Fish caught in the city's drinking water supply are not fit for human consumption, according to a warning from the Massachusetts Department of Public Health.
Area lakes, ponds and waterways are contaminated by mercury, which is toxic to the human nervous system, according to a report released by watchdog agency Environment Massachusetts.
The state Health Department's warning for Haverhill bodies of water range in severity from limiting consumption of certain fish to prohibiting the consumption of any fish caught.
Chadwick Pond, Lake Pentucket and Kenoza Lake, which supplies the city's drinking water, received the strongest warning: P6 — "The general public should not consume any fish from this water body."
Crystal Lake received three lesser warnings. P1, which says children younger than 12, pregnant women, women of child bearing age and nursing women should avoid eating fish from this body of water; P2, meaning the general public should avoid eating largemouth bass; and P4, meaning the public should limit their consumption of nonaffected fish to two meals per month.
The Millvale Reservoir received P1 and P2 warnings, while Lake Saltonstall, or Plug Pond, received P1, P2 and P3, which says that the general public should limit consumption of largemouth bass to two meals per month.
The greatest amount of mercury emissions comes from coal-fired power plants, Environment Massachusetts' report said. The toxin builds up in the fatty tissue of the fish. The water is safe to drink.
"Powering our nation's homes should not poison Massachusetts' waterways," said Audrey Richardson, clean energy associate for Environment Massachusetts. "Mercury pollution from power plans puts our environment and public health at risk, and we need the Environmental Protection Agency to force these facilities to clean up."
The Merrimack River carries warnings against eating any fish for children and women who are pregnant, nursing or of childbearing age. The public should eat no more than two meals per month of largemouth bass caught in the river. The Merrimack also carries restrictions for the white sucker fish.
Massachusetts is one of 16 states that regulates the mercury capture rate from power plant emissions, and has one of stingiest policies nationally. The state in 2008 set a requirement that 85 percent of mercury be captured before it is emitted into the environment. The 2012 goal is 95 percent.
The EPA is set to propose a nationwide standard to limit mercury pollution in March and finalize the proposal by November.
"What we're hoping is that the EPA cut mercury emissions by more than 90 percent across the country, which is just in line with Massachusetts' ruling," Richardson said.
Covanta Haverhill, an energy-from-waste power plant in the Ward Hill Business Park, produces its fuel from municipal solid waste, according to Ken Nydam, business manager for the plant.
"There is still some mercury out there, and to eliminate the concerns, we really need to eliminate household items that have mercury in them, like some toys, fluorescent lamps, thermometers and thermostats," he said, adding that Covanta sponsors Keep Mercury from Rising, an advertising campaign about the effect of mercury emissions. "Our goal is to educate the public."
He added that the awareness effort is particularly important because the public might not know how trash could eventually be converted into a mercury-emitting energy source.
"A lot of people don't realize that they may have products that have mercury," he said.
Covanta Haverhill has adapted a carbon-based technology to let the plant know when and if incoming waste has mercury in it. It's a defense that allows the plant to stay well above the state's 85 percent capture rate.
"If the mercury comes into the waste stream, we have a carbon-injection system that will capture it," he said, adding the carbon naturally reacts with mercury to show its presence. "We're usually the best performer in the state for our technology. We do actively want to keep it out, and we are well within the state limits. Almost negligible."
Even with the state's strong regulations limiting mercury emissions, Mark Balding, head of the fishing committee on Haverhill's Hound Rod and Gun Club, said he advocated a catch-and-release policy for last weekend's ice fishing derby, held on Chadwick Pond.
"Everything is catch and release," he said. "The fish in that pond are not deemed edible. It's just for the sport."
A nine-year ice fishing veteran, Balding added that he knows of few fisherman around the area who consume their respective catches.
"No one I know that fishes around the Merrimack Valley eats the fish they catch," he said.
The EPA has estimated that one in six women of childbearing age has enough mercury in her body, through a typical diet, to put an unborn child at risk, including learning and development disabilities and lower IQs. According to the EPA, this means that 689,000 of the 4.1 million babies born each year are exposed to dangerous mercury levels.
Joel Tickner, a professor of community health and sustainability at the University of Massachusetts Lowell, said the study shows the importance of researching and finding alternative energy sources.
"There is compelling evidence that mercury is a potent neurotoxicant and clear data documenting coal-fired power plants as a root source or mercury in our environment, our food and our bodies," he said. "We must urgently, yet carefully, effect a transition to safe, more sustainable forms of energy production that create jobs, fuel our nation's infrastructure and make us healthier and more sustainable."
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