Warning not to eat Westerschelde seafood due to PFAS chemicals

Various types of fish, crustaceans, and shellfish from the Westerschelde contain such high concentrations of PFAS chemicals that the National Institute for Public Health and Environment (RIVM) issued a warning to eat them "as little as possible." The institute calculated how much people could eat of various species without ingesting excessive amounts of harmful chemicals. For example, people should eat a portion of flounder no more than twice a year to avoid exceeding limit values.

On average, Netherlands residents ingest too high concentrations of PFAS through their food and drinking water, the RIVM said in a report last year. Therefore, it is "important to further increase the intake of PFAS as little as possible," the researchers said on Wednesday.

PFAS are human-made and barely biodegradable. The substances are present in many places due to widespread use and discharges. Excessive exposure to PFAS could damage your health. Certain types of PFAS can impair young children's immune systems. Exposure above a certain level also increases the risk of cancer, liver damage, and high cholesterol. The Westerschelde contains a lot of PFAS because chemical group 3M in Zwijndrecht, Belgium, discharged into the Scheldt for years.

The RIVM aimed its warning specifically on hobby fishers because they mainly catch fish in the area. "Since it is plausible that people who get these products from the Westerschelde are enthusiasts, it is assumed that they will consume large portions," the researchers said. There is hardly any commercial fishing in the polluted Westerschelde. Shrimp fishers who were active there recently decided to avoid the estuary as a precaution.

According to the study, people who ingest no other products containing PFAS could eat sea bass from the Westerschelde one to six times a year. The range is so large because the quantities involved are minimal, which entails statistical uncertainty. A portion of shrimp more than five to six times a year could lead to overexposure. The margin is larger for oysters and mussels: no more than twice a week in the best-case scenario and a maximum of event times a year in the worst case. Professional mussel fishers are not active in the area. The vegetable sea lavender does not contain too high PFAS levels.

The RIVM recently published a first study into swimming in the Westerschelde. The outcome was quite reassuring. PFAS concentrations measured at a site believed to be more polluted than the official swimming sites were not too high. Further investigation will follow at three swimming locations.