The federal government’s latest list of the biggest polluters in Maine includes a handful of the state’s largest paper mills, including two in central Maine.

Collectively, 88 industrial sites in Maine produced 11.5 million pounds of pollutants in 2012, an increase of more than a half-million pounds over 2011, according to a toxic chemical report released by the Environmental Protection Agency on Monday.

While Maine’s emissions went up, the amount of emissions for the Northeast as a whole went down, by 2.55 percent, according to the report.

Nine of the 10 biggest polluters on the list were associated with the state’s pulp and paper industry. The top polluter on the list was Rumford Paper Co., which released more than 3 million pounds of toxic chemicals into the environment in 2012. The second on the list, with more than 2.2 million pounds of emissions, was McCain Foods, a potato processing company that operates a plant in Easton.

In central Maine, S.D. Warren Co., of Skowhegan, which does business as Sappi Fine Paper, was third on the list, with more than 2 million pounds of toxic chemicals emitted. In 2011, the company was ranked fourth. The company’s Westbrook operation also made the list as the state’s eighth-largest polluter, with about 257,000 pounds of emissions.

Verso Paper Holdings, of Jay, was the fourth-largest polluter in the state, with about 1.6 million pounds of toxic emissions. In 2011, the company was ranked third. Verso’s Bucksport mill also made the list, in tenth place, with about 139,000 pounds of toxic emissions.

State environmental leaders said they are concerned about the increase and urged tougher restrictions on polluters, while industry leaders said the increase is likely a sign that the amount of paper produced increased in 2012, as the state continues to rebound from a national economic recession.

“We are disturbed that the amount of toxic chemicals released into Maine’s air, waters and land has increased, particularly at a time when industrial facilities in other New England states managed to decrease their toxic pollution,” said Judy Berk, spokeswoman of the Natural Resources Council of Maine, shortly after the report was released Monday. “While we have not had time to review the new data in depth, we do know that toxic pollution may seriously harm to the health of Maine people and wildlife. We urge the EPA, DEP and Maine businesses to do better, and go all out to reduce the use and release of toxic chemicals throughout Maine and the nation.”

John Williams, president of the Maine Pulp and Paper Association, said the industry produces the highest number of toxic emissions because it is the biggest manufacturing industry.

“I would believe that the emissions are a little bit higher because as we’re coming out of the recession the mills have been producing a lot of pulp and paper,” he said. “There really haven’t been any significant changes in the practices in the mills.”

Williams said the overall trend in the industry has been toward cleaner discharges, with environmental laws leading to investments in technologies that clean air and water emissions of pollution as they leave the paper mills.

“Our mills have invested hundreds of millions of dollars in pollution control equipment,” he said. “The days of our heavily polluting mills are long behind us.”

He said Maine’s environmental laws are among the toughest in the country.

In response to the release, Sappi spokeswoman Joanna Rieke said in a prepared statement that the company is in compliance with all municipal, state and federal rules.

“The law requires reporting on these substances even if they are not particularly hazardous in the form they are released,” she said. “And even if they are present at very low levels, including materials that are sent to our onsite secure landfill.”

Rieke drew a connection between Sappi’s inclusion on the list and its position as one of the largest manufacturing facilities in the state.

“Sappi Fine Paper North America is committed to managing our environmental impact in the communities in which we operate, and is dedicated to implementing internationally recognized environmental management systems,” she said.

Verso did not return calls seeking comment on Monday afternoon.

Every other company on the list — Woodland Pulp Co., of Baileyville, Red Shield Acquisition, of Old Town; Great Northern Paper, of East Millinocket; and Lincoln Paper & Tissue, of Lincoln — is associated with the pulp and paper industry.

The EPA report also listed the top 10 toxic substances being emitted in the state, by weight.

The most emitted toxin in the report were zinc compounds, with more than 3 million pounds in 2012, followed by nitrate compounds, with 2.5 million pounds, and methanol, with about 2 million pounds. The other toxic chemicals that made the list are manganese compounds, ammonia, hydrochloric acid, aceteldehyde, barium compounds and chromium compounds, which were number 10 on the list with 94,000 pounds emitted.

New on the list of pollutants this year was hydrogen sulfide, which debuted at No. 6, with about 588,000 pounds released in 2012. This is the first year the EPA has tracked the notoriously odorous chemical, which is used to help break down wood into pulp.

Williams said those who live in mill towns know there is less hydrogen sulfide being produced than in previous decades because they can smell the difference.

“In Maine, the mill towns occasionally get that hydrogen sulfide smell, but not very much anymore,” he said.

The Toxic Release Inventory, which has been released every year since 1986, includes information on chemicals that are released into the environment from the mills, as well as chemicals transported to disposal facilities. The EPA noted in its report that changes in volume could be attributable to factors including changes in the business cycle that don’t reflect a company’s pollution prevention program.

Curt Spaulding, regional administrator of the EPA’s New England office, said in a statement released with the report that the data helps people protect their health and gives communities information to help guide their decisions.

Matt Hongoltz-Hetling — 861-9287 mhhetling@centralmaine.com Twitter: @hh_matt