SAN FRANCISCO (KCBS) — As the Food and Drug administration is expected to approve the sale of genetically-modified salmon, Trader Joe’s and Whole Foods Market said they won’t sell the fish.

The refusal by the two stores sat well with many of the customers at the Trader Joe’s at Hyde and California streets in San Francisco. Some expressed a desire to keep genetically modified food items separate from what they consider real food, adding that they were uneasy about not knowing what’s in genetically modified foods.

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Salmon producer AquaBounty said their salmon is safe and doesn’t look any different than wild, Atlantic or Pacific varieties. The genetically reformulated fish is designed to grow twice as fast, which they said doesn’t bother some shoppers.

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Critics of the fish said that there could be side effects attached to the modified fish from the technology involved.

Whole Foods issued a statement to KCBS in which they said their quality standards prohibit the use or sale of genetically modified or cloned seafood.

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