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Still, AquaBounty, the company that raises the salmon, has big plans to expand. So, here are some quick answers to questions you might have about the futuristic fish.

What are the health and environmental concerns?

AquAdvantage Salmon is Atlantic salmon modified with DNA from Chinook salmon and the cold-tolerant ocean pout. AquAdvantage fish grow twice as fast as their non-GMO cousins in their early stages, which means they require less feed. The amount of feed that farmed fish consume has long been one of the biggest criticisms lobbed at the aquaculture industry, and AquaBounty markets the innovation as an environmental win. According to the U.S. Food and Drug Administration (FDA), the agency completed a “comprehensive analysis of the scientific evidence” and concluded that raising the salmon at approved farms would have no significant environmental impacts and that the fish are safe to eat.

But a coalition of organizations that includes CFS say the FDA’s assessment was insufficient; in a 2020 ruling, a California court agreed with them. Hanson says the main environmental concern is what might happen if the GMO fish escaped and bred with wild Atlantic salmon. In Norway, for example, genetic pollution from farmed fish has devastated wild salmon populations.

Currently, the FDA has only approved production of sterile GMO salmon in closed, land-based systems, minimizing that possibility. But Hanson said AquaBounty’s egg production facility is close to the shore on Prince Edward Island, so the risk of escape due to extreme weather events is still present. He also speculated that employees at the farms could take the eggs to raise fish in local waterways, and that the company may try to get ocean-based GMO salmon farms approved in the future: This April, Maine’s Department of Marine Resources rejected the company’s permit application for an offshore salmon farm due to concerns that it would use genetically modified eggs.

In an email, AquaBounty President and CEO Sylvia Wulf told Civil Eats the GMO salmon “will not be raised in ocean-based pens” and that the company’s land-based systems utilize multiple containment strategies so that “the risk of AquaBounty’s fish to the environment remains, and will continue to remain, low.”

In terms of health, Hanson and other advocates say that the research FDA reviewed to determine safety was far from adequate. The study that found no conclusive risks related to allergenicity included just six salmon in each research group. And the two small studies that evaluated whether the fish contain elevated levels of concerning growth hormones were based on what Michael Hansen, a senior scientist at Consumer Reports, calls “sloppy science and deficient data.” In one, for example, hormones were measured in fish that were just two ounces, not when they had reached the much larger size at which they’re sold.

Finally, many people eat salmon as a source of healthy omega-3 fatty acids. While farmed salmon including AquAdvantage salmon are a good source of those fats, because of their diets, farmed salmon tend to contain higher amounts of less-healthy omega-6s, tipping the ratio of omega-3s to omega-6s in the wrong direction. Hansen said the research so far suggests that AquaBounty’s genetic engineering alters that ratio even further.

Where is it sold?

More than 80 U.S. companies with a combined 18,000 locations have said they will not carry the fish. On that list are major institutional food service companies Aramark, Compass, and Sodexo; they’re joined by nearly every major grocery chain, including Walmart, Costco, Kroger, Giant Eagle Whole Foods, and Trader Joe’s. “We’re seeing no sales at grocery stores,” Hansen said.

Last May, AquaBounty announced one restaurant distributor, the Philadelphia-based Samuels and Son Seafood, which sells to restaurants in Pennsylvania, New Jersey, and Delaware. However, Wulf said Samuels and Son then “decided to wait until our product was successfully introduced in the marketplace” and has not distributed the salmon. “AquaBounty is currently selling all of its weekly harvests to a variety of customers which we won’t name for proprietary considerations,” she said.

Will you know it’s GMO?

In 2015,we reported that GMO salmon would likely be indistinguishable in the marketplace. Then, in 2016, Congress passed a law mandating GMO labeling. However, critics say the final rules are confusing to consumers, and they include exceptions. As of January 1, 2022, if it’s sold in the grocery store, AquAdvantage Salmon will have to include a seal that says “bioengineered” or the product could also include a link or QR code pointing to that information. Restaurants, where the salmon is likely currently sold, are exempt from disclosure.

Will more GMO salmon be sold soon?

Right now, AquAdvantage is the only company in the game and its product is only approved for consumption in the U.S., Canada, and Brazil. But AquaBounty is moving forward on a new production facility in Pioneer, Ohio, that its executives say will produce 10,000 tons of salmon per year—more than eight times the output of the current Indiana facility. The European Union is also doing its own studies on GMO salmon, Hansen said, and Argentina has approved the company’s genetically engineered tilapia.

In the meantime, the legal battles will continue. After the 2020 ruling that the FDA “failed to sufficiently consider whether AquAdvantage salmon may affect endangered wild salmon,” the court sent the approval back to the agency to more fully consider. However, sales were not halted in the meantime, and CFS recently filed another lawsuit to compel the FDA to release documents related to the approval.

This article has been updated to correct the production quantities of AquAdvantage’s Ohio facility.