Philly Snapper soup comes with a side of zinc and lead, researchers find

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Turtle soup at Philadelphia’s Oyster House. (Kimberly Paynter/WHYY)

Turtle soup at Philadelphia’s Oyster House. (Kimberly Paynter/WHYY)

Oyster House owner Sam Mink can’t remember the first time he tried snapper soup.

He grew up eating it when his father owned the restaurant at 15th and Sansom streets. Today, it’s still on the menu, just as it was 43 years ago when it opened.

Mink said the soup has a unique flavor. Seasoned with clove and allspice, it’s a rich and hearty soup with vegetables and a lot of turtle meat and finished tableside with sherry.

Sam Mink is the owner of the Oyster House in Center City, Philadelphia. (Kimberly Paynter/WHYY)

“I love putting the sherry into it,” Mink said. “Like to me, the cocktail sherry at the end makes the soup. It’s so good.”

Mink said the soup is a Philadelphia tradition and staple at his restaurant, but it’s not offered on many menus in the city anymore. He said some of his customers come to Oyster House just for snapper soup.

The Oyster House in Philadelphia. (Kimberly Paynter/WHYY)

But this tradition is facing a very modern problem: environmental pollution.

When Arcadia University researcher Tobias Landberg saw snapper soup on the menu at a local pub, he became concerned that eating the soup might be a health risk. The problem, he says, is that snapping turtles are tough creatures.

“They are getting food sources from all sorts of different places, and they’re really long-lived animals and they’re especially hardy, which means that they can tolerate extremely polluted environments without showing too many ill effects,” Landberg said. “It’s their resilience that really makes them a potential carrier of really excessively high loads of heavy metal contaminants.”

Landberg suspected that these contaminants were making their way into snapper soup. His team focused on 20 restaurants in and around Philadelphia that serve it. They ordered cups of soup to go, then brought them back to the lab for testing.

His team tested the turtle meat in each order for zinc, mercury and lead, common pollutants that can remain in the soil and waterways long after the source of the pollution is gone. They found all three heavy metals in soup samples.

At least half the samples had zinc levels 10 times greater than what the CDC recommends. That much zinc could cause stomach cramps or nausea, and possibly organ damage.

Landberg said that since zinc is an essential nutrient, this isn’t as troubling as their other results.

“We’re sort of more concerned about the lead and mercury, for which there are no known safe levels of consumption,” he said. “And when more than half of the samples are coming back with measurable levels of these toxins and pollutants, these heavy metals, then we start to really worry about the long-term effects of consuming this for customers, and we worry about the restaurants and chefs, that they might be harming their customers.”

The FDA said that mercury is in most, if not all fish, at least in small amounts. Mercury is the biggest concern for pregnant women and children, but it can be harmful to anyone at high levels. However, because seafood provides health benefits, the FDA still recommends eating some of it.

According to these guidelines, the turtle soups might be safe to eat at least once a week for healthy adults, depending on how much meat was in the soup.

Chef Aaron Gottesman holds a bowl of turtle soup at Philadelphia’s Oyster House. (Kimberly Paynter/WHYY)

FDA spokesperson Peter Cassell would not directly comment on this study. He said the FDA doesn’t publish consumption guidelines for turtles because the agency doesn’t recommend eating them.

Oyster House owner Sam Mink isn’t worried about heavy metals in his soup or the researchers’ recent results. He said the turtles for his soup come from pristine areas, although he doesn’t actually track exactly where his suppliers catch them.

He said moderation — as with many things — is important.

“You shouldn’t eat shrimp every day,” he said. “You shouldn’t eat a hot dog every day either, you know? I don’t see snapping turtle meat as being a high level of concern for a lot of people because it’s not consumed by many people. And I think a little bit … now and again… having some soup… I don’t see that being a major issue. You walk outside, you breathe toxins just by walking across the street. We have to live.”

Arcadia researcher Landberg stresses that this is not a problem with any one restaurant. It’s a general issue with turtle soup. And while there are no “safe” levels of consumption for heavy metals, he doesn’t expect many people to eat turtle soup so often they endanger themselves.

He just wants restaurant customers to know what they’re getting in their next bowl.

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