenonah Hauter, director of the advocacy group Food & Water Watch. "Consumers have a right to know what FDA is trying to allow into our food supply."

Dr. Michael Hansen, senior scientist at Consumers Union, the publisher of Consumer Reports, says the agency is relying on too little data, much of which is supplied by the company itself.

"FDA has set the bar very low," he said.

Ron Stotish, the chief executive of AquaBounty, countered that the company has more than addressed the concerns, and his product has come under much more scrutiny than most food.

"This is perhaps the most studied fish in history," he said. "Environmentally this is a very sustainable technology."

The company has several safeguards in place to allay concerns. All the fish would be bred female and sterile, though a small percentage may be able to breed. They would be bred in confined pools where the potential for escape would be very low.

In its environmental analysis of the fish released earlier this month, the FDA agreed with the company that there are enough safeguards in place.

Stotish says the fish would be bred in better conditions than many of the world's farmed salmon, and could be located closer to population centers to help feed more people. The company has also said the increase in engineered salmon production could help relieve endangered wild salmon populations.

The company is also arguing that the fish do not need to be labeled as genetically engineered, so the common customer would not know if they were eating the modified product or the conventional product. The second day of the FDA meeting will focus on the labeling question.

"This fish is identical to the traditional food," maintained Stotish. "The label could even be misleading because it implies a difference that doesn't exist."

At the meeting Monday, the FDA, the company and critics will present their findings to an advisory committee, which will in turn advise the FDA. A decision will come after the meeting, though it is unclear how long that will take. If approved, the fish could be in grocery stores in two years, the company estimates.

The industry says their job will be to counter the common impression that the modified salmon are "frankenfish."

"In the story of Frankenstein it was the fear of the people driving it, it wasn't the monster that was evil," says Edwards of the Biotechnology Industry Association. "If you look at the science and the safety and you look at the benefits, they become very exciting products."