Salmon advisory issued by state

NASHUA – New concern about the buildup of toxins in adult, hatchery-raised salmon has led the state to recommend that adult fishermen limit their consumption of brood stock released from the federal hatchery in Nashua, and that people under 15 shouldn’t eat them at all.

Further, it will be tough to find many of these fish to eat this spring: Delays caused by testing means that very few of the fish will be stocked in the Merrimack and Pemigewasset rivers until the fall.

“We’re stocking just a small number of brood-stock Atlantic salmon, just a few hundred, next week. The remainder, about 1,400 (fish) . . . at the moment, our goal is to have them cared for over the summer and released in the fall,” said Liza Poinier, information officer for the state Fish and Game Department.

Normally, about 750 are stocked in the spring for recreational fishermen, and 750 in the fall. But river waters are now too warm, said Poinier; if the salmon were stocked, they would return to the sea so quickly that nobody could catch them.

The matter came up in response to an article in the Jan. 9 issue of the journal Science that said PCBs and dioxins were present in farm-raised salmon that were fed the same diet as the salmon in Nashua.

The state Department of Health and Human Services was awaiting results from testing before recommending whether the fish raised in Nashua could be released into state rivers.

The state announced Friday that the brood-stock Atlantic salmon are safe for limited consumption by people aged 16 and older – just one-half of a meal, or 4 ounces, per month. Younger people should not eat the fish at all, the state said.

Previously, the brood-stock salmon were covered by the same general consumption limits recommended for all freshwater fish in New Hampshire: No more than four, 8-ounce meals per month, with pregnant or nursing women and children under age 7 limited to one meal per month.

Those limits were imposed because of concern about the buildup of heavy metals, notably mercury. The new limits concern an entirely different set of toxins, particularly PCBs.

The federal hatchery in Nashua stocks the salmon as part of the 11-year-old Merrimack River Anadromous Fish Restoration Program, which is working to restore migratory fish populations to New England.

These fish are kept to produce offspring, or “fry,” more than a million of which are released around New England each spring.

These fry are not affected by the new limits because they have not been fed the same fishmeal for the same length of time as the brood stock.

The study in Science found that the fishmeal fed to farmed salmon is often contaminated with PCBs, and that farmed salmon generally contain more fat than wild salmon. PCBs are stored in fat and remain there for an extended period of time.

David Brooks can be reached at 594-5831 or