Toxic chemicals released by Hawai'i industries dropped for the third straight year in 2006 — falling 2.8 percent from the previous year, the U.S. Environmental Protection Agency announced yesterday.

The 38 facilities released a total of 3 million pounds of toxic chemicals, a reduction of 87,000 pounds.

Overall, Hawai'i ranked 49th out of 56 states, U.S. territories and the District of Columbia in total emissions. The American Lung Association also listed Honolulu as the third cleanest city in the country for long-term air pollution in 2006.

"We are pleased to report a decrease in the amount of toxic chemicals released in Hawai'i in 2006," said Wayne Nastri, EPA administrator for the Pacific Southwest region.

Hawaiian Electric Co. and its subsidiaries — Hawai'i Electric Light Co. and Maui Electric Co. Ltd. — were among five of the top 10 companies or facilities that had the highest levels of toxic releases, according to the EPA.

"We are the largest industrial source because there isn't any large-scale manufacturing in Hawai'i," HECO spokesman Darren Pai said. "So as a result, it's natural to see electrical generating stations on this list year after year."

People can further help decrease toxic emissions by using less energy, Pai said.

The Tesoro Hawaii refinery in Kapolei came in ninth on the list with a release of 97,480 pounds and has made the top 10 list before.

"There wasn't any unusual incident in 2006," Tesoro spokes-man Nathan Hokama said. "The cumulative total is really reflective of the refining and distribution process. We have tank farms at the refinery and when we lower the covers, some emissions come out. When they fuel the barges, some emissions come out. It all adds to the total."

Schofield Barracks and Wheeler Army Airfield were 10th on the list, with releases of 74,850 pounds. A statement from Army said, "The yearly numbers for Schofield ranges tend to fluctuate based on range activity; deployments figure in quite heavily.

"Any time soldiers are deployed, the amount of training ... decreases (although other services do use Army ranges for training). Likewise, after the soldiers return, they begin to reset and train for possible future deployments, so the training on ranges increases."

The Army has invested $58 million over the past 5 years establishing environmental and cultural programs for installations and training areas in Hawai'i, it said. Plans are to spend $135 million more over the next seven years to continue and expand these programs, it said.

Jeff Mikulina, director of the Sierra Club Hawai'i Chapter, welcomed the three-year trend of reductions but cautioned "not to go patting ourselves on the back."

"The big 10 contributors to the release of toxins haven't changed," Mikulina said. "No. 1 — the Kahe power plant — remains the largest single emitter of greenhouse gases. It helps to highlight that the more we reduce greenhouse gas emissions, the more we're going to be reducing our toxic emissions as well, especially with the refineries. The more we ratchet down fossil fuel use, the more we'll reduce our toxic emissions."