Fish consumption guidelines add three Northland waterbodies to “do not eat” list

The Minnesota Department of Health (MDH) has new fish consumption guidance updates to reflect per- and polyfluoroalkyl substances (PFAS) found in fish in some waterbodies. The updated guidelines focus on PFAS data but also include protection against mercury and polychlorinated biphenyls (PCBs).

A positive change is for those who fish in Lake Superior. MDH has determined that rainbow smelt can be eaten more frequently, up to one serving per week. The previous guideline was to consume no more than one serving per month. Research Scientist Angela Preimesberger works with MDH’s Fish Consumption Guidance Program and says the department works closely with the Minnesota Pollution Control Agency (MPCA).

“[MPCA] completed a large study of fish and the impacts of PFAS in the Lake Superior Basin,” explained Preimesberger. “They were able to collect a very large data set on rainbow smelt and the original one that led to an advisory in 2021 to limit servings to one a month. That was preliminary data, and this newer study gave us a really great look at the PFAS information that’s available, and we could improve the guidelines.”

Other areas have updated guidelines that decrease the recommended consumption. This includes some waterbodies in St. Louis County that have been on the list of guidelines for years.

“There is a location near the Duluth International Airport where PFAS products had been used and contaminated the groundwater and some surface water systems, particularly Miller Creek,” said Preimesberger. “That area has been on the Minnesota Pollution Control Agency’s list of PFAS sites for study and evaluation, and so there had been some limits on some trout in Miller Creek in the past and a few species in Fish Lake Flowage and Wild Rice Lake.”

Fish Lake Flowage, Wild Rice Lake, and Miller Creek, as well as Beaver River, used to have a few species with consumption guidelines that were less frequent than the Statewide Fish Consumption Guidelines. It is now recommended that those in sensitive groups do not eat fish from these lakes. This is due to a combination of having more data from MPCA and a lower threshold from MDH.

“These PFAS contaminants can affect developmental effects from low birth weight to reduced immune effects in children, and they can also lead to liver damage and can increase risk for some cancers in adults,” explained Preimesberger. “This newer data provides a better understanding of the toxicity of these chemicals. It was prudent to lower the guidelines and recommend that sensitive populations not eat fish from these waters.”

Preimesberger added that sensitive groups include people who are or may become pregnant, people who are breastfeeding or may breastfeed, and children under the age of 15. Those not in a sensitive group can eat up to one serving of fish in the contaminated areas a month, sticking with one species.

The full list of updated fish consumption guidelines can be found at this link. The MDH would also like the public to know that PFAS exposure is not limited to fish consumption. More information on avoiding PFAS exposure in the home can be found on the MDH website.