Seafood-rich diets may come with a plethora of 'permanent chemicals': study

(the hill) — People who frequently consume seafood may be at increased risk of exposure to toxic “permanent chemicals,” a study finds.

Of all the fish species tested, fresh from coastal New Hampshire markets, shrimp contained the most alarming levels of these PFAS compounds, according to research released Friday. And it was lobster. exposure and health.

PFAS (per- and polyfluoroalkyl substances) are released into the environment from a variety of sources, including industrial waste, certain types of firefighting foam, and common household products.

These synthetic compounds have been linked to several different types of cancer and are contaminating the nation's water resources and the species that live there.

Scientists have long evaluated the presence of PFAS in freshwater fish, but the study authors noted that seafood has so far received less scrutiny.

“Most existing research has focused on PFAS levels in freshwater species that are not primarily consumed by humans,” said corresponding author Megan Romano, associate professor of epidemiology at Dartmouth College's Geisel School of Medicine. in a statement.

To draw their conclusions, the authors combined analysis of PFAS concentrations in fresh seafood with results from a statewide survey of New Hampshire dietary habits. The authors noted that national studies show that New England as a region is the largest consumer of seafood.

Scientists measured levels of 26 PFAS (several thousand of them) in samples of the most consumed marine species in the region, including cod, haddock, lobster, salmon, scallops, shrimp and tuna. did.

They bought fresh product from markets along the New Hampshire coast, but the seafood came from a variety of regions, according to the study.

The researchers found that local market shrimp and lobster consistently had the highest PFAS concentrations, while other types of seafood generally had lower PFAS concentrations.

The scientists then calculated exposure to three specific PFAS offenders (PFOS, PFNA, and PFUnDA) using the ratio of a compound's daily intake to its respective federal or state safe consumption threshold. assessed the risks.

The authors then combed through the results of the Granite State Panel, in which 1,829 New Hampshire residents took part in an online survey about their seafood consumption. Shrimp, haddock and salmon were the most popular and regular menu items.

Ultimately, the researchers found that among people who frequently consumed seafood, the levels of PFUnDA and PFNA in shrimp did not pose a risk, but the levels of PFOS did.

The study found that while PFUnDA concentrations in lobsters are a potential concern for people consuming large amounts, PFOS and PFNA levels do not pose such a risk.

However, the authors noted that while New Hampshire residents do tend to eat more seafood, they do not do so uniformly.

More than half of those who reported consuming seafood in the week before the survey lived along the coast or near the Massachusetts border.

Opinions are also divided by economic status, with more than 60% of households earning less than $45,000 a year reporting eating seafood at least once a week, compared to 60% of households earning less than $45,000 a year. The survey found that this was less common in households.

“Our recommendation is not to avoid eating seafood; seafood is a good source of lean protein and omega fatty acids,” Romano said. “But it is also a potentially underappreciated source of PFAS exposure in humans.”

“Understanding this risk-benefit trade-off for seafood consumption is important for people making dietary decisions, especially vulnerable populations such as pregnant people and children,” she added. .