State environmental officials are warning people about the amount of fish they eat that were caught from Squam Lake because of elevated levels of chemicals detected in tissue samples.

The advisory comes as high levels of polychlorinated biphenyls (PCBs), were detected in fish tissue samples, according to the New Hampshire Department of Environmental Services (NHDES). PCBs are man-made chemicals used as coolants and lubricants that are considered a probable human carcinogen, according to the March 30 advisory.

The more restrictive fish consumption limits, for all fish caught in Squam Lake, came after NHDES followed up on previous research conducted by the Loon Preservation Committee and the Squam Lake Association that identified the elevated contaminant levels in loon eggs and lake sediment, according to a news release.

“In this study, NHDES biology staff collected smallmouth bass and yellow perch samples in an effort to better understand the potential risks to human health associated with eating fish caught in the lake,” the news release reads.

The samples were also analyzed for Polyfluoroalkyl substances (PFAS) and mercury concentrations, but only PCB data is available at this time.

NHDES evaluated the range of PCB concentrations in fish tissue for potential human health risks, specifically the cancer risk.

“Based on this evaluation, NHDES has concluded that the PCB concentrations in fish are high enough to present risks from exposure and their consumption should be limited,” the news release reads.

The advisory for Squam Lake is now more restrictive than the statewide mercury consumption guidelines.

New Recommended Consumption Limits Based on Total PCB concentration for Squam Lake

SOURCE: New Hampshire Department of Environmental Services 

Fish Adults and children >7 years of age (8 oz. meal) Women of childbearing age (8 oz. meal) Children <7 years of age (4 oz. meal)
Smallmouth bass and other fish 1 meal every 4 months (3 meals per year) 1 meal every 6 months (2 meals per year) 1 meal every year
Yellow perch 1 meal every month (12 meals per year) 1 meal every 2 months (6 meals per year) 1 meal every 3 months (4 meals per year)

The new guidelines recommend that adults and children over age 7 only eat one 8-ounce meal every four months (three meals per year) for smallmouth bass and other fish. There are other restrictions for women of childbearing age and children.

The department said there’s no known risk to catching and handling of fish in Squam Lake, “so catch and release fishing is not impacted,” the news release reads

For the full advisory and restrictions, go to